Why Tom Silva Has No Clue How to Waterproof a Basement
At the beginning of the year, we started a basement waterproofing blog called “Basement Matters”. Our main goal behind the blog was to educate homeowners by publishing fresh and original articles and videos drawing from our 55 years of experience. As a part of the project, I examined hundreds of industry-related websites. Most of what I found was rather uninspiring to say the least.
When looking for information online, one of the more common searches used by homeowners on Google is “how to waterproof a basement”. I was shocked to see what currently shows up in the number one spot. Below is link to the video on You Tube. It’s just a couple minutes long. Watch it and then let’s resume our discussion.
CHECK OUT “THIS OLD HOUSE” VIDEO ON HOW TO WATERPROOF A BASEMENT
In the video, General Contractor Tom Silva lays out 6 steps to waterproof a basement. Let’s examine them one at a time:
1. Fill cracks and holes in concrete walls and floors with hydraulic cement
2. Apply a coat of waterproof masonry paint to inside surface of basement walls.
3. Attach flexible extensions to ends of downspouts to carry water away from foundation.
4. Dig trench directly below downspout for 4‑inch-diameter PVC pipe.
5. Connect downspout to PVC pipe.
6. Install a drywell at opposite end of pipe to catch and disperse rainwater.
I’m not entirely sure where Mr. Silva got his information from, but I can assure you that it wasn’t from an experienced basement waterproofing professional. Filling cracks and holes with hydraulic cement or applying masonry paint to your interior basement walls are horrible ideas. This video should really be renamed “How NOT to Waterproof a Basement!”
So what’s wrong with this process? Well, for starters, hydraulic cement (step #1) is nothing more than a surface patch. It’s not something a professional waterproofing contractor would ever consider using as a permanent repair or for anything other than patching a small hole in the foundation wall. Hydraulic cement also has no strength and cracks easily.
Applying a coat of waterproof masonry paint (step #2) is another terrible idea. Why? Well, your foundation wall is, on average, 8 to 12 inches thick. Putting a coat of paint on the interior surface of the wall is not going to prevent the water from traveling all the way through the wall. At best, it is a short term solution that might help with minor water and vapor transmission.
I’m actually going to give Mr. Silva credit for steps 3 through 6. Extending your downspouts so that the hundreds of gallons of water from your roof are deposited as far away from your foundation as possible is a great idea. Had he only included those steps, I wouldn’t have written this article.
Bottom line: just because you find something online doesn’t mean you should treat it as gospel. Anyone can write anything they want on the World Wide Web. It doesn’t make them an expert.
I try not to boast or brag with these blogs. The fact is we have waterproofed over 300,000 basements over the past 55 years. We just stick to basement waterproofing. With all due respect, Mr. Silva should just stick to general contracting.