Choosing a brush/roll on foundation water proofer?
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Hello,
I will be breaking ground on a new house in the next few months. One of the last details I have left to figure out is choosing a brush/roll on foundation waterproofer. The house is a 30′ x 60′ one story rectangle. Part of the house will be slab (music studio) the rest will be sealed crawl space. It will all be on a 12″x24″ continuous footer with 8″ block on top. The slab will be poured inside the block wall perimeter. (not a mono slab) The site is about a 5% grade on a hill top with some exposed rock. I anticipate getting to bedrock with the footer on the high side. I will be installing a foundation drain system all the way around per the specs on this site. I will also be sure to have the site graded properly and run my gutter water away from the house. I have decided on a roll/brush on waterproofer as the final part of the system, but I am having a hard time choosing a product. In doing research I think a polymer-modified water-based asphalt material will be best for my needs, but i am open to suggestions. Does anyone have any recommendations or experience with such a product? Brand / supplier? Obviously I want to get this right the first time. 🙂 I am also all ears on any other advice on the subject.
Thanks in advance for any and all of your help.
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Replies
Spray on the asphalt emulsion sealer. It's faster and gets into irregularities in the concrete much better than a roller or brush.
One caution on the water-based asphalt coatings: We had it sprayed on during a bit of wacky weather--a week of cold (just above freezing) followed by a very warm, humid day, when it was sprayed on. What happens to cold concrete on a warm humid day? Condensation. So instead of the coating drying, it get wetter and sloughed off. Then it rained and made a mess. So make sure you have weather conditions that promise the dew point will be lower than the temperature of the concrete for ~24 hours after or rolling on the coating.
Joe,
Spray-on or brush-on coatings for foundations are considered to be dampproofing, not waterproofing. If you have good footing drains and backfill with granular, free-draining material, these coatings work fine (especially for a crawl space foundation).
If you were building a basement (especially one that might be finished some day), you would probably want to graduate from a dampproofing system to a waterproofing system.