Masonry Technology FAQs
We hope the information here will be helpful. It is based on data and knowledge considered to be true and accurate and is offered for the users' consideration, investigation and verification, but we do not warrant the results to be obtained. Please read all statements, recommendations or suggestions in conjunction with our conditions of sale, which apply to all goods supplied by us. No statement, recommendation or suggestion is intended for any use which would infringe any patent or copyright. These products may be covered by patents, or patents pending. Grace Construction Products, W. R. Grace & Co. — Conn., 62 Whittemore Avenue, Cambridge, MA 02140. In Canada, Grace Canada, Inc., 294 Clements Road West, Ajax, Ontario, Canada L1S 3C6.
I specified DRY-BLOCK in the concrete masonry units and mortar. Is this all that is needed to prevent water from entering my building?
When properly designed, single-wythe concrete masonry construction provides the performance of cavity wall construction, but in a more cost-effective manner. Proper design means the drainage wall concepts of protection, collection, backup and drainage should be incorporated in all single-wythe masonry construction. The use of the DRY-BLOCK® System provides protection by forming an effective barrier to the intrusion of water into the wall. Likewise, it provides an effective backup by virtually eliminating the wicking of water into the masonry so that any water that may enter the wall system will readily fall down the cores and exit at the flashing weeps. It assures that water will not wick into the interior of the building.
However, for single-wythe concrete masonry construction to provide superior performance it takes more than just using DRY-BLOCK®. The walls also need to incorporate collection and drainage. Proper flashing and weeps must be incorporated in the design along with movement joints designed and located appropriately to control cracking. Finally, it is also important the mason contractor follow good construction practices and install each component according to the design specifications and drawings.
Can masonry treated with DRY-BLOCK be painted?
In general, if the paint can be applied to non-DRY-BLOCK masonry, then it can be applied to DRY-BLOCK masonry. Paints that have been successfully used with DRY-BLOCK include latex, acrylic latex, waterborne epoxies and cementitious based coatings. Oil based paints (alkyl paint) are not recommended for most masonry construction, especially in exterior applications. For additional information please see Technical Bulletin 14 "Compatibility of Post Applied Coatings and DRY-BLOCK.
Can masonry treated with DRY-BLOCK be sealed with a post-applied water repellent?
When a clear penetrating sealer is desired for additional protection, INFINISEAL® DB, manufactured by W.R. Grace & Co is recommended. INFINISEAL DB is a quality silane and siloxane based water-repellent sealer which has been formulated and thoroughly tested to ensure optimum performance with DRY-BLOCK structures. For additional information please see Technical Bulletin 14 "Compatibility of Post Applied Coatings and DRY-BLOCK".
What is the life expectancy of DRY-BLOCK in masonry?
DRY-BLOCK has provided water repellent properties to masonry for 25 years, and is designed to perform for the life of the structure.
Is masonry treated with DRY-BLOCK breathable?
DRY-BLOCK is a liquid polymeric water-repellent admixture that is mixed throughout the concrete during manufacture of the concrete masonry unit and mixing process of the mortar. It "coats" the masonry pores but does not block them. DRY-BLOCK does not form an "impervious film". Masonry treated with DRY-BLOCK remains breathable and will not act as a vapor barrier.
I often see asphaltic coatings specified as damproofing on the back up wythe in cavity wall construction. Can DRY-BLOCK be used as an alternative in this type of application?
DRY-BLOCK is a very effective alternative to asphaltic coatings for damproofing the back up wythe in cavity construction. By being integral throughout the whole CMU and mortar it is more effective than just surface applied asphaltic coatings.
Can DRY-BLOCK Block and Mortar Admixtures be used interchangeably?
Due to the physical differences and the methods of manufacture between concrete masonry units and mortar DRY-BLOCK Block and Mortar Admixtures cannot be used interchangeably. DRY-BLOCK Block Admixture contains special plasticizers to improve the machinability of CMU while DRY-BLOCK Mortar Admixture contains additives to improve the workability of the mortar and increase the bond between the mortar and the CMU.
