Waterproofing Products for Exterior Basement Wall
I’m planning to construct a 24’x32′ building with a “walkout” style basement. I live in middle TN (CZ 4A). I appreciate the information available on this website; I’ve learned a lot. The foundation wall will be poured concrete and I’d like to waterproof the exterior side of the wall before backfilling so that the basement interior stays nice and dry. From what I’ve gathered, waterproofing consists of: roll-on/spray-on liquid membrane (or a peel-and-stick membrane), a dimple board to prevent hydrostatic pressure from accumulating against the foundation wall and a drain pipe surrounded by clean, crushed gravel and geotextile fabric at the footer. (Also, I plan on insulating the interior of the foundation wall with 2″ rigid foam.) Controlling surface water and roof run-off is extremely important too.
I’ve spent time searching the “world-wide-interweb” for waterproofing products. I’d prefer a roll-on product instead of a spray-on product (so I don’t have to get the spray equipment) but I’m not opposed to a peel-and-stick product either. Here are some products I’ve found:
1) Poly-wall Home Stretch Liquid Waterproofing (about $358 for 5 gallon).
2) Sikalastic -320 NS (about $220 for 5 gallon)
3) wrmeadows Mel-Rol LM (about $168 for 5 gallon)
4) Tremco Tremproof 201 or Tremproof 260 or Tremproof 250GC (about $225-$250 for 5 gallon)
5) Henry Blueskin WP 200 (peel-and-stick) (about $195 per roll)
I’m sure there are several other products out there. Does anyone have specific recommendations for a reliable, durable product that’s easy to apply for a DIYer? I’d love to hear from someone with hands-on experience.
Looking forward to the replies. Thank you very much.
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Replies
I installed a peel and stick from GCP called Bituthene 3000. Similar to the Ice and Water that they make. You purchase a primer to go with it. The primer gets rolled on and helps tremendously for the peel and stick membrane to stick to the concrete wall. I have some spots where I didn’t put primer and the sheet will peel right off.
I used this on my own home that I am currently building. It was very DIY friendly. My brother in law used the roll on waterproofing from WR Meadows on his house. The roll on product was messier to deal with, and it was harder to get the correct thickness.
If I had to do this again I would do the peel and stick again. I purchased mine from https://www.emisupply.com/. No affiliation with them.
Another thought for you. Instead of doing a dimple board you could put your exterior insulation on the exterior up against the foundation. You do have to figure out how to deal with the transition where framing starts, but something else for you to consider.
If you are DIY, peel and stick all the way. Bit more cost but you end up with a water tight foundation. As Dennis said, primer is the key for these.
Around me the box store stocks grooved EPS. These have channels to allow for water flow and can serve dual duty as insulation and drain board. This way you don't need rigid insulation on the inside of the wall so you are not adding any extra cost. It does need to be parged in the above grade section though. If your stores don't have it, grooved EPS is also commonly used for EIFS installs, the local supplier should carry it.
I also used bituthene as it was easy and gave a dependable thickness. I put XPS insulation board over the bituthene and was careful with keeping stones out of the backfill. We don't termite problems here
The Henry and WR Meadows peel and stick are essentially the same. They're easy to install once you get the hang of not letting it touch itself. If it does it's basically stuck forever, and need to be cut off, kind of aggravating in that sense.
The peel and sticks are cheaper than the fluid applied. There's really no justification for their tremendous premium, for residential construction, in my opinion. Not to mention you can complete the work over several different periods with the peel and stick and feel confident that everything is bonded together well.
Another vote for insulation on the exterior. You've got one shot to do it, and might as well do it now. It'll protect the whole structure that way. the dimple mat can attach directly over the XPS and you'll have a detail that's absent on 95% of modern homes.
Get a few bids I do not think there is any money to be saved buying perineum products like the peal and stick plus your time.
The way I see it the spray applied products are superior in that there are no joint and seams to leak.
The most important factor is a proper drain leading to daylight.
Walta
Thanks for the replies everyone.
I'm surprised that peel-and-stick membranes are easier to apply than a roll-on membrane for foundation waterproofing. It seems similar to the argument for liquid flashing vs tape to seal window rough openings. The liquid flashing supposedly eliminates the tape origami required in some situations. Just slather the liquid flashing to the proper thickness and you're good.
But I'm not against a peel-and-stick product for the foundation walls. I can see the benefit of a guaranteed, consistent thickness. If most people recommend peel-and-stick, I can do that.
I compared the data sheets for the Henry Blueskin WP200 to the Bituthene 3000 and they are almost identical. The data sheet doesn't give the actual chemical composition (that's probably proprietary) but they meet the exact same testing standards. As someone noted in a previous comment, they are essentially the same.
I appreciate the comments for exterior rigid foam insulation but I haven't convinced myself that's the way to go yet. I'm very concerned that termites, ants, bugs, even moles (my yard has a healthy population) would have a field day with exterior foam. Since this is a walk-out style basement, a lot of the foundation (and foam) will be above ground. It's not just a 6"-8" strip around the bottom. That above ground foam has to be covered and protected. I haven't found a great solution to that problem on this forum either.
Unless someone has a compelling argument, I'll likely stick to rigid foam on the interior side.
I do appreciate everyone's comments though.
If anyone has a great video on peel-and-stick installation, I'd love to see it. I'm looking at the manufacturers installation instructions now, but I haven't run across a good video from an independent person. Doesn't look like rocket surgery but there are a few steps involved (clean all the surfaces well, apply a large fillet at the footer to wall joint, apply a primer the wall, apply a 12" of material strip to the outside footer corner, apply the peel-and-stick membrane, seal the edges or use termination bars). A video of the procedure would be nice...
I applied a fillet to the bottom of foundation wall using some fast setting cement. I started used a product from GCP in place of the fillet but gave up as it was hard to work with.
I did use a Diamond wheel on a grinder to grind down all the seams created from the panels. I didn’t want the membrane to be punctured. I didn’t do anything crazy to clean the surface other than using a battery powered leaf blower to clean it off.
Bluegoose,
I think everyone's (including mine) recommendation for the peel and stick is due to the cost. At the same price I'd choose the fluid applied, but I believe the P&S can give equivalent performance, which is why I always recommend it, even if it's a little more labor intensive.
Here's a few to get started:
https://youtu.be/JmVTDrkA3Bk?t=60
This channel on YT is great, and I wish it had more views.
https://youtu.be/lCHI50gTLr8
There are plenty of others, but it looks like you've got the right idea, and those are essentially all the right steps. I don't think the termination bar is really necessary if you've got a clean, primed surface, and use a bead of the recommended sealant across the top edge.
bluegoose,
could u share what u ended up using?
I'm building our house right now with a conditioned (unvented) crawl space. I needed to waterproof and read through this thread. Because of the clips and seams in my concrete, I opted for a liquid product and had a wonderful experience.
I bought Multicoat BG-2000, cleaned my foundation with TSP sprayed out of my backback sprayer (guys used an oil-based form release, if they'd used water-based I could've skipped this step), then pressure washed, then rented a big Graco airless from HD and bought a 621 tip (0.021 oriface)... I marked off 200 sqft sections and made sure I sprayed a whole 5 gallon pail on each section before moving on. Was fun, I'd definitely recommend it. I paid $225/bucket for the BG-2000 from my local White Cap Supply.
Tried to post a photo but it's erroring. Sorry. Looks beautiful and feels great.