Tilt-Up Cure and Bondbreaker Manual
Tilt-Up Cure & Bondbreaker Manual Contents Tilt-Up Cure and Bondbreaker Overview..............................1 SILCOSEAL Cure and Bondbreakers....................................... 2
TCA Award Winners.......................................................... 3 Project Photographs........................................................... 4
Understanding Bondbreaker Types..................................... 5 Water-Based Bondbreakers................................................. 6 By-products of Chemical Reactivity.................................... 6 Curing Properties of Bondbreakers..................................... 7
Resin Curing Compounds/Liquid Floor Hardeners.......... 11 Silcoseal Cure and Bondbreaker Use Options................ 12 Temporary Joint Filler...................................................... 13 Sealing Wood Reveals/Rustication Strips.......................... 13 Adhesives for Reveals/Rustication Strips........................... 13
Science of Bondbreakers
Application Procedures Silcoseal Cure Coat........................................................... 8 Silcoseal Bondbreaker Coat.......................................... 9-10
Revised 09/13/11
Circumstances Affecting Application Rate Stacked Panels.........................................................14 Pozzolans.................................................................14 Weather Conditions................................................15 Post-Lift Surface Preparation Wall Panel Preparation.............................................16 Floor Panel Preparation...........................................16 Additional Resources.........................................................17+
Nox-Crete’s History with Bondbreakers Nox-Crete has studied and developed bondbreaker technology for almost 40 years, and today, SILCOSEAL Cure and Bondbreakers remains among the top-selling bondbreakers in the world. Nox-Crete manufactured its first solvent based, chemically active cure and bondbreaker in 1973. Unique from hydrocarbon resin type or wax based bondbreakers at the time, SILCOSEAL 100, offered many performance advantages. SILCOSEAL 100 quickly became the product of choice for many large tilt-up contractors. Two years later, the formula was improved and SILCOSEAL 77 was introduced with faster dry times and better surface holdout. The product immediately impacted the tilt-up construction industry by providing improved panel appearance with uniform and consistent panel separation.
OVERVIEW
OVERVIEW
In 1989, a third generation cure and bondbreaker was born as concerns for clean air rose in California, one of the nation’s fastest growing tilt-up construction markets. SILCOSEAL 97E became the world’s first water based cure and bondbreaker. The industry was reluctant to change to a water-based product, however most tilt-up contractors who tried the new product actually preferred it to the more traditional solvent-based products. The passage of the Federal Clean Air Act in 1999 limited the amount of volatile organic compounds (VOC) present in all tilt-up bondbreakers sold in the United States. These new regulations gave manufacturers three alternatives: 1. Reduce solvent content by formulating water-based versions of their products. 2. Incorporate exempted and potentially carcinogenic solvents into their product formulations to replace the newly regulated solvents. 3. Pay the federal government a costly exceedence fee for each gallon of non-compliant product manufactured. Because SILCOSEAL 97E already met both the California and the less restrictive federal VOC requirements, Nox-Crete could focus on innovation. Two faster drying, water-based cure and bondbreakers were introduced in 1999, SILCOSEAL 2000F and SILCOSEAL 2000C. Both were designed with technology to improve resistance to the “osmotic effect,” minimizing panel surface defects during hot weather construction. In 2006, SILCOSEAL SELECT further improved emulsion stability with an innovative blend of faster drying solvents formulated to achieve a higher, less hazardous flash point, which eliminated the flammable shipping requirements. Throughout numerous product developments, Nox-Crete solidified its role as the industry leader of cure and bondbreakers. Most contractors experienced with Nox-Crete products agree that SILCOSEAL Cure and Bondbreakers out perform anything else on the market. SILCOSEAL Cure and Bondbreakers remain among the top-selling bondbreakers in the world.
