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Cast Stone and Precast Concrete textures and products manufactured by Ventura Precast.

Glossary of textures
 

Description: Scagliola Texture    (click to enlarge)  

bulletScagliola texture, made in precast concrete or GFRC product, rich natural stone texture resembling cut marble.
bulletName is derived from the Italian word "scaglia" meaning "chips of stone".
bulletAncient secret formula dating from the 15th century, revived and improved upon by Italian monks in the 17th century, and which had all but disappeared by the 19th century. 
bulletLightweight thin wall GFRC or full weight precast, with smooth polished surface with many small irregular fissures and swirls.
bulletMade from crushed limestone or aggregates, fiberglass reinforcement, cement, and integrated pigment.
bulletHand laid into molds.       

 

Description: Travertine Texture   Precast concrete Travertine texture chip  (click to enlarge)  

bulletTravertine texture, made in precast concrete or GFRC product, resembles travertine or cut and polished limestone.
bulletLightweight thin wall GFRC or full weight precast, with smooth regular polished surface with small irregular fissures.
bulletMade from sand or aggregates, fiberglass reinforcement, cement, and integrated pigment.
bulletHand laid into molds.       

 

Description: Old World Texture  Precast Concrete "Old World" texture  (click to enlarge)  

bulletOld world texture, precast concrete or GFRC product, resembles aged stone with flashes of color and deep fissures.
bulletLightweight thin wall GFRC or full weight precast, with bright multicolored hand made highlights.
bulletMade from sand or special aggregates, fiberglass reinforcement, cement, and integrated pigment.
bulletHand laid into molds.
     

Description: Sanded Texture   (click to enlarge)  

bulletSanded texture, precast concrete or GFRC product, resembles sandstone, regular smooth sandy surface.
bulletLightweight thin wall GFRC or full weight precast, with sandstone look and feel.
bulletMade from sand and aggregates, fiberglass reinforcement, cement, and integrated pigment.
bulletHand laid or sprayed into molds..       

 

Description: Smooth texture  (click to enlarge)  

bulletSmooth texture, precast concrete or GFRC product, smooth plaster like finish, with a regular surface.
bulletLightweight thin wall or full weight.
bulletMade from sand and aggregates, fiberglass reinforcement, cement, and integrated pigment.
bulletHand laid or sprayed into molds..       

 

 

Glossary of products


Description: GFRC  (glass fiber reinforced concrete)  Precast Concrete "Old World" texture  (click to enlarge)  

bulletGFRC  product, resembles aged stone at approximately 25% of the weight.
bulletLightweight thin wall with many different textures available (see above).
bulletMade from sand or aggregates, fiberglass reinforcement, cement, and integrated pigment.
bulletHand laid or machine sprayed into molds..       
 

 

Description: Precast Concrete         Precast concrete Travertine texture chip  (click to enlarge)   Precast concrete Sand texture chip   (click to enlarge)

bulletPrecast concrete can be made to resemble many natural products.
bulletPrecast concrete is "full weight" concrete with many different textures available (see above).
bulletMade from sand or aggregates, cement, and integrated pigment.
bulletWet poured or hand laid into molds.
 

 

Description: Cast Stone     Fino (fine) Texture chip  (click to enlarge)  

bulletCast stone resembles expensive cut limestone at 25% of the cost.
bulletCast stone is usually "full weight" concrete, with sharp edges and rich texture, more uniform in color and texture than other cast products.
bulletCan also be made in lightweight GFRC.
bulletMade from limestone sand, white cement and integrated pigment.
bulletDry packed into molds under extreme pressure.
bulletMore expensive than our other products.                
                                                                                  

 

Description: GRG (glass fiber reinforced gypsum)

bulletGRG can be made to resemble many natural products.
bulletRecommended for indoor use only (unless modified).
bulletMade from gypsum, sand or aggregates, polymers, and integrated pigment.
bulletWet poured, sprayed or hand applied into molds.

 

 

A short lesson on our concrete products.

 

GFRC  (glass fiber reinforced concrete)

We simulate aged stone by hand laying a mix of special aggregates and cement into molds with special "techniques", making the product look  time worn or aged, resembling the old stone moldings seen at many historical sites or buildings. The GFRC product is thinwall about 3/4" thick and is extremely strong and about 25% the weight of solid stone.
Precast concrete can also be sprayed into molds, resulting in a smooth unblemished surface.

 

Precast concrete

We also simulate limestone or sandstone by pouring a mix of wet concrete into molds and when cured are then sand washed, to remove the fine cured cement particles at the surface of the product, and hopefully expose the aggregates to give the product the highly desired limestone "look".
Precast concrete can also be sprayed into molds, resulting in a smooth unblemished surface.

 

Cast Stone

Cast stone, used by man since the Egyptian pyramids were constructed, is hand packed into molds under tremendous pressure, just as in nature when limestone is made from the extreme pressure on sand, lime and slurry over thousands of years. This technique of compacting sand, crushed limestone and colored pigment with a small amount of water ensures a product which closely resembles limestone. Uniform in color and texture because very little water is used in it's production, cast stone is used where limestone or sandstone is desired but is cost prohibitive. The surface of cast stone shows the aggregate naturally at its surface, simulating limestone or sandstone.
Cost's more than our other products because of the Materials used and the special molds needed in it's manufacture.


 

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Copyright © 2002  Ventura Cast Stone.
PO Box 552, Somis, CA 93066   (805) 386-8185 Fax: (805) 386-3002

 

 

 

Cast stone

We at Ventura Precast are pleased to introduce this lightweight GFRC cast stone or lightweight precast concrete if you will, into our line of precast concrete and cast stone. Because lightweight cast stone is made from fiberglass strand mixed with real limestone which gives it that stone look, it is suitable for fireplace mantle treatments.

Lightweight precast concrete
 Lightweight precast concrete is usually called GFRC or glass fiber reinforced concrete, and is manufactured by Ventura cast stone and installed in the Los Angeles, Ventura and Santa Barbara Counties. Precast concrete usually weights 100 lbs per cubic foot.  Gfrc usually weights 10 lbs per lin foot.  Precast concrete is a lower end product and does not simulate limestone as does cast stone. Precast concrete resembles finished concrete and the surface looks like your garage floor. Cast stone resembles limestone or sandstone. Lightweight GFRC precast concrete is not a new product but has been used for years, but not in architectural uses.

Our Cast Stone range of products are into two product types:

Dry Cast

The "Dry Cast" method is a two part process, a face material to give you the similar finish to natural stone. Mechanically compacted to the rear of this is the backing mix to give the units strength in the terms of handling ability

Dry cast units are immediately demoulded after casting and are hand finished to a very high standard.

