Not so dry Tuff N Dri
The concrete sub sprayed my poured basement wall a week ago, slapped on tremco warm n dri board, drain tile and laid 18 inches of gravel in the same day. Has been raining some every day since and still not dry in spots. The brick ledge has washed off some as you can see streaks of the liquid asphalt here and there soaked through the fiberglass barrier board. Have trench footing so there has been standing water and concerned about the exterior wall footing joint. I cannot imagine the tuff and dri cured correctly down there. Contractor is saying it will be fine when it dries but it has been over a week and the curing time is supposed to be 24 hours. 1 local guy said they should remove the gravel, the drain, the board, everything and scrape soft spots and respray. Contractor resisting. Any thoughts?
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Martin,
Your question is a little cryptic. When you wrote, "the concrete sub sprayed my poured basement wall a week ago," I wasn't sure what was being sprayed -- spray foam insulation or dampproofing? -- or where the substance was being sprayed -- on the interior or the exterior of the wall?
It turns out from my Googling research that Tuff-N-Dri is a basement waterproofing system. OK, I'm getting closer to deciphering your question.
Here is a link to the Tuff-N-Dri installation instructions. If you read them, you may be able to determine if your contractor followed the instructions. Concerning the brick ledge, note this disclaimer: "The TUFF-N-DRI System Limited Warranty covers neither the horizontal surface of the brick ledge nor the vertical wall surface above the ledge regardless of wall type."
Thank you Mr Holladay. My concern is the seam where the footing and wall meet on the exterior. As I understand, this is a primary place to seal, which makes sense, particularly for a trench footing that is level with the ground. The instructions for the waterproofing just says respray as needed. My question is as follows --- if the liquid membrane has been in water or moist at the footing for a week and is still not cured, can it still bond and be effective? There is no way to know on this end without removing the gravel and drain which is covering it up. Some parts of the wall membrane, especially ledges are still soft.
Martin,
I suggest that you direct your questions to a technical representative at Tremco. Here is the phone number:
Tremco Barrier Solutions
800-876-5624
Tremco says it is hard to say and to talk to contractor. I guess I am in what you call "Catch 22."
Martin Luther,
Can you describe a trench foundation. Is it one where the footing was poured without a form?
Yes, footing is poured into dug out trench, hard soil. No form used, which means the tuff n dri was sitting in water for a number of days which prevented curing during the expected 24 hr cure. Other horizontal places so wet in spots that membrane is like oil on fingertips.
This sort of begs the question: Why was it sitting in water at all? if the footing drains were properly installed, they should be taking the water out of the footings. Do they drain to daylight, or will you be using a sump pump to remove water from the footings?
Your drain pipes need to be below the level of the interior slab, and that usually means alongside the footing, not on top of them. This precludes trench footings, unless the soil is removed from the sides of the footings after they cure so that the stone and drains can be placed alongside.
perhaps a sketch of your foundation walls and waterproofing would help us understand your specific application.
That said, generically, if the manufacturer requires 24 hours of curing before exposure to water and that condition was not met, make the contractor redo it. Why should you assume the risk of failure purely to save the contractor time and money? it was the contractor's election to race the rain.
Drain pipe or drain material can and most often does set on top of the footing since the top of the footing is 4" below the top of the interior concrete slab. There is or should be a minimum of 4" of gravel under the slab. It has been my experience that almost all waterproofing leaks are due to clogged pipe on the footer. Homeowners should be made aware that it is their obligation to inspect both ends of the foundation perimeter drain pipes on a consistent basis, ( at least yearly). Do this and you most likely will never have water in your basement. Hydrostatic pressure builds up and always takes the path of least resistance.
I think you meant that the bottom of the slab should be 4" above the top of the footing, not the top.
Oops! My bad!!!
Thanks Peter for your helpful comments. Yes, the drain is to daylight but it was not finished to daylight yet as the pipes on each end were tied up to the anchor bolts - I guess to keep them out of the way. I think it is designed fairly well, good slope, etc, it is just that the membrane was not given time to cure in normal fashion. I tried to get them to put drain tile beside footing instead on top but they would not hear of it.
Martin Luther,
Unfortunately, as Peter said, having the perimeter drains on top of the footings means that vulnerable joint between the footings and foundation wall is frequently wet and susceptible to leaking. Trench drains should only be used when the soil has adequate drainage so that perimeter drains aren't needed, or the project is a slab on grade. Providing enough fill to bring the slab higher than the perimeter drains would be the best way to help alleviate the problem.
As to who is to blame. That's a tough one to call from a distance. Sounds like something your GC, who presumably was responsible for the perimeter drain system, and the concrete sub to work out.