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SILCOSEAL CURE AND BONDBREAKERS Chemically-active cure and bondbreaker available in three formulas: SILCOSEAL Select, SILCOSEAL 2000F and SILCOSEAL Classic. Advantages • Achieves exceptional panel appearance • Positive separation -- minimizes panel surface defects • Higher coverage rate results in lower applied cost
SILCOSEAL
SILCOSEAL
• Outstanding rain resistance that requires no reapplication after rain showers • Fast drying -- dries faster than most non-VOC compliant solvent based products • Excellent emulsion stability -- stays mixed longer • SILCOSEAL Select meets the modified moisture retention requirements of ASTM C309 when applied to a steel-troweled surface • Proper application results in minimal residue on casting slab and wall panel surfaces -- over application is easily removed without the use of expensive strippers • Does not contain wax which is difficult to remove and interferes with subsequent adhesion of floor and wall coverings • Protects against the osmotic effect Ideal For • Warehouses and distribution centers • Manufacturing facilities • Retail stores • Schools • Office complexes • Auditoriums, sports complexes and convention centers • Food processing and beverage bottling plants • Correctional facilities
Miami Children’s Museum - Miami, FL
Nordic Naturals - Watsonville, California
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TCA AWARD WINNERS
TCA AWARD WINNERS 2011 TCA AWARD WINNERS USE SILCOSEAL
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Muvico Village Entertainment Complex - Fredericksburg, VA
Iron Bridge Building III - Spokane, WA
FAA Facility - Miramar, FL
SILCOSEAL PROJECT PHOTOS
SILCOEAL PROJECT PHOTOS
City of Lauderhill Municipal Center - Lauderhill, FL
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Understanding Bondbreaker Types Bondbreakers are categorized into several different classes based on their composition and chemical reactivity. Though often categorized as membrane and non-membrane forming, all bondbreakers are capable of forming some type of membrane or film on the casting surface. Further, bondbreakers are characterized by their composition (water based or solvent based) and by their chemical activity (reactive or non-reactive). SILCOSEAL cure and bondbreakers are unlike any other bondbreakers on the market. SILCOSEAL is a water-based, reactive cure and bondbreaker. It contains additional proprietary solids that form a membrane, but the SILCOSEAL membrane does not transfer to panel faces like resin and wax-containing bondbreakers. Properly applied, SILCOSEAL does not stain or interfere with the adhesion of paints or coatings applied to wall or floor surfaces
Most other reactive bondbreakers provide less surface film accumulation when applied at the same coverage rates as SILCOSEAL. Today it is incorrect to label any bondbreaker as penetrating. Bondbreakers are applied to casting surfaces that have been burnished by power trowels. Regardless of the formula, the difference in penetration rates is almost immeasurable. Nox-Crete does not offer a penetrating cure and bondbreaker. It is thought that reactive bondbreakers are harder to remove than non-reactive bondbreakers. However, SILCOSEAL residue is easily removed from casting floor slab and wall panel surfaces Using enough bondbreaker to form a uniform film on the surface is critical to achieving a clean separation, regardless of the product type used. Use the following performance criteria when selecting the best bondbreaker for your application needs: dry time, rain resistance, curing properties, panel appearance, ease of residue removal, compatibility with hardeners/sealers and, of course, how well it breaks the bond.
SCIENCE OF BONDBREAKERS
SCIENCE OF BONDBREAKERS
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Water-Based Bondbreakers Water based bondbreakers are actually emulsions. They contain water, solvents and emulsifying agents that allow the water and solvent to mix. One characteristic of a water based bondbreaker is the length of time the product stays properly mixed. A quality bondbreaker will stay mixed for the entire workday. Bondbreakers that separate in a few hours can be difficult to apply properly and should be used with caution. Heat is also a factor in how long an emulsion will stay mixed. A new production of SILCOSEAL is formulated to stay completely mixed for approximately two weeks at 110 degrees Fahrenheit. SILCOSEAL SELECT will stay completely mixed for even longer. Emulsifying agents do break down over time and exposure to high temperatures can accelerate the deterioration of the emulsion. To ensure customers do not experience mixing problems, SILCOSEAL cure and bondbreakers are limited to a nine-month shelf life. Out of date product is not guaranteed to work properly and the warranty would no longer apply. The contractor should determine usability of the product according to the printed “Use By� date on each container. Other concerns often expressed when working with water based bondbreakers are dry time and ease of achieving a uniform application. SILCOSEAL cure and bondbreakers are formulated to dry quickly and develop uniform films on the casting slab surface.
By-Products of Chemical Reactivity SILCOSEAL cure and bondbreakers are chemically active. Some reaction will occur with slurries created by rainwater and concrete dust and even with rainwater and mineral deposits found in clay and dirt. The by-product of this reaction appears as a white deposit, almost like a film, on the casting slab. The deposit is typically well-bonded to the surface and, in most cases, does not need to be removed. Previous SILCOSEAL bondbreaker applications are not affected. SILCOSEAL bondbreaker can also be applied on top of the deposit as long as all loose dirt and other foreign matter is properly removed.
SCIENCE OF BONDBREAKERS
SCIENCE OF BONDBREAKERS
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Curing Properties of Bondbreakers All SILCOSEAL bondbreakers serve a dual function and act as both a cure and a bondbreaker. This dual purpose greatly reduces risk for incompatibility issues and application mistakes. Bondbreakers meeting the moisture retention requirements of ASTM C309 are generally considered suitable for use as a curing compound and bondbreaker in tilt-up construction.
A Closer Look At ASTM C309 ASTM C309, “Standard Specification for Liquid Membrane-Forming Compounds for Curing Concrete,” specifies a maximum moisture loss of 0.55 kg. per sq. meter. To test for moisture loss, use ASTM C156-98 Standard Test Method For Water Retention By Concrete Curing Materials. The test measures moisture loss in concrete with a wood screed finish. Unfortunately, a wood screed finish is not applicable to most tilt-up projects that have smooth, burnished, power-troweled finishes. To determine the curing needs of steel-troweled concrete, Nox-Crete selected Construction Technology Laboratories, Inc. (CTL), an independent testing laboratory, to perform a modified water retention test in general accordance with ASTM C156-98 to answer the following questions: 1. What is the difference in moisture loss between test specimens that received a wood screed finish and those that received a steel-trowel finish? CTL Test Result: Test specimens receiving a steel-trowel finish had a 24 percent reduction in moisture loss over the test specimens that received a wood float finish. 2. Does SILCOSEAL 2000F comply with the maximum moisture loss allowed by ASTM C309 when applied to steel-trowel finish? CTL Test Result: SILCOSEAL 2000F and SILCOSEAL SELECT meet the modified water retention requirement of ASTM C309, when applied to a steel-troweled surface.