Wet Cast

Wet Cast as the name suggests produces structural products like heads and sills but is also used for slabs, beams and other similar products, that are for high exposure or structural situations where greater loads are required on the finished unit. The Wet Cast also has the added advantage of specialist finishes with the use of special sand aggregates, a massive spectrum of colors can be achieved.

 

Introduction to Cast Stone (wet cast and dry cast)

Cast Stone is known by a variety of other names including art stone, reconstructed stone, reconstituted stone, artificial stone and manufactured stone. This defines cast stone as any material manufactured with aggregate and cementicious binder and intended to resemble in appearance, and be used in a similar way to, natural stone. Cast stone is either homogenous through out or consists of a facing material and backing concrete.

The method of production is split into two categories.

bulletSemidry mixes
bulletPrecast concrete or sometimes referred to as 'wet' cast.

Choice of manufacturing method

The majority of cast stone manufactures use the semi-dry method of production. And is the more commonly widely used method of manufacture. Early consultation with us is advisable to ascertain the correct method of production for your project.

Sizes: Components produced using the semidry method are limited in size with face dimensions of Ashlar units normally no greater than 1200x600mm. This is mainly because of the fact a semi dry mix is used, which require rapid and rigorous compaction with hand held pneumatic tampers. The semidry method of production is best suited to traditionally sized ashlars quoins, sills, copings, door and window surrounds, etc.

Structural requirements: Components requiring reinforcement which is more complex than a few straight bars or a layer of fabric reinforcement, must be produced using the wet cast method of production. This is because it is difficult to achieve thorough compaction of semidry mixes around congested reinforcement.

Appearance: Cast stone can replicate a variety of stone colors and finishes. The semidry method of production is used to simulate limestones and sandstones. Where a component has a particularly intricate pattern or profile including slender projections, precast concrete may have to be used in preference to the 'semidry' method. Good color matching between components can be achieved by both methods, although textural differences become apparent at close range.

Economics: Rapid production rates with frequent reuse of moulds are possible with cast stone produced using semidry mixes. Where as with the Wet Cast process a higher number of concrete molds is required to achieve the same casting program, but careful thought a planning stages of the contract can minimize the number of concrete molds. In Fact an additional 2-3 weeks extra lead-time for standard or semi standard products can sometimes be all that is needed to achieve the same casting program.

Comparison between the semidry and wet methods

The production of cast stone using semidry mixes differs from that of wet method in several ways.

Casting

Semi Dry ~ De-molding takes place immediately after compaction. This allows a rapid casting cycle with e.g. up to 100 or more basic components (sills, copings, etc.) a day from a single mould.

Wet Cast ~ Where as to manufacture the equivalent in wet cast it would not only take longer but you would require 1 mould per cast per day i.e. to produce 100 units a day you would need 100 moulds.

Semi Dry ~Compaction is carried out by pneumatic tampers rather than by vibration.

Wet Cast ~ Compaction is carried out by vibration.

Mixes

Semi Dry ~ *Separate facing and backing mixes are often used for components like ashlars, sills, heads and jambs, where the backing mix is concealed from view. Separate facing and backing mixes are used primarily to economize on the facing mix. BS1 217 requires a separate facing mix to be not less than 20 mm thick at any point, with semidry cement sand facing mixes and concrete backing mixes each mix is placed and compacted in immediate succession to ensure that they are effectively monolithic.

Wet Cast ~ Wet Cast units are manufactured from a through colored homogenous mix.

Semi Dry ~ Water repellent admixtures are invariably used in facing mixes to reduce permeability. Giving a water absorption of Grade B. All constituents are accurately weigh batched with the moisture content monitored regularly. Mix batches are necessarily small to prevent any premature drying of the mix. Thorough mixing and compaction are critical to ensure that the cast stone achieves the required density (typically between 1850-2100kg/m2), compressive strength and permeability.

Wet Cast ~ superplasticisers and accelerators are used to ensure good flow of the mix during vibration and compaction to achieve a smooth, compact and blow hole free finish (where ever possible finish smooth after dressing) also to give good early strength. Typical cube tests at 7-10 Days are that of the equivalent of that of a semi dry unit at 28 Days

Products are split into three categories.

Standard - Cast stone items that are manufactured in accordance with our Technical specification sheets. These items could be stock items or units, which are ready to cast at the first available production slot, with no moulds to produce. Products like standard head, sills or pier caps and copings. The cost of establishing the moulds is not same, thus for small production runs costs can be kept to the minimum. Also not forgetting lead times can be much shorter by not having to detail, obtain approval and then construct moulds.

Semi Standard - Cast stone items, which are similar to details within our Technical specification sheets. But say vary in length or require slight mould adaptation or modification.

Purpose Made - Cast Stone items which are manufactured in accordance with the contract documents. These units are made from new purpose made concrete molds. These would probably be specialized units, which are not contained in our brochure. We have our own in house design department, who will assist you in the process of your design advising you in Careful thought must be given in the planning process for purpose made products. Please consider the following.

bulletDesign and detailing of in house production drawings- Some times it is of necessity to produce working drawings of Architects details to enable production of moulds.

This process can some times take any thing from 2 10 days, dependant on how long it takes to get details approved.

 

bulletApproval of production drawings.

 

bulletProduction of Patterns- Sometimes it is necessary to produce units from G.R.P. or Rubber moulds.

 

bulletThis may involve the pattern being produced and before moulds are manufactured, approval of the pattern may be sort from the Architect or Client.

 

bulletApproval of production patterns

 

bulletManufacture of concrete molds

 

bulletProduction of Units

 

bulletCuring of units

 

bulletPackaging and Transportation to Site

 

Remember adequate time must be allowed for production of concrete molds.

Colors and Finishes

Natural stone colors are achieved either by reliance on the color of crushed rock and sands and aggregates or by the addition of pigments. White cement gray cement and a combination are often used. The use of pigments can give the cast stone greater scope in the selection of suitably graded aggregates, which permit good compaction and achieve a strong, dense mix. Iron oxides based pigments are normally used in small quantities (e.g. 0.2%-1% yellow iron oxide by weight of cement for yellow sandstone's and up to 5% red iron oxide for red sandstone). High proportions of pigment powder (above say 6 - 8% by weight of cement) are used sometimes to achieve unusual colors like blues and browns but generally these should be avoided.

A variety of traditional ashlar finishes can be replicated with cast stone, including plain, boasted, tooled, rockfaced, vermiculated. The other ashlar finishes are normally produced from latex:sand or concrete mold liners.

bulletSemi Dry ~ Plain finishes normally produced using sealed plywood mould liners or, where the shape, detail or longevity for mould dictates, fiberglass is used.
bulletWet Cast ~ unlike the semidry method, the wet cast mix produces a surface laitance which has to be removed after demoulding to reveal the color and texture of the fines layer. The laitance is removed by either acid etching or retarding the surface within the mould prior to curing and washing off after demolding to achieve a smaller large expose of aggregate.