What happens if either DRY-BLOCK Block or Mortar Admixtures freeze?
If DRY-BLOCK Block or Mortar Admixtures go through a freeze-thaw cycle then the product will separate and be unusable.
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INFINISEAL® DB Questions
How does this sealer differ from others already commercially available?
Specially formulated and tested for compatible water repellency performance with DRY-BLOCK walls, INFINISEAL® DB is a unique water-based silane/siloxane that provides maximum water repellency protection without any negative effects on DB walls.
Being water based it does not have the detrimental environmental effects associated with solvent based sealers.
Being specially formulated for DRY-BLOCK walls it has an optimum blend of silanes, siloxanes and emulsifiers to assure excellent penetration and performance. This is not necessarily the case when other water based sealers are used on DRY-BLOCK walls.
What effect will INFINISEAL DB Sealer have on the appearance and color of the wall?
Laboratory tests and actual field conditions indicate that INFINISEAL DB Sealer has very little if any effect on the color and appearance of the wall. Accelerated aging studies also indicate that there is very little color change after extended exposure to UV light.
While our experience indicates that change in appearance should not be an issue, it is recommended that a test panel be used to confirm the appearance of the sealed wall before the project is started.
When applying the sealer, if the whole job cannot be finished in one day then it is best to make the sections start and end at natural breaks in the structure and not in the middle of a large wall — just as one would do with any other coating or painting operation.
How long will INFINISEAL DB last? How long until you need to reseal a building?
Because INFINISEAL DB Sealer actually chemically reacts within the penetrating area of the cementitious portion of DRY-BLOCK Block and Mortar, it can provide surface water repellency for 5 - 10 years or more.
The life span of the sealer application depends on the condition of the CMU and mortar joint areas and on the effect of building exposure and proper maintenance on the masonry. Resealing is typically recommended every 5 to 10 years or when needed
If DRY-BLOCK Admixtures make the CMU and Mortar water repellent, how can INFINISEAL DB penetrate since it is water-based?
The active materials in INFINISEAL DB Sealer are actually oil soluble and are suspended in the water-base as an emulsion. This allows the active materials to penetrate and react within the CMU matrix. Also, the surfactants used in the emulsification process during manufacturing assist in properly wetting out the DRY-BLOCK surface allowing for proper sealer penetration. This is what separates INFINISEAL DB Sealer from some other water-based sealers. Lab tests indicate that some of these other sealers do not penetrate as well and are not nearly as effective as INFINISEAL DB Sealer.
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Mortar Admixture Questions
Is MORSET® an anti-freeze mortar admixture?
MORSET is a set accelerator that speeds the hydration process therefore reducing the setting time and increasing early strengths. MORSET will not prevent plastic mortar from freezing.
Is MORSET compatible with DRY-BLOCK® or DRY-BRICK™ Mortar Admixtures?
MORSET is compatible with both DRY-BLOCK and DRY-BRICK Mortar Admixtures when added to the mix separately.
When using MORSET, are standard cold weather construction practices still necessary?
Yes. MORSET will accelerate the hydration process and increase early strengths. MORSET will not prevent plastic mortar from freezing. It is strongly recommended that the guidelines offered by the National Concrete Masonry Association, the All-Weather Council and ACI 530.1 Specification for Masonry Structures be followed.
Can MORTARD®-E be used in on-site produced mortar?
MORTARD-E is designed and recommended to be only used in batch plant prepared mortar to produce extended life mortar.
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Multi-Purpose Efflorescence Controllers Questions
Will RX-901™ control secondary efflorescence?
RX-901 is designed to control primary efflorescence. However, some limited secondary efflorescence may also be controlled.
Will CONTROL™ reduce primary efflorescence?
CONTROL is designed to reduce secondary efflorescence and not primary efflorescence.