SCIENCE OF BONDBREAKERS
SCIENCE OF BONDBREAKERS
Conclusion Properly applied, SILCOSEAL Cure and Bondbreakers provide the highest standard of curing performance to casting slab and topside panel surfaces. Residue is easily removed and, following proper cleaning procedures, will not interfere with the subsequent application of floor or wall paints, coatings or sealers. NOTE: Under excessively hot, dry and/or windy conditions, it may be necessary to wet cure or to use a higher performing curing compound such as Nox-Crete’s CURE & SEAL 1200E to further minimize the loss of moisture through the surface. For specific recommendations, contact Nox-Crete’s Customer Service Department.
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Silcoseal Cure Coat The following information is intended to provide a brief and simplified overview of the proper application procedures for SILCOSEAL. Prior to product application, please read and follow all use instructions and precautions provided in the product data sheet. The cure coat is crucial to a successful tilt-up project. Apply the cure coat immediately upon final finishing, preferably prior to joint saw cutting. Apply the SILCOSEAL cure coat with a hand pump sprayer or a low-pressure, high-volume power sprayer equipped with an 8004 LP or 8005 LP spray nozzle. The application rate for the cure coat typically ranges between 200 to 400 sf/gal (5-10 sm/l) but can vary widely depending on the type of concrete finish and ambient weather conditions.
ACI 305 Defined:
Hot Weather Concreting Any combination of the following conditions: • • • • •
High ambient temperature High concrete temperature Low relative humidity Wind speed Solar radiation
Over application of the cure coat can result in slow drying and delays. Under application can result in shrinkage, cracking, crazing, or excessively porous and weakened slab surfaces. In hot climate conditions, as defined by ACI 305, MONOFILM surface evaporation reducer is recommended. Apply MONOFILM immediately after laser screeding and again following bull floating. Additional applications of MONOFILM may be applied if necessary to reduce surface water evaporation.
APPLICATION PROCEDURES
APPLICATION PROCEDURES
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Silcoseal Bondbreaker Coats SILCOSEAL bondbreakers have almost two times the solids content of competing bondbreakers. Therefore, less SILCOSEAL is required than many competing products. The number of bondbreaker coats required and the application rate of each coat is directly related to the porosity of the casting slab and varies widely from one floor to the next. Many factors affect the porosity including concrete mix design, placing and finishing procedures and weather conditions during concrete placement. Because no slab surfaces are the same, it is impossible to specify an exact bondbreaker coverage rate. Use the following guidelines to ensure a proper uniform SILCOSEAL bondbreaker application: •
Inspect the casting slab/floor surfaces to ensure that all standing water, dirt, curing compound residue, wax, sawdust, spilled liquids and any other foreign contaminants are removed.
•
Spray two uniform bondbreaker coats of SILCOSEAL at 90-degree angles, or perpendicular, to each other. Allow the first coat to dry completely prior to applying the second coat. Equipment: Apply the bondbreaker coats using a hand pump sprayer or a lowpressure, high-volume power sprayer equipped with either an 8004 LP or 8005 LP spray nozzle. The combined effective coverage for all SILCOSEAL bondbreaker coats applied to new casting/flooring slabs previously cured with SILCOSEAL is 200 to 400 sf/gal (5-10 sm/l) but can vary widely depending upon the casting slab surface porosity.
Apply first and second coats at right angle for best results.
•
Back rolling is not required, but it will help yield a uniform application of SILCOSEAL bondbreaker, resulting in less discoloration of wall panel surfaces and less product required.
APPLICATION PROCEDURES
APPLICATION PROCEDURES
Equipment: To back roll use a Nox-Crete 18 inch roller applicator equipped with a 3/8 in. nap roller cover and telescopic handle. With light pressure, back roll the slab within one to two minutes of the spray application.
Perfect Form & Concrete Sprayer
Ideal Form & Concrete Sprayer
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Silcoseal Bondbreaker Coats Continued •
After the second coat, the treated casting/floor slab should appear dark in color and remain dark for a minimum of two to three hours. If light colored areas appear within two to three hours after application, the slab is excessively porous and requires additional bondbreaker coats. If light colored areas persist after applying additional coats of bondbreaker, thoroughly wet the affected areas with water to fill concrete pores and squeegee off excess water. After removing excess water, immediately apply another coat of SILCOSEAL. Repeat this process as necessary until the treated surfaces remain dark in color for a minimum of two to three hours.
•
SILCOSEAL bondbreaker produces a fully dried, uniform film with a dry, soap-like feel when properly applied,. Rubbing the treated surface should bring up small, cigarshaped pieces of bondbreaker. Over application of SILCOSEAL results in a wet, greasy feel to the touch. Over application should be avoided because it can result in wall panel surface retardation or dusting.
Important: Always obtain current product data from Nox-Crete and read thoroughly before product use.