Here is where specialist aggregates can be used to achieve some wonderful and varied finishes and colors.

Structural Use

Dependant on the situation all cast stone both Wet and Dry Cast can be used. But there are limitations in the Dry Cast process as opposed to Wet Cast: -

bulletSemi Dry ~ Components requiring reinforcement which is more complex than a few straight bars or a layer of fabric reinforcement are not possible. This is because it is difficult to achieve thorough compaction of semidry mixes using a pneumatic tamper in and around the congested reinforcement. Therefore Wet Cast is the option.
 
bulletWet Cast ~ unlike the semidry method, the Wet Cast mix is poured into the mould as thick liquid mix and compaction is achieved by vibration. So even the more complex arrangement of bars can be compacted sufficiently. The added advantage being the need to put any secondary support like pressed or fabricated steel lintel saving costs. Also we can manufacture structural beams for larger vehicle entranceways for example.

 

Cast Stone
 

Cast stone by Ventura Cast Stone installed in California city's such as Los Angeles, Beverly Hills, Bel Air, Ventura or Santa Barbara has to be mechanically fastened to the wood frame of a building usually with stainless steel or galvanized attachments, this because of earthquake codes.  There are many historical buildings in California with cast stone as part of their facade.  Cast stone in Los Angeles, Beverly hills, Bel Air, Ventura and Santa Barbara was at it's most popular in the 1900's.  In Santa Barbara, cast stone was used extensively in the downtown district and also in a primitive form at the Santa Barbara mission in the form of adobe, a mixture of mud and straw or horsehair mixed with water and hand shaped into molds.  Cast stone in the City of Ventura was used mainly on churches in the downtown area.  Cast stone in Los Angeles was used in many important buildings including the famous Los Angeles City hall.  In Santa Barbara cast stone and Santa Barbara stone were used in conjunction in many historical buildings.  Santa Barbara stone also called Santa Barbara sandstone, is found mainly in Santa Barbara county, is removed from the ground in loose form, the Santa Barbara stone is then cut and shaped by a stonemason into useable blocks.  Cast stone in Beverly Hills was used in the Beverly Hills City hall and is now used on many residential buildings.  We also supply and install granite and CDI precast caststone and concrete design product,  CDI columns, Sierra stone caststone columns and balustrade, California precast products, CDI precast, CDI precast granite moldings and stairs. We also supply and  install CDI precast granite concrete window and door trim, CDI GFRC columns, Sierra stone products, concrete design, full weight precast and granite or limestone products,  California precast columns, CDI precast pool coping, CDI precast or limestone moldings and CDI fireplace mantles. We manufacture our own concrete molds.
 

 

Precast concrete
Precast concrete is usually used in lower end track homes where budget is a concern, cast stone is usually used in higher end homes where budget is not a major concern. The difference between cast stone and precast concrete is easily seen, and even the novice can appreciate the high quality limestone like finish on a cast stone product. Fireplace mantels or as some call them fireplace mantles look beautiful when constructed from cast stone. Cast stone fireplace mantels are used in any situation.  The fireplace mantels are both strong and fireproof. Fireplace mantels are a thing of beauty when made from cast stone or precast concrete. Fireplace mantels are also made from wood. Fireplace mantels or fireplace chimneys are the main feature in any room and a fireplace mantel made from cast stone or precast concrete is a sight to behold.
Cast stone by Ventura Cast Stone installed in California city's such as Los Angeles, Beverly Hills, Bel Air, Ventura or Santa Barbara has to be mechanically fastened to the wood frame of a building usually with stainless steel or galvanized attachments, this because of earthquake codes.  There are many historical buildings in California with cast stone as part of their facade.  Cast stone in Los Angeles, Beverly hills, Bel Air, Ventura and Santa Barbara was at it's most popular in the 1900's.  In Santa Barbara, cast stone was used extensively in the downtown district and also in a primitive form at the Santa Barbara mission in the form of adobe, a mixture of mud and straw or horsehair mixed with water and hand shaped into molds.  Cast stone in the City of Ventura was used mainly on churches in the downtown area.  Cast stone in Los Angeles was used in many important buildings including the famous Los Angeles City hall.  In Santa Barbara cast stone and Santa Barbara stone were used in conjunction in many historical buildings.  Santa Barbara stone also called Santa Barbara sandstone, is found mainly in Santa Barbara county, is removed from the ground in loose form, the Santa Barbara stone is then cut and shaped by a stonemason into useable blocks.  Cast stone in Beverly Hills was used in the Beverly Hills City hall and is now used on many residential buildings.  We also supply and install granite and CDI precast caststone and concrete design product,  CDI columns, Sierra stone caststone columns and balustrade, California precast products, CDI precast, CDI precast granite moldings and stairs. We also supply and  install CDI precast granite concrete window and door trim, CDI GFRC columns, Sierra stone products, concrete design, full weight precast and granite or limestone products,  California precast columns, CDI precast pool coping, CDI precast or limestone moldings and CDI fireplace mantles.
We also install the products exclusively manufactured by other company's including, Sierra concrete design, Sierra stone and Dura art stone, Stone legends, Moonlight molds, Fineline precast, Concrete design inc. Studio cast design, Concrete design inc, CDI, Architectural products, Haddonstone.

 These products include: cast stone, limestone, precast concrete, precast, cast, stone, limestone, sandstone, los angeles, ventura, santa barbara, los angeles precast, los angeles columns, los angeles cast stone, santa barbara precast, santa barbara cast stone, santa barbara stone, santa barbara columns, ventura cast stone, ventura precast, ventura columns, ventura stone. These products include: cast stone, limestone, precast concrete, precast, cast, stone, limestone, sandstone, los angeles, ventura, santa barbara, los angeles precast, los angeles columns, los angeles cast stone, santa barbara precast, santa barbara cast stone, santa barbara stone, santa barbara columns, ventura cast stone, ventura precast, ventura columns, ventura stone, concrete molds.

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About Ventura Cast Stone
 

Cast stone

We are pleased to introduce a new line of Tuscan moldings, taken from actual moldings from the Villas and grand homes of the Tuscany region of Italy.

 

Ventura Cast Stone product, is a truly superior alternative to natural cut building stone. Combined with its ability to simulate or reproduce an almost limitless variety of natural stones, Cast Stone offers many advantages over cut stone. Cast Stone can be integrally reinforced with steel and precisely colored through aggregates or mineral oxides. Mix designs have tested engineering values which result in a predictable durable life.

