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WATER ENTRY IN BUILDINGS
AGE of MOLD - Old is the Mold?
BASEMENT CEILING VAPOR BARRIER
BASEMENT MOLD WATER IMPACT
BRICK WALL DRAINAGE WEEP HOLES
BUCKLED FOUNDATIONS due to INSULATION?
BUILDING DAMAGE ASSESSMENT & REPAIR
CONDENSATION on WINDOWS & SKYLIGHTS
DEW POINT TABLE - CONDENSATION POINT GUIDE
EFFLORESCENCE, Salts & White / Brown Deposits
FLOOD DAMAGE ASSESSMENT, SAFETY & CLEANUP
FLOOD DAMAGED FOUNDATIONS
FLOOD VENTS & FLOOD PORTS
FLOODS IN BUILDINGS-mold
FLOOR DAMAGE DIAGNOSIS
FOOTING & FOUNDATION DRAINS
FOUNDATION BULGE or LEAN MEASUREMENTS
FOUNDATION CRACKS & DAMAGE GUIDE
FREEZE-PROOF A BUILDING
FROST HEAVES, FOUNDATION, SLAB
HUMIDITY LEVEL TARGET
ICE DAM PREVENTION
MOISTURE CONTROL in BUILDINGS
MOLD INFORMATION CENTER
NOISE / SOUND DIAGNOSIS & CURE
ODORS & SMELLS DIAGNOSIS & CURE
SEWAGE BACKUP, WHAT TO DO
SEWAGE BACKUP TEST & CLEANUP
SEWAGE BACKUP PREVENTION
SEWAGE PUMP CLOG DAMAGE
STAIN DIAGNOSIS on BUILDING EXTERIORS
STAIN DIAGNOSIS on BUILDING INTERIORS
SWEATING (CONDENSATION) on PIPES, TANKS
TOILETS, INSPECT, INSTALL, REPAIR
TRAPS on PLUMBING FIXTURES
VAPOR BARRIERS & CONDENSATION in BUILDINGS
VENTILATION in BUILDINGS
WATER ENTRY in BUILDINGS
WINTERIZE A BUILDING
Basement sealers to control moisture & water entry: this article discusses options for sealing basement or crawl space floors and walls, or other building foundation walls to stop water entry and to reduce interior moisture and mold risks. The photograph at page top shows a very wet basement foundation wall built of concrete block. The stain pattern extends high on the basement walls, down the full wall, onto the basement floor. Correcting this particular water entry problem should begin outside with roof drainage and surface runoff. This article discusses foundation wall and floor slab sealant options. .
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
Aaron Kuertz, Applied Technologies, Inc.
Using Exterior Foundation Coatings to Repair Foundation Wall Cracks & Leaks
As Carson Dunlop Associates' sketch shows, foundation crack leaks can be repaired from outside the foundation wall using a combination of asphalt-mopped d & roofing and a waterproof bituminous membrane that is then adhered to the wall surface.
Sodium Silicate Sealers for Floor & Foundation Wall Waterproofing
Sodium silicate is used in a water-based mixture to seal the basement walls and floors.
The sodium silicate penetrates up to 4” into the substrate.
After penetrating the sodium silicate reacts with the free lime content of the concrete or masonry . Concrete, concrete block and masonry has lime as a natural component in their composition.
This reaction between the sodium silicate and free lime produces a solid crystalline structure that fills the microscopic cracks and pores of the substrate. This hardens and densifies the concrete and masonry so that water vapor and gasses cannot migrate through by capillary action. Also, gasses are retarded from entering a basement. After curing, the substrate looks the same as if it were not sealed. There is no surface film or sheen to it.
Benefits of Sodium Silicate for Building Waterproofing
By sealing the basement walls and floors with sodium silicate water vapor will be stopped from entering into a basement. The basement will be dryer than before. This greatly improves the interior air quality of a home by retarding the growth of mold and mildew.
Since the surface of the walls and floors are hardened, they will have less dusting and chalking. Gas transmission will be reduced as well, further improving air quality.