APPLICATION PROCEDURES
APPLICATION PROCEDURES
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Resin Curing Compounds/Liquid Floor Hardeners Nox-Crete does not recommend using any other manufacturers curing compound in combination with SILCOSEAL bondbreakers. In certain instances, Nox-Crete may recommend one of its liquid floor hardeners or curing compounds such as: DURONOX, DURO-NOX LSC, CURE and SEAL 1200 E or RES-CURE DS with SILCOSEAL bondbreakers. Applying any product in combination with SILCOSEAL, may result in wall panel sticking or surface retardation problems, unless these precautions are followed: 1. Resin-based curing compounds or silicate-type liquid floor hardeners reduce the rain resistance of SILCOSEAL. To prevent sticking, carefully examine casting slab surfaces to ensure an adequate film of SILCOSEAL bondbreaker is present prior to panel concrete placement. 2. Casting slab surfaces cured with a resin-based compound or silicate-type liquid floor hardener scour easily during concrete placement. Protect casting slab surfaces from scouring with deflection boards or other methods that prevent direct discharge of concrete onto SILCOSEAL treated surfaces. 3. The application rate of SILCOSEAL bondbreakers is typically reduced when applied over resin based curing compounds or silicate type liquid floor hardeners. These products tend to seal the slab surface which reduces the surface porosity, resulting in less SILCOSEAL required. Over application of SILCOSEAL can result in wall panel surface dusting or retardation. Best results are obtained when SILCOSEAL is used as the casting slab cure and bondbreaker. However, if a resin-based cure or liquid floor hardener is to be applied to the casting slab surface prior to the bondbreaker, using one manufacturer for all products is the best guarantee to ensure product compatibility. When used properly, Nox-Crete guarantees the compatibility of its selected resin-based cures and silicate type liquid floor hardeners with SILCOSEAL tilt-up bondbreakers.
APPLICATION PROCEDURES
APPLICATION PROCEDURES
Please contact Nox-Crete for specific recommendations and additional information.
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Silcoseal Cure & Bondbreaker Use Options
OPTION 1
best
OPTION 2
better
OPTION 3
good
Meets Modified ASTM C309 For Steel-Troweled Surface
Immediately after final finishing, apply a cure coat of SILCOSEAL Apply additional bondbreaker coats of SILCOSEAL Prior to project completion, clean floor with BIO-CLEAN and apply any one of the DURO-NOX liquid floor hardeners.
Step 1
Tilt-up Panel SILCOSEAL Bondbreaker Coat SILCOSEAL Bondbreaker Coat SILCOSEAL Cure Coat Floor Slab
Step 2
DURO-NOX, DURO-NOX LS or DURO-NOX LSC Liquid Floor Hardener Clean With BIO-CLEAN/Water (1:3) & Floor Scrubbing Machine Floor Slab
Meets Modified ASTM C309 For Steel-Troweled Surface
Immediately after final finishing, apply DURO-NOX or DURO-NOX LSC liquid floor hardener followed by a cure coat of SILCOSEAL Apply additional bondbreaker coats of SILCOSEAL. Upon project completion, clean floor with BIO-CLEAN and apply a spiff coat of DURO-NOX or DURO-NOX LSC.
Step 1
Tilt-up Panel SILCOSEAL Bondbreaker Coat SILCOSEAL Bondbreaker Coat SILCOSEAL Cure Coat DURO-NOX or DURO-NOX LSC Liquid Hardener/Densifier/Sealer Floor Slab
Step 2
Spiff coat of DURO-NOX or DURO-NOX LSC Clean With BIO-CLEAN/Water (1:3) & Floor Scrubbing Machine Floor Slab
Meets Unmodified ASTM C-309
Immediately after final finishing, apply a cure coat of CURE & SEAL 1200E. Apply bondbreaker coats of SILCOSEAL Prior to project completion, clean floor with TSP detergent and water and apply a spiff coat of CURE & SEAL 1200E.
Step 1
Tilt-up Panel SILCOSEAL Bondbreaker Coat SILCOSEAL Bondbreaker Coat Cure Coat - CURE & SEAL 1200E Floor Slab
Step 2
Spiff Coat Of CURE & SEAL 1200E Clean With Trisodium Phosphate Detergent & Water Floor Slab
Warning: Many variables affect the application rates and product types required for a tilt-up project. Always review and follow manufacturer’s instructions found in product data sheets. For more information, recommendations and further resources, contact Nox-Crete.
NOX-CRETE PRODUCTS GROUP Omaha, Nebraska www.nox-crete.com (800) 669-2738 / (402) 341-1976
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Casting Slab Temporary Joint Filler Use Nox-Cretes TP Joint Filler to prevent wall-panel fins created by concrete seepage into new cut floor joints. TP Joint eliminates costly grinding associated with wall panel concrete seepage into saw-cut control joints. The slight recession formed in the wall panel when using TP Joint is easily patched with Nox-Crete’s PANEL PATCH.
Sealing Wood Reveals/Rustication Strips Dusty and stained concrete at reveals is a result of wood sugars retarding the concrete. Use Nox-Crete’s PRE-FORM, a non-permeable wood sealer, on all four sides of the reveal to prevent sugar retardation. Paints and acrylic sealers generally do not work.