Cast stone is a highly refined architectural precast concrete stone manufactured to simulate natural cut stone. It is a masonry product that provides architectural trim and ornamentation. Used for centuries in Europe and in the United States in the 1900s, cast stone has gained widespread acceptance in the architectural community as a suitable replacement for many masonry materials and for all types of natural cut building stones. Continental Cast Stone manufactures cast stone using the VDT (vibrant dry tamp) method. A zero slump mix is compacted into a rigid mold, resulting in a finish that is virtually indistinguishable from quarried limestone. The primary advantage of this method is that it virtually guarantees the absence of air voids (also known as "bug holes") on the surface. Cast stone made by the company meets the requirements of ASTM C-1364, the Standard Specification for Architectural Cast Stone.

 

Strength and weathering qualities are consistently better than natural stone because the manufacturing process is controlled. Properties such as these cannot be assured in a quarried building stone. Repetitive treatment, either as trim or ornament, can be achieved quite economically in Cast Stone. The ability of Cast Stone to replicate deteriorating natural stone on existing buildings makes it an ideal material for the remodeling or restoration of old structures.

 

Cast Stone is a highly refined architectural building stone, usually made up of white cement and a combination of various sizes aggregates of white marble, quartz, or other durable white stone. The aggregates are numerous and are meticulously graded by sieve analysis to produce a material that is dense and lack voids.

The cast material is impervious to moisture, and will test in compression to 6,000 psi and not over 5% water absorption. The surface skin of the cement on cast stone is removed to expose the white stone (or other) aggregates, which reflect and sparkle over the matrix.

Since cast stone is a type of architectural precast stone, the question is often asked: "What is the difference between cast stone and architectural precast concrete?" The short answer is that cast stone is used in place of natural stone. As a type of building stone, cast stone is specified under the masonry division 04720. It is usually set by a masonry contractor using standard building stone anchors. Perhaps most important, and unless otherwise specified, cast stone looks like natural stone, dimensional, cut building stone. Upon close examination, the finish of cast stone looks like limestone.

To distinguish its appearance from the "pebbly with voids" appearance normally associated with concrete. This dense finish is more resistant to weather and dirt, and the fine aggregates retain the granular texture through decades of exposure to the elements. The character of Cast Stone, made as described above, is similar in color, texture, and appearance to a good grade of natural cut limestone, but is stronger, since strength can be controlled through the manufacturing process and is more impervious to water, weather, and dirt. By controlling the proportion of white and /or gray cement, manufactured or natural sands, carefully selected crushed stone or well-graded natural gravel, and mineral coloring pigments, cast stone can be made to simulate perfectly many other natural cut building stones, such as brownstone, sandstone, bluestone, granite, slate, keystone, travertine, and others.

Our Cast Stone range of products are into two product types:

Dry Cast

The "Dry Cast" method is a two part process, a face material to give you the similar finish to natural stone. Mechanically compacted to the rear of this is the backing mix to give the units strength in the terms of handling ability

Dry cast units are immediately demoulded after casting and are hand finished to a very high standard.

Wet Cast

Wet Cast as the name suggests produces structural products like heads and sills but is also used for slabs, beams and other similar products, that are for high exposure or structural situations where greater loads are required on the finished unit. The Wet Cast also has the added advantage of specialist finishes with the use of special sand aggregates, a massive spectrum of colors can be achieved.

 

Introduction to Cast Stone (wet cast and dry cast)

Cast Stone as is in the British Standard is known by a variety of other names including art stone, reconstructed stone, reconstituted stone, artificial stone and manufactured stone. BS 1217 defines cast stone as any material manufactured with aggregate and cementicious binder and intended to resemble in appearance, and be used in a similar way to, natural stone. Cast stone is either homogenous through out or consists of a facing material and backing concrete.

The method of production is split into two categories.

bulletSemidry mixes
bulletPrecast concrete or sometimes referred to as 'wet' cast.

Choice of manufacturing method

The majority of cast stone manufactures use the semi-dry method of production. And is the more commonly widely used method of manufacture. Early consultation with us is advisable to ascertain the correct method of production for your project.

Sizes: Components produced using the semidry method are limited in size with face dimensions of Ashlar units normally no greater than 1200x600mm. This is mainly because of the fact a semi dry mix is used, which require rapid and rigorous compaction with hand held pneumatic tampers. The semidry method of production is best suited to traditionally sized ashlars quoins, sills, copings, door and window surrounds, etc.

Structural requirements: Components requiring reinforcement which is more complex than a few straight bars or a layer of fabric reinforcement, must be produced using the wet cast method of production. This is because it is difficult to achieve thorough compaction of semidry mixes around congested reinforcement.

Appearance: Cast stone can replicate a variety of stone colours and finishes. The semidry method of production is used to simulate limestones and sandstones. Where a component has a particularly intricate pattern or profile including slender projections, precast concrete may have to be used in preference to the 'semidry' method. Good colour matching between components can be achieved by both methods, although textural differences become apparent at close range.

Economics: Rapid production rates with frequent reuse of moulds are possible with cast stone produced using semidry mixes. Where as with the Wet Cast process a higher number of moulds is required to achieve the same casting program, but careful thought a planning stages of the contract can minimize the number of moulds. In Fact an additional 2-3 weeks extra lead-time for standard or semi standard products can sometimes be all that is needed to achieve the same casting program.

Comparison between the semidry and wet methods

The production of cast stone using semidry mixes differs from that of wet method in several ways.

Casting

Semi Dry ~ De-molding takes place immediately after compaction. This allows a rapid casting cycle with e.g. up to 100 or more basic components (sills, copings, etc.) a day from a single mould.

Wet Cast ~ Where as to manufacture the equivalent in wet cast it would not only take longer but you would require 1 mould per cast per day i.e. to produce 100 units a day you would need 100 moulds.

Semi Dry ~Compaction is carried out by pneumatic tampers rather than by vibration.

Wet Cast ~ Compaction is carried out by vibration.

Mixes

Semi Dry ~ *Separate facing and backing mixes are often used for components like ashlars, sills, heads and jambs, where the backing mix is concealed from view. Separate facing and backing mixes are used primarily to economize on the facing mix. BS1 217 requires a separate facing mix to be not less than 20 mm thick at any point, with semidry cement sand facing mixes and concrete backing mixes each mix is placed and compacted in immediate succession to ensure that they are effectively monolithic.

Wet Cast ~ Wet Cast units are manufactured from a through colored homogenous mix.

Semi Dry ~ Water repellent admixtures are invariably used in facing mixes to reduce permeability. Giving a water absorption of Grade B. All constituents are accurately weigh batched with the moisture content monitored regularly. Mix batches are necessarily small to prevent any premature drying of the mix. Thorough mixing and compaction are critical to ensure that the cast stone achieves the required density (typically between 1850-2100kg/m2), compressive strength and permeability.