Many people like to paint the floors and walls of their basements. If paint is applied to unsealed walls and floors, it is possible for the water vapor to get trapped under the paint. After a period of time the water vapor can break the bond between the paint and the substrate. This causes the paint to blister and peel.
After application of a sodium silicate the walls and floors can be painted without fear of the paint peeling and flaking. Also, adhesives for tiles or other floor coverings can be used.
Application of Sodium Silicate for Basement or Crawl Space Waterproofing
Sodium silicate is applied to bare concrete, concrete block or masonry. Anything that would prevent the sodium silicate from being absorbed must be removed. No grease, dirt, soil, adhesives, oil, sealer or paint can be on the surface to be sealed prior to application.
Application is done simply by using a garden sprayer, roller or brush. First dampen the surface with water using a mop or brush. Apply in areas 10’ x 10’ in several light coats. Apply each coat after 10-20 minutes. Concrete takes 2-3 coats, concrete block and masonry 3-4 coats. Do not over apply the sodium silicate since if all of the product is not absorbed it may leave a white residue. Wipe up any excess product.
For several days after application loose dirt will be pushed out of the substrate. This is normal and can be swept off.
A Few Caveats about Any Foundation Sealer or Weather Barrier Product - DF OPINION
Watch out: any surface coating, even a penetrating wall sealer such as discussed here, can fail if exposed to continued or chronic water and water pressure through the foundation wall.
The pressure from water, frost, or more significantly, the formation of efflorescent salts (see EFFLORESCENCE, Salts & White / Brown Deposits) can exert tremendous pressure, sufficient to separate a paint or other coating from a masonry foundation surface. Efflorescence has been cited in several paint failure studies where these forces were explored.
Some factors that affect the durability and thus success of any foundation coating or waterproofing coating include:
Watch out: sodium silicate is an alkaline substance that can cause burns, eye, and skin damage. Quoting from a MSDS:
Thanks to reader Stan Rosenbaum for alerting us to the need for care when working with sodium silicate.
Weather Barrier Coatings, Mastics, Sealants, Adhesives used on buildings, Building Sheathing & Building Foundation Coatings
AkroGuard, Omega Products, International, 1681 California Ave, Corona, CA 92881, Tel: 800-600-6634, 951-737-7447, Fax: 951-520-2594, Quoting from the company's product description:
Thanks to reader J. Campbell for pointing out this product, March 2010.
Krystol Hydrostop, Kryton Corporation, "Crystalline Waterproofing" masonry sealer. MSDS for Krystol Hydrostop WB [copy on file as /exterior/Krystol-hydrostop-wb.pdf ] - WB from Kryton Corporation. Masonry sealer.
Vi-Cryl CP-10 (Trowel Grade) & Vi-Cryl CP-11 (Spray/Brush) Weather Barrier Coatings, Childers Corporation. We discuss the use of this coating at INSULATION LOCATION for BASEMENT WALLS. Quoting from the company's product literature [copy on file as /exterior/Vi_Cryl_cp-10-11.pdf ] - ,
Also see INSULATION LOCATION for BASEMENT WALLS,
see WET BASEMENT PREVENTION for our complete list of basement dry-out or water entry prevention methods.
Frequently Asked Questions (FAQs) About paints, sealants, crack fillers used to seal leaky basements & crawl spaces
I have a leak in my basement what do I use to seal leak thank you. - R.Y. 12/12/2012
Before sealing a basement leak, it's important to identify the water source - else the leak will continue or will reappear nearby. Find and fix the cause.
With that step taken, depending on the leak point and building surfaces involved (which you haven't yet described) we can recommend some solutions. The choice of best sealant or coating depends in part on what kind of surface is to be sealed and second the nature of the moisture, dampness, or water entry trouble.
for complete guidance on finding, fixing, and preventing basement water entry. You might also want to take a look at
Questions & answers or comments about using sealers to waterproof basement walls - an attempt to control basement moisture & water entry leakage
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Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.