Nox-Crete TP Joint
For best results, apply two coats of PRE-FORM (wet on wet) and allow to air dry for 24 hours prior to installing.
Adhesives for Reveals/Rustication Strips Nox-Crete tested 3Ms High-Strength 90 as an adhesive for wood reveals and rustication strips on concrete casting slabs treated with SILCOSEAL bondbreakers and recommends the following: •
Apply the adhesive to the wood only. Application of the adhesive to the concrete results in overspray that may be transferred to the tilt-up panel.
•
Apply two coats of adhesive, allowing 20 to 60 seconds between coats.
•
Wait one to two minutes before sticking the rustication strip to the concrete slab after the second coat.
Sugar retardation
These recommendations will allow for later bondbreaker applications and water saturations that will not affect product adhesion.
APPLICATION PROCEDURES
APPLICATION PROCEDURES
Use Nox-Crete’s BIO-CLEAN to remove the adhesive from the slab, . Apply undiluted BIOCLEAN and allow to sit for 10 to 15 minutes. Scrub with a nylon-bristled brush or broom and rinse with clean water.
Seal wood reveals and rustication strips with Nox-Crete PRE-FORM.
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Stacked Panels The topside of tilt-wall panels used as casting surfaces are generally more porous than floor slabs for several reasons. First, they are often finished with lighter weight trowels resulting in less burnished or more porous surfaces. Secondly, the cure coat and bondbreaker coats are typically applied to the top side of the stacked panel within 24 hours of when the panel was cast. This process gives the stacked panel concrete little chance to hydrate and develop the necessary calcium silicate gels that increase density and reduce surface porosity. This increased porosity often requires double the amount of SILCOSEAL than is normally needed to achieve a uniform bondbreaker film holdout on a traditional casting/floor slab surface.
Pozzolans Using pozzolans, including Class C and F Fly Ash and Blast Furnace Slag, in tilt-up concrete mix design is an increasingly popular sustainable building technique. Mix designs containing pozzolans in the range of 15 to 20 percent replacement for Portland cement are now commonplace, while mixes containing 30 to 50 percent fly ash are occasionally seen. When pozzolans are used in the casting/floor slab on a tilt-up project special guidelines need to be followed to ensure that SILCOSEAL provides the intended result. The use of any pozzolans as a replacement for Portland cement slows down concrete set time, delaying the finishing operation. During this time, critical mix water evaporates, resulting in a more porous surface, which requires more bondbreaker. In addition, pozzolans slow down the initial formation of calcium silicate gels that give concrete its strength, hardness and density. This delay results in a more porous casting/floor slab surface, which requires more bondbreaker compared to mix designs containing all Portland cement and no pozzolans.
SPECIAL CIRCUMSTANCES
SPECIAL CIRCUMSTANCES
Tilt-up contractors should plan on using as much as 25 percent or more SILCOSEAL bondbreaker than would normally be required on a typical Portland cement based casting slab. MONOFILM surface evaporation reducer is recommended to reduce the evaporation of critical mix water through the casting slab surface. (See Curing Coat on page 8) Casting slab floors containing pozzolans in excess of 15 percent of the total cementitious materials should be saturated with water prior to applying the SILCOSEAL bondbreaker coats. After saturating the slab, remove standing water with a squeegee or air compressor and immediately apply the first bondbreaker coat of SILCOSEAL. •
Nox-Crete recommends waiting a minimum of 21 days in warm weather conditions before placing concrete panels on casting slabs containing in excess of 15 percent pozzolans.
•
During colder temperatures, wait a minimum of 28 days.
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Weather Conditions Rain can cause applied bondbreaker coats to re-emulsify and wash away or to blister and peel. SILCOSEAL Cure and Bondbreakers offer excellent rain resistance and generally require no reapplication once dry, even if exposed to rain. However, applied coats of SILCOSEAL waterbased bondbreakers are vulnerable to re-emulsification if exposed to rain prior to drying. •
Under normal drying conditions, SILCOSEAL bondbreakers provide rain resistance after two hours of drying.
•
Under high humidity and cool temperatures, dry time is increased and SILCOSEAL bondbreakers provide rain resistance after 12 or more hours of drying.
•
Under low humidity and warmer temperatures, dry time is reduced and SILCOSEAL bondbreakers provide rain resistance after 1 hour of drying.
Due to a high permeability rating, SILCOSEAL cure and bondbreakers allow water vapor to easily pass through applied coats of bondbreaker, eliminating blistering or peeling. This allows application of SILCOSEAL without any concern for hydrostatic pressure and reduces the chance of bondbreaker coating failure. SILCOSEAL Cure and Bondbreakers are designed so wall panels can be placed within two weeks regardless of the weather conditions. If wall panels have not been placed on the SILCOSEAL treated surface within two weeks, additional coats of SILCOSEAL may be required to ensure sufficient bondbreaker film surface holdout on the casting surface.