Wet Cast ~ superplasticisers and accelerators are used to ensure good flow of the mix during vibration and compaction to achieve a smooth, compact and blow hole free finish (where ever possible finish smooth after dressing) also to give good early strength. Typical cube tests at 7-10 Days are that of the equivalent of that of a semi dry unit at 28 Days

Products are split into three categories.

Standard - Cast stone items that are manufactured in accordance with our Technical specification sheets. These items could be stock items or units, which are ready to cast at the first available production slot, with no moulds to produce. Products like standard head, cills or pier caps and copings. The cost of establishing the moulds is not same, thus for small production runs costs can be kept to the minimum. Also not forgetting lead times can be much shorter by not having to detail, obtain approval and then construct moulds.

Semi Standard - Cast stone items, which are similar to details within our Technical specification sheets. But say vary in length or require slight mould adaptation or modification.

Purpose Made - Cast Stone items which are manufactured in accordance with the contract documents. These units are made from new purpose made moulds. These would probably be specialised units, which are not contained in our brochure. We have our own in house design department, who will assist you in the process of your design advising you in Careful thought must be given in the planning process for purpose made products. The following points should be bore in mind before hand.

bulletDesign and detailing of in house production drawings- Some times it is of necessity to produce working drawings of Architects details to enable production of moulds.

This process can some times take any thing from 2 10 days, dependant on how long it takes to get details approved.

 

bulletApproval of production drawings.

 

bulletProduction of Patterns- Sometimes it is necessary to produce units from G.R.P. or Rubber moulds.

 

bulletThis may involve the pattern being produced and before moulds are manufactured, approval of the pattern may be sort from the Architect or Client.

 

bulletApproval of production patterns

 

bulletManufacture of molds

 

bulletProduction of Units

 

bulletCuring of units

 

bulletPackaging and Transportation to Site

 

Remember adequate time must be allowed for all of the above to be in accordance with B.S.1217

Colors and Finishes

Natural stone colors are achieved either by reliance on the color of crushed rock and sands and aggregates or by the addition of pigments. White cement gray cement and a combination are often used. The use of pigments can give the cast stone greater scope in the selection of suitably graded aggregates, which permit good compaction and achieve a strong, dense mix. Iron oxides based pigments are normally used in small quantities (e.g. 0.2%-1% yellow iron oxide by weight of cement for yellow sandstone's and up to 5% red iron oxide for red sandstone). High proportions of pigment powder (above say 6 - 8% by weight of cement) are used sometimes to achieve unusual colors like blues and browns but generally these should be avoided.

A variety of traditional ashlar finishes can be replicated with cast stone, including plain, boasted, tooled, rockfaced, vermiculated. The other ashlar finishes are normally produced from latex:sand mould liners.

bulletSemi Dry ~ Plain finishes normally produced using sealed plywood mould liners or, where the shape, detail or longevity for mould dictates, fiberglass is used.
bulletWet Cast ~ unlike the semidry method, the wet cast mix produces a surface laitance which has to be removed after demoulding to reveal the color and texture of the fines layer. The laitance is removed by either acid etching or retarding the surface within the mould prior to curing and washing off after demolding to achieve a smaller large expose of aggregate.

Here is where specialist aggregates can be used to achieve some wonderful and varied finishes and colors.

Structural Use

Dependant on the situation all cast stone both Wet and Dry Cast can be used. But there are limitations in the Dry Cast process as opposed to Wet Cast: -

bulletSemi Dry ~ Components requiring reinforcement which is more complex than a few straight bars or a layer of fabric reinforcement are not possible. This is because it is difficult to achieve thorough compaction of semidry mixes using a pneumatic tamper in and around the congested reinforcement. Therefore Wet Cast is the option.
 
bulletWet Cast ~ unlike the semidry method, the Wet Cast mix is poured into the mould as thick liquid mix and compaction is achieved by vibration. So even the more complex arrangement of bars can be compacted sufficiently. The added advantage being the need to put any secondary support like pressed or fabricated steel lintel saving costs. Also we can manufacture structural beams for larger vehicle entranceways for example.

 

 
Since its introduction in 1969, GFRC has matured and today's designer has available to him, depending upon his performance requirements, and a range of matrix modifiers such as acrylic polymers, rapid set cements and additives to improve the long-term stability of the material. Extensive independent test and performance data are available on all aspects of matrix formulation.

This environmentally friendly composite, with its low consumption of energy and natural raw materials, is being formed into a great variety of products and has won firm friends amongst designers, architects, engineers and end users for its flexible ability to meet performance, appearance and cost parameters.

With GFRC, architects and designers have the ability to create and innovate totally integrated projects, not only in the buildings they design, but also with the surroundings in which they are located. The lightness of GFRC relative to many other cladding materials is a factor well worth taking into account in the initial calculations. This aspect is brought into even sharper focus when considering site carnage particularly on multi-story buildings in congested city centers. GFRC panels can cover 3 or 4 times the area of precast concrete panels of the same weight, or permit lower capacity cranes the necessary outreach to handle units of economical size throughout the whole 3600. GFRC has the ability to provided shape, color and textures desired by specifiers and architects alike, with in the unit. Thus eliminating the need to paint any of the surfaces and in turn reducing the life cycle cost of the façade. Usually the only routine maintenance necessary is periodic washing and cleaning. Carefully constructed moulds in metal, timber, plastics or synthetic rubber can provide the means of achieving an almost limitless variety of surface textures, from highly disciplined patterns to freeform art, heraldry and ornamental detail.

Glass fiber reinforced cement, generally referred to as G.F.R.C. is a combination of alkali resistant drawn glass fiber (A.R.G.) and a cement based matrix.

Glass reinforced concrete is a tough cement-based material with a high strength to weight ratio. It can be molded into a variety of complex shapes to accommodate an immense range of Architectural and Engineering applications, such as wall claddings for multi-stored reinforced concrete or structural steel frames, sound absorption barriers for main roads, flyovers and piping etc. etc. The applications are endless.

Cast Stone is comparable to natural stone as a building material in both appearance and performance, yet it is readily available and provides a cost effective alternative on projects from simple domestic housing to complicated schemes such as commercial buildings and cathedrals. It can be formed to almost any shape and size the designer wishes and can equal, or even surpass, the technical capabilities of natural stone in terms of strength, moisture penetration and coloring. It is ideal for both new build and refurbishment work particularly in areas of sensitive planning constraints or where stone is a predominant building material.

Cast Stone is any product manufactured with aggregate and cementitious binder intended to resemble and be used in a similar way to natural stone. Cast Stone is either homogenous throughout or consists of a facing and backing mix.

It is produced either as a semi-dry process which gives components a slightly open textured face, similar to sawn natural stone, or as a wet cast process which gives a much closer face texture and allows large components and those with complex reinforcement to be produced. Our cast stone process continues manufacturing traditions dating back to before the turn of the century whilst incorporating modern production techniques to both reduce costs and provide a superior product. Many units are hand crafted to ensure a high quality finish.


 

 

Welcome to a pt!  The table template that accompanies this set is variable width, and will adjust to full screen vi

PART 1 - GENERAL

1.1  FABRICATOR: The Fabricator shall have a minimum of 5 years successful experience in fabrication of integrally colored architectural Cast Stone units, similar to units required for this project.

  1. Steps Plus, Inc., 6375 Thompson Rd., Syracuse, NY 13206, web: steps-plus.com, ph.: 315-432-0806, fax: 315-432-0612.
  2. Any fabricator that can submit literature and test reports showing that they can meet the requirements of this specification.

1.2  SUBMITTALS:

  1. Fabricator information as listed above under section 1.1-B if the proposed fabricator is not already listed as a qualified manufacturer above.
  2. Shop Drawings showing layout, dimensions, and identification of each Cast Stone unit corresponding to sequence and procedure of installation. The Fabricator shall submit the shop drawings to the General Contractor who shall verify all drawing dimensions and coordinate the shop drawings with field conditions and other trades. The General Contractor shall submit the shop drawings to the Architect for approval.
  3. Samples: Minimum size - 6" x 6" x 2" to illustrate the quality, color, and surface finish texture. Fabricator must develop a custom colored mix to match a colored sample provided by the Architect. The color sample to match would either be an earthtone color shade (such as: Indiana limestone color, off-white, buff, brown, brick orange, brick red, light gray, dark gray, dull yellow) or pure white. Painted, stained, or coated Cast Stone is not acceptable. Unless otherwise noted, all the Cast Stone units on the project will be the same color and of the same mix design. Smooth, dense, fine-grained texture achieved by acid etching or lightly sandblasting to thoroughly remove all surface cement paste.

PART 2 - PRODUCTS

2.1  MATERIALS

  1. Portland Cement: ASTM C 150, Type I or Type III, Color to be white or gray as required to achieve proper color as determined by the Architect.
  2. Coarse Aggregate: ASTM C 33, Color to be white. Darker aggregates may be used as long as the proper color mix is achieved as determined by the Architect.
  3. Fine Aggregate: ASTM C 33, Color to be white. Darker aggregates may be used as long as the proper color mix is achieved as determined by the Architect.
  4. Pigments: ASTM C 979; Inorganic, nonfading, resistant to lime and other alkalis. Pigments not to exceed 10% of the cement weight.
  5. Water: Drinkable, free from foreign materials in amounts harmful to concrete or cast in steel.
  6. Air-Entraining Admixture: ASTM C 260.
  7. Water-Reducing, Retarding, or Accelerating Admixtures: ASTM C 494, type as selected by Fabricator and containing not more than 0.1 percent chloride ions.
  8. Reinforcement: New billet steel reinforcing bars, as necessary for safe handling, setting and structural stress. Size of the reinforcing shall be specified with a minimum area of steel equal to one quarter of one percent of the cross section area. If the surfaces are to be exposed to the weather, the reinforcement shall be galvanized or epoxy coated when covered with less than 2 inches of material for bars larger than 5/8 inch and 1-1/2 inches for bars 5/8 inch or smaller. The material covering in all cases shall be at least twice the diameter of the bars.
    1. Reinforcing Bars: ASTM A 615, Grade 60, deformed.
    2. Epoxy-Coated Reinforcing Bars: ASTM A 775.
    3. Galvanized Reinforcing Bars: ASTM A 767, Class II (2.0 oz. zinc psf), hot-dip galvanized after fabrication and bending.
    4. Welded Wire Fabric: ASTM A 185.
  9. Anchorages: The Setting Contractor is to provide all loose hardware (dowels, anchors, plates, etc.) necessary for securing Cast Stone units to supporting and/or adjacent members. Anchors to be non-corrosive; galvanized, brass or stainless steel type 304.

2.2  MIX PROPERTIES: Minimum 6000 psi compressive strength at 28 days using 6" x 12" cylinders per ASTM C39-86; Total Air Content not less than 4% nor more than 7%; Water Absorption is not to exceed 5% by weight when tested per ASTM C 642.

2.3  SURFACE FINISH: Remove all surface cement paste by means of acid etching or lightly sandblasting to provide a smooth, dense, fine-grained texture with no streaks or blotches. Texture and quality of finish to be generally equal to the approved sample when viewed in direct daylight at a 10 foot distance.

 

PART 3 - EXECUTION

3.1 INSTALLATION

  1. Anchorages: The Setting Contractor is to provide loose steel plates, clip angles, seat angles, anchors, dowels, cramps, hangers, and other miscellaneous loose steel shapes not provided by other trades, necessary for securing Cast Stone units to supporting and/or adjacent members.
  2. Do not install any Cast Stone units that have any defects that exceed the acceptable PCI MNL-117 tolerances for dimensions and color if installation would result in unsatisfactory performance or appearance in the opinion of the Architect.
  3. Install Cast Stone concrete members plumb, level, and in alignment in accordance with PCI MNL-117 erection tolerances and the contract documents Provide temporary supports and bracing as required to maintain position, stability, and alignment as members are being permanently connected.
  4. Protect the Cast Stone units from discoloration and staining when washing down the surrounding masonry by covering the Cast Stone units with plastic sheeting and/or by thoroughly soaking them with clear water to prevent dirty washdown water from being absorbed into them. If dirty washdown water gets on the Cast Stone, hose it off immediately with clear water.
  5. Patching: The repair of chipped or damaged Cast Stone shall be done with materials and instructions furnished by the Fabricator. The Cast Stone shall show no obvious repairs or imperfections other than minimal color variations when viewed with the unaided eye under good typical day lighting at a 20 foot distance.
  6. Cleaning: Before pointing and/or caulking, the face of all Cast Stone shall be scrubbed with a fiber brush, using mild detergent and water and shall then be thoroughly rinsed with clean running water. Any mortar on the face of the Cast Stone shall be removed. No acids or prepared cleaners shall be used without the approval of the Cast Stone Fabricator.

3.2 PERFORMANCE REQUIREMENTS

  1. Applicable standards for inspection and quality control shall be PCI MNL - 117 "Manual for Quality Control for Plants and Production of Architectural Precast Concrete Products" and PCI's "Architectural Precast Concrete Design Manual, 2nd Edition".
  2. The Architectural Cast Stone units shall show no obvious repairs or imperfections other than minimal color variations when viewed with the unaided eye at a 20 foot distance in good typical daylight illumination.
  3. Any unacceptable Cast Stone units that can not be repaired to the Architect's satisfaction in accordance with the aforementioned criteria are deemed unacceptable and are to be replaced by the Contractor.