SPECIAL CIRCUMSTANCES
SPECIAL CIRCUMSTANCES
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Wall Panel Preparation Many bondbreakers create an unsightly yellow or orange colored residue on panel surfaces that is designed to oxidize or dissipate in sunlight after 30-60 days of exposure. Unfortunately, not all panels receive the same amount of sunlight. For example, north-facing panels or panels shaded by adjacent structures do not oxidize or dissipate at the same rate and leave residue. Properly applied, SILCOSEAL bondbreakers produce clean panels, free of unsightly residue.
Wall Panel Preparation For Painting
Nox-Crete Panel Patch
All tilt-wall panels require some surface preparation for proper paint adhesion. To minimize preparation efforts, use a bondbreaker that leaves minimal residue, such as SILCOSEAL bondbreakers. Power washing panels is recommended to remove calcium carbonate (carbonation) that is frequently present as a white powder on the exterior panel surface. Power washing also opens the pores of the slick, cast surface to improve adhesion. Pretreating panel surfaces with a solution of trisodium phosphate (TSP) and water prior to power washing will remove any residual SILCOSEAL that resulted from over application. To mix the TSP and water solution, add .5 lbs (225 gms) of TSP per 1 gal (3.8 l) of water. Apply to the wall panel surface using a hand pump sprayer and allow to stand for 20 to 30 minutes. Rinse the TSP solution from the wall panel surface with water using a 3,000 to 4,000 psi pressure washer.
POST-LIFT SURFACE PREP
POST-LIFT SURFACE PREP
Use Nox-Crete’s PANEL PATCH to repair minor surface imperfections on wall panel surfaces prior to painting. PANEL PATCH dries fast and can be troweled or sanded smooth for seamless repairs.
Floor Panel Surface Preparation Silcoseal Cure and Bondbreakers are ideal for use on floors that ultimately receive a sealer or adhesive type floor covering. All reacted SILCOSEAL residue and any unreacted residue resulting from over-application is easily removed with a citrus cleaner and a floor-scrubbing machine.
BIO-CLEAN before and after
Simply dilute BIO-CLEAN, Nox-Crete’s citrus based cleaner, with one part BIOCLEAN and three parts water. Scrub the floor with an automatic floor scrubbing machine equipped with a nylo-grit scrub brush and rinse with clean water. Heavy accumulations of unreacted SILCOSEAL residue may require two or more passes. BIOCLEAN is equally effective at removing 3M adhesive residue grease, oil, dirt and black tire marks from the floor surface.
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ADDITIONAL RESOURCES RESOURCES ADDITIONAL
Drum Agitator Procedure
1
Center Bung
2
Insert drum agitator into center bung of drum and tighten threads
3
Snap on handle and mix thoroughly. (3/8 Or 1/2 drill can also be used, but handle turns very freely.)
NOTE: Always replace drum bung immediately after mixing and never leave drum open.
1/2 Square, Solid Steel Agitator with paddles
Partner Products for Tilt-Up Construction
Quality and Compatibility - Guaranteed.
When you choose Nox-Crete’s Tilt-Up Partner Products, you have our guarantee that the component products have been tested and designed to work together without compatibility issues. Because we believe in the quality and reliable performance of our Tilt-Up Partner Products, we offer a guarantee that goes beyond the standard “money back” offers. While we doubt that you will ever need the other benefits provided in our guarantee, they are part of the peace-of-mind that comes with choosing our Tilt-Up Partner Products. If there should happen to be a product failure or incompatibility between any of the component products, our experienced technical staff will work with you to find the cause of the problem and make a repair recommendation to help you get your project back on track. In addition, we will arrange for you to receive a full refund of your purchase price for the products which did not perform to our level of commitment to you. For more information, see our 100% Compatibility Guarantee.