 

 

Ventura Cast Stone product, is a truly superior alternative to natural cut building stone. Combined with its ability to simulate or reproduce an almost limitless variety of natural stones, Cast Stone offers many advantages over cut stone. Cast Stone can be integrally reinforced with steel and precisely colored through aggregates or mineral oxides. Mix designs have tested engineering values which result in a predictable durable life.

Cast stone is a highly refined architectural precast concrete stone manufactured to simulate natural cut stone. It is a masonry product that provides architectural trim and ornamentation. Used for centuries in Europe and in the United States in the 1900s, cast stone has gained widespread acceptance in the architectural community as a suitable replacement for many masonry materials and for all types of natural cut building stones. Continental Cast Stone manufactures cast stone using the VDT (vibrant dry tamp) method. A zero slump mix is compacted into a rigid mold, resulting in a finish that is virtually indistinguishable from quarried limestone. The primary advantage of this method is that it virtually guarantees the absence of air voids (also known as "bug holes") on the surface. Cast stone made by the company meets the requirements of ASTM C-1364, the Standard Specification for Architectural Cast Stone.

 

Strength and weathering qualities are consistently better than natural stone because the manufacturing process is controlled. Properties such as these cannot be assured in a quarried building stone. Repetitive treatment, either as trim or ornament, can be achieved quite economically in Cast Stone. The ability of Cast Stone to replicate deteriorating natural stone on existing buildings makes it an ideal material for the remodeling or restoration of old structures.

 

Cast Stone is a highly refined architectural building stone, usually made up of white cement and a combination of various sizes aggregates of white marble, quartz, or other durable white stone. The aggregates are numerous and are meticulously graded by sieve analysis to produce a material that is dense and lack voids.

The cast material is impervious to moisture, and will test in compression to 6,000 psi and not over 5% water absorption. The surface skin of the cement on cast stone is removed to expose the white stone (or other) aggregates, which reflect and sparkle over the matrix.

Since cast stone is a type of architectural precast stone, the question is often asked: "What is the difference between cast stone and architectural precast concrete?" The short answer is that cast stone is used in place of natural stone. As a type of building stone, cast stone is specified under the masonry division 04720. It is usually set by a masonry contractor using standard building stone anchors. Perhaps most important, and unless otherwise specified, cast stone looks like natural stone, dimensional, cut building stone. Upon close examination, the finish of cast stone looks like limestone.

To distinguish its appearance from the "pebbly with voids" appearance normally associated with concrete. This dense finish is more resistant to weather and dirt, and the fine aggregates retain the granular texture through decades of exposure to the elements. The character of Cast Stone, made as described above, is similar in color, texture, and appearance to a good grade of natural cut limestone, but is stronger, since strength can be controlled through the manufacturing process and is more impervious to water, weather, and dirt. By controlling the proportion of white and /or gray cement, manufactured or natural sands, carefully selected crushed stone or well-graded natural gravel, and mineral coloring pigments, cast stone can be made to simulate perfectly many other natural cut building stones, such as brownstone, sandstone, bluestone, granite, slate, keystone, travertine, and others.

 
Precast concrete
Precast concrete is usually used in lower end track homes where budget is a concern, cast stone is usually used in higher end homes where budget is not a major concern. The difference between cast stone and precast concrete is easily seen, and even the novice can appreciate the high quality limestone like finish on a cast stone product. Fireplace mantels or as some call them fireplace mantles look beautiful when constructed from cast stone. Cast stone fireplace mantels are used in any situation.  The fireplace mantels are both strong and fireproof. Fireplace mantels are a thing of beauty when made from cast stone or precast concrete. Fireplace mantels are also made from wood. Fireplace mantels or fireplace chimneys are the main feature in any room and a fireplace mantel made from cast stone or precast concrete is a sight to behold.
Cast stone by Ventura Cast Stone installed in California city's such as Los Angeles, Beverly Hills, Bel Air, Ventura or Santa Barbara has to be mechanically fastened to the wood frame of a building usually with stainless steel or galvanized attachments, this because of earthquake codes.  There are many historical buildings in California with cast stone as part of their facade.  Cast stone in Los Angeles, Beverly hills, Bel Air, Ventura and Santa Barbara was at it's most popular in the 1900's.  In Santa Barbara, cast stone was used extensively in the downtown district and also in a primitive form at the Santa Barbara mission in the form of adobe, a mixture of mud and straw or horsehair mixed with water and hand shaped into molds.  Cast stone in the City of Ventura was used mainly on churches in the downtown area.  Cast stone in Los Angeles was used in many important buildings including the famous Los Angeles City hall.  In Santa Barbara cast stone and Santa Barbara stone were used in conjunction in many historical buildings.  Santa Barbara stone also called Santa Barbara sandstone, is found mainly in Santa Barbara county, is removed from the ground in loose form, the Santa Barbara stone is then cut and shaped by a stonemason into useable blocks.  Cast stone in Beverly Hills was used in the Beverly Hills City hall and is now used on many residential buildings.  We also supply and install granite and CDI precast caststone and concrete design product,  CDI columns, Sierra stone caststone columns and balustrade, California precast products, CDI precast, CDI precast granite moldings and stairs. We also supply and  install CDI precast granite concrete window and door trim, CDI GFRC columns, Sierra stone products, concrete design, full weight precast and granite or limestone products,  Malibu California precast columns, CDI precast pool coping, CDI precast or limestone moldings and CDI fireplace mantles.
We also install the products exclusively manufactured by other company's including, Sierra concrete design, Sierra stone and Dura art stone, Stone legends, Moonlight molds, Fineline precast, Concrete design inc. Studio cast design, Concrete design inc, CDI, Architectural products, Haddonstone. These products include: cast stone, limestone, Malibu precast concrete, precast, cast, stone, limestone, sandstone, Malibu CA, los angeles, ventura, santa barbara, los angeles precast, los angeles columns, los angeles cast stone, santa barbara precast, santa barbara cast stone, santa barbara stone, santa barbara or Malibu columns, ventura cast stone, ventura or Malibu precast, ventura columns, ventura stone.

 These products include: cast stone, limestone, precast concrete, precast, cast stone,precast concrete,los angeles precast, ventura,santa barbara precast,los angeles columns,los angeles cast stone,santa barbara precast, santa barbara cast stone,santa barbara stone,santa barbara columns,ventura cast stone, ventura precast,ventura columns,ventura stonecast, stone, limestone, sandstone, los angeles, ventura, santa barbara, los angeles precast, los angeles columns, los angeles cast stone, santa barbara precast, santa barbara cast stone, santa barbara stone, santa barbara columns, ventura cast stone, ventura precast, ventura columns, ventura stone, Malibu precast, Malibu stone, Malibu columns

Ventura Precast Concrete Colors
 

Precast concrete and GFRC colors

Ventura precast concrete colors are integral, the pigments are added to the cast stone or precast concrete mix as the aggregates are being mixed. this means the product can be cut or carved and the cut surface will be the same color as the rest of the product. With cast stone, the color and also the texture of the product will be very similar to the rest of the product. We use white cement which produces clean, bright colors
Color is one of the most important aspects of architectural precast concrete and cast stone. At Ventura cast stone we can design mixes to match items such as existing precast concrete and weather-stained limestone. We can also develop mixes with the correct color tone to match closely, existing cast stone or precast. This means we can reproduce almost any cast stone product, even 200 year old stone, limestone or sandstone. The color chips on this page represent just a small sampling of the colors we can achieve with our standard materials and pigments. We do not charge extra for standard colors or texture. Non-earthtone colors that require special pigments (such as blue and green) or non-stock aggregates do cost extra. Whether the goal is to match existing materials or to simply complement new stucco color, we are the company to turn to whenever high quality architectural precast concrete or cast stone items are required.

White Portland cement used in our product. It has essentially the same properties as gray cement, except for color, which is a very important quality control issue in the industry.

The color of white cement depends on raw materials and the manufacturing process. It is the metal oxides (primarily iron and manganese) that influence the whiteness and undertone of the material. White cement is manufactured to conform to ASTM C 150, Specification for Portland Cement. Although Types I, II, III, and V white cements are produced, Types I and III are the most common.

White cements produce clean, bright colors, especially for light pastels. Many different colors can be created by adding pigments to concrete made with white portland cement. Two or more pigments can be combined to achieve a wide range of colors. White cement (or a mixture of white and gray cement) can be specified to provide a consistent color of choice. An even greater variety of decorative looks can be achieved by using colored aggregates and varying the surface finish treatment or texture.

Mix designs for white or colored concrete are formulated based on each ingredient's effect on cast stone and precast concrete color:

bulletType and color of cement
bulletType and dosage of pigment
bulletType and dosage of admixtures
bulletType, gradation, color, and cleanliness of fine and coarse aggregates
bulletConsistent proportions, especially maintaining a uniform water-cement ratio

For every architectural project, once a mix design has been developed, sample panels should be built at the job site. These mockups serve as references for color and overall surface appearance.

White High-Performance Concrete (White HPC)

High-performance white concrete (such as high-strength or very low permeability concrete) adds high-tech appeal by incorporating materials like calcined clay (such as metakaolin), slag, or white silica fume into white cement concrete. Applications for HPC may include high-rise buildings, bridges, and parking structures.
 

Supplementary cementing materials may slightly alter the color of hardened concrete. Color effects are related to the color and amount of the material used in concrete. Many supplementary cementing materials resemble the color of Portland cement and therefore have little effect on color of the hardened concrete. Some silica fumes may give concrete a slightly bluish or dark gray tint and tan fly ash may impart a tan color to concrete when used in large quantities. Ground slag and metakaolin can make concrete whiter. Ground slag can initially impart a bluish or greenish undertone.


Natural and synthetic materials are used to color concrete for aesthetic and safety reasons. Red concrete is often used around buried electrical or gas lines as a warning to anyone near these facilities. Yellow concrete safety curbs are used in paving applications. Generally, the amount of pigments used in concrete should not exceed 10% by mass of the cement. Pigments used in amounts less than 6% generally do not affect concrete properties.

Unmodified carbon black substantially reduces air content. Most carbon black for coloring concrete contains an admixture to offset the effect on air. Before a coloring admixture is used at a project, it should be tested for color fastness in sunlight and autoclaving, chemical stability in cementing materials and effects on concrete properties. Calcium chloride should not be used with pigments to avoid color distortions. Pigments should conform to ASTM C 979.

The Romans referred to concrete as liquid stone. It was cement that allowed the most famous monuments and constructions of the ancient world to be completed, marking the most significant change in building design the world has ever seen. With the use of cement, architects were freed from the constraints of the past, from the limitations of quarried stone and its limited strength to size, from wood and the diminutive stature its buildings always possessed. Cement enabled the ancient architects to design with their imaginations, instead of their restrictions.

As anyone in the construction business surely knows, cement has not yet stopped evolving. The science of cement manufacture and production is continuing to make great strides, enabling new and imaginative processes to be invented.

Decorative concrete is on the forefront of this growth. With such techniques as dry pack cast stone, homeowners and designers can create an unlimited array of outdoor and textured surfaces and flooring options. These all enable the designers to escape the one flaw seen with concrete: as a finish material, its starkness can be downright plain. For instance, the durability of concrete makes it perfect for a driveway, patio, sidewalk or floor, so a means to "dress up" or disguise concrete without sacrificing any of the versatility is the goal of many of these manufacturers.

Integral color

One of the first ways to transform concrete is through integral coloring. This is where pigment, usually iron oxides, is added directly to the mixer. The mix is then poured normally, producing a colored slab of concrete that will not fade because the color is literally a part of the mix. These colors can range from subtle pinks and browns to deep blues and greens.

This is usually done by adding a precisely measured bag of pigment to the concrete, taking into consideration the amount of cement, total yardage of the truck and individual properties of the chosen pigment. The drawback of this dry add-mix is apparent when trying to attain the same color for different amounts of cement. Because the pigment attaches to the cement, the same pigment added to a five-sack mix will be much darker than that of an eight-sack mix.

"By using four distinct liquid pigments, added together in the correct ratio (similar to a four-color printing process), a huge variety of color is available," then we measure and test the resulting pigment for accuracy.

Integral color has many uses for the concrete industry. Concrete roof tiles, garden accessories and pre-fab concrete pipe are all starting to use integral coloring.

Other methods of coloring concrete are more appropriate for different applications. For instance, many companies make both dry and liquid color hardeners that can be scattered or sprayed on top of newly poured concrete, and once worked into the surface, strengthen the concrete while allowing the use of any color.

Acid staining

One of the most popular methods for decorating concrete today is with the use of acid staining. Many residential and commercial customers are using this method for obtaining a durable, beautiful and relatively inexpensive way to decorate their floors.

While this concept is not new (Frank Lloyd Wright used some acid stains), innovative ideas are expanding the range of the acid stained look. Multiple stains may be used to enhance the depth of the color, grout lines may be cut into the concrete to resemble tile, or highly detailed murals or rosettes may be stained for any surface outside or inside the home.

Coupled with staining and stamping, a number of options are available for designing decorative concrete. Indeed, all of the processes described here can be mixed and experimented with, limiting designers to only what they can imagine. There are a few places for the curious designer to experiment with these options.

Master Builders (www.masterbuilders.com) may be widely known for manufacturing concrete materials, but they have recently helped produce an interactive online test grounds (www.concretelifestyles.com). The site allows the user to swap patterns and colors to see different styles.

The most impressive thing in outdoor and indoor concrete today may be what has yet to be constructed.

 

 

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