hemical• •c
Tilt-Up Partner Product •
•
co mpatibility
Exterior Surfacing Compound Panel Patch
Fast drying, smooth textured, non-grit containing, Portland cement based, polymer modified surfacing compound
Tilt-Up Cure and Bondbreaker
Crack Control Floor Joint Fillers
New generation, water-based, chemically-active cure and bondbreaker for tilt-up concrete construction
Semi-rigid, epoxy/polyurethane copolymer floor joint filler
Silcoseal
Liquid Silicate Hardener, Sealer And Dustproofer
Dynaflex 502
Dynaflex JF-85
Semi-rigid, polyurea floor joint filler
Duro-Nox / Duro-Nox LS / Duro-Nox LSC
Clean Shave
Maximum performance, chemically-reactive, water-based hardener, sealer and dustproofer
Water-based, stain-blocking film for use during joint filler application
Floor Polishes
Surface Water Evaporation Reducer
Duro-Polish / Duro-Polish Plus Water-based, ultra-high gloss, concentrated, synthetic polymer floor polish
Exterior Wall Treatments Nox-Carb
Penetrating, pigmented, water-repellent sealer and stain for vertical exterior wall panels
Monofilm
Concentrated, water-based, surface water evaporation reducer for concrete
Temporary Joint Filler TP-Joint
Flexible, pre-molded temporary joint filler
TILT-UP CONSTRUCTION BRIEF 04/14/10
Recommended Application Procedures for SILCOSEAL Cure and Bondbreaker During Hot Weather Conditions Cure and bondbreaker application during hot weather conditions demands special consideration to ensure a successful result. Hot weather conditions necessitate additional care for adequate curing of the casting slab. Improperly cured casting slabs typically exhibit increased surface porosity and reduced surface strength. Normal application of the tilt-up bondbreaker to improperly cured casting slabs often results in inadequate surface accumulation of the bondbreaker. The addition of certain pozzolans such as fly ash can exacerbate the problem by slowing the concrete set time, thereby delaying the application of the curing compound and resulting in critical moisture loss. Recommended curing practices include the application of the bondbreaker cure coat IMMEDIATELY after final finishing and control joint cutting. The SILCOSEAL Cure and Bondbreaker cure coat application should be to the point of uniform surface film accumulation. Casting slab surfaces with increased porosity or surface area resulting from a rougher finish may require heavier applications of the cure coat to ensure adequate holdout and surface accumulation. In order for SILCOSEAL Cure and Bondbreaker to perform properly it is ESSENTIAL to develop a uniform surface accumulation on the casting slab. Proper application of the cure coat is the most important step towards ensuring adequate bondbreaker holdout on the successive bondbreaker coats. SILCOSEAL Cure and Bondbreaker applied as a cure coat chemically reacts with the surface concrete, forming a waterproof soap barrier which prevents successive bondbreaker coats from absorbing into the casting slab, thereby ensuring uniform holdout of the bondbreaker. If the cure coat application of SILCOSEAL Cure and Bondbreaker to the casting slab must be delayed or if the slab was not cured at all or is suspected of being porous, the surface should be saturated with water prior to the bondbreaker application. Excess water should be squeegeed off the surface immediately prior to the bondbreaker application. Saturating the casting slab with water in this manner will ensure that the SILCOSEAL Cure and Bondbreaker will achieve proper surface holdout. Following the cure coat application, it is necessary to apply successive bondbreaker coat(s) to the casting slab until the surface is uniformly dark in appearance with the presence of a “dry soap like feel” uniformly apparent to the touch over the entire casting slab surface with no indication of greater accumulations in low spots or depressions. Variations in concrete mix designs, weather conditions, finishing procedures and curing conditions make it impossible to predict the exact number of bondbreaker coats and/or application rates necessary to ensure adequate surface accumulation. Since each casting slab is inherently different, it is critical to the success of the project that the tilt-up contractor understands that during hot weather conditions it becomes more important than ever that the bondbreaker cure coat is properly applied and successive bondbreaker coats are applied until the “dry soap like feel” is uniformly apparent to the touch over the entire area. THE PRIMARY REASON FOR PANELS STICKING TO CASTING SLABS IS AN INADEQUATE FILM OF BONDBREAKER ON THE CASTING SLAB SURFACE AT THE TIME OF PANEL CONCRETE PLACEMENT. IT IS YOUR RESPONSIBILITY TO VERIFY THAT A CONTINUOUS FILM OF BONDBREAKER CAN BE FELT ON THE CASTING SLAB SURFACE, AS DESCRIBED ABOVE, IMMEDIATELY PRIOR TO THE PLACEMENT OF PANEL CONCRETE. PLEASE READ THE APPROPRIATE PRODUCT TECHNICAL BULLETINS AND USE INSTRUCTIONS PRIOR TO USE.
TILT-UP CONSTRUCTION BRIEF 04/14/10
POZZOLANS Used in Concrete Floor/Casting Slab Mix Designs (Fly Ash, Blast Furnace Slag and Silica Fume)
In the tilt-up construction industry, pozzolan containing concrete mix designs are becoming more common. The following are Nox-Crete’s recommendations when pozzolan containing concrete mixes are used in conjunction with Nox-Crete’s Silcoseal bondbreakers. 1. Pozzolans are commonly used in casting slab concrete mixes but are not generally used in wall panel concrete mix designs due to the resulting delay in strength development. 2. Concrete mixes containing pozzolans typically bleed less than conventional concrete mixes containing only Portland cement. With less or no bleed water available at the concrete surface to evaporate, the floor/casting slab is more susceptible to plastic shrinkage cracking, surface crusting, as well as increased slab surface porosity. To minimize these potential problems, as well as future problems relating to bondbreaker application and performance, the use of an evaporation reducer such as Nox-Crete’s Monofilm is absolutely essential. Contact Nox-Crete for specific details on the use of Monofilm. 3. Contractors generally should plan on the need for more bondbreaker on casting slabs incorporating pozzolans. On any tilt-up casting slab it is imperative that the bondbreaker be applied at a rate that is sufficient enough to result in a uniform film that is visibly and physically apparent across the entire casting slab surface. Since casting slabs that incorporate pozzolans tend to be more porous on the surface, the contractor may need to apply an extra 25 percent or more bondbreaker than is typical on a straight Portland cement based casting slab to obtain a uniform and adequate bondbreaker film on the slab surface and, ultimately, to ensure proper panel separation. 4. To further ensure proper panel separation from casting slabs containing pozzolans, it is strongly recommended that the casting slab area be thoroughly wetted with water immediately prior to panel concrete placement. This is especially important during warmer weather conditions. 5. The application of the cure on a casting slab containing pozzolans is perhaps the single most important step in the concrete placement process. Accordingly, it is extremely important that the cure is applied immediately upon completion of the final finishing and is done so in a manner that results in a uniform and adequate film across the entire slab surface. The successful use of Nox-Crete’s Silcoseal bondbreakers requires the use of curing compounds that are compatible. Nox-Crete’s Silcoseal bondbreakers have been formulated to work as both a curing compound as well as a bondbreaker and, therefore, should always be used as a system to ensure that the casting slab is properly cured and that good panel separation from the casting slab is obtained. 6. Pozzolan containing concrete mixes take longer to gain strength and to develop proper gel formation within the cementitious matrix. Therefore, it is recommended that the contractor wait a minimum of 21 days in warm weather conditions before placing concrete panels on a casting slab containing in excess of 15 percent pozzolans (total cement and pozzolans). During cooler temperatures, contractors should wait a minimum of 28 days.
TILT-UP CONSTRUCTION BRIEF 04/14/10
How to Avoid the Osmotic Effect The “Osmotic Effect” refers to migration of water out of a tilt-up panel and into the casting slab during the critical panel concrete hydration process. A gradient is formed when wet concrete from a freshly poured panel is cast against a casting slab with a lower water content. This results in water being drawn out of the panel and into the casting slab through a process called osmosis. The moisture concentration difference between the panel and casting slab is directly related to the osmotic force or pressure attained to reach equilibrium between the two slabs. The occurrence of osmosis is further exacerbated by the force of gravity which naturally pulls water out of the panel and into the casting slab as well as by a temperature gradient which often exists between cooler freshly placed concrete and a warmer casting slab. As the casting slab cools, water is naturally drawn out of the panel and into the casting slab. The “Osmotic Effect” is the incomplete hydration of the cement on the down side panel surface resulting from the loss of water due to migration into the casting slab through osmosis. Damage caused by the “Osmotic Effect” can range from minor panel surface defects such as dusting to complete skin pull-off as deep as 1/16 inch in depth in the more severe cases. Nox-Crete has devoted an enormous amount of time conducting field research on the cause and corrective action necessary to prevent the “Osmotic Effect”. The most effective means for preventing the “Osmotic Effect” is to eliminate the gradient differential by saturating the casting slab with water prior to the placement of the panel concrete and to use a chemically active breathable type cure and bondbreaker. Saturating the casting slab thoroughly with water before placement of the panel concrete increases the water concentration in the casting slab thereby effectively eliminating osmosis from occurring by eliminating the gradient. Field results indicate a reduction in the “Osmotic Effect” with an increase in downside panel surface strength. It should be noted that a light fogging of the casting slab with water immediately prior to the placement of the panel concrete showed only slight reduction in the “Osmotic Effect”. Best results were achieved when the casting slab was thoroughly saturated with water prior to panel concrete placement. Excess water on the casting slab must be removed immediately prior to the panel concrete placement to avoid the reverse effect of too much water which can result in surface dusting. In addition to saturating the casting slab with water, it is equally important to choose the right cure and bondbreaker. Best results are achieved if a chemically active, breathable type cure and bondbreaker is selected. Chemically active cure and bondbreakers reduce water migration through the bondbreaker while also permitting vapor transmission. Acrylic or hydrocarbon resin type membrane forming cure and bondbreakers form barriers which prevent water penetration, but also restrict water vapor transmission. Chemically active SILCOSEAL Cure and Bondbreaker, properly applied to a uniform surface accumulation, will reduce the penetration of mixing water into the casting slab without significantly affecting water vapor transmission through the surface. In addition, due to their ability to breath, casting slab surfaces coated with SILCOSEAL Cure and Bondbreaker provide excellent weatherability and are not subject to peeling, blistering, or delamination when exposed to rain water prior to placement of panel concrete. The use of silicate based hardeners, sealers, and dustproofers, such as DURO-NOX, used in conjunction with SILCOSEAL Cure and Bondbreaker have also been shown to provide excellent resistance to the “Osmotic Effect”. Silicate based sealers react with hydrated lime within the casting slab to help densify, harden, and reduce the porosity of the casting slab surface. The application of DURO-NOX to the casting slab surface immediately following joint saw cutting, followed by an application of SILCOSEAL Cure and Bondbreaker effectively cures and seals the casting slab surface thereby reducing the opportunity for osmosis to occur. With very porous casting slabs, successive applications of SILCOSEAL Cure and Bondbreaker may not be adequate to form sufficient surface holdout. In this instance, the casting slab surface should be saturated with water with the excess water squeegeed off immediately prior to a reapplication of the bondbreaker. In summary, to prevent the “Osmotic Effect” and the resulting incomplete hydration caused by water migration into the casting slab, it is necessary to stop the diffusion of water though the bondbreaker. This is best accomplished by saturating the casting slab with water prior to the placement of the panel concrete in conjunction with the application of a breathable chemically active cure and bondbreaker such as SILCOSEAL Cure and Bondbreaker.