spotted the first damp spot

16 years ago

We're currently building on a walkout basement. Poured concrete walls. About 50% of walls above grade. The walls were sprayed with "mastic" and covered with "shockwave" drain board. They also used an egg carton looking channel drain that pipes out to daylight.

The foundation was poured back in early February and we've kept a close eye for damp spots since.

This weekend we had a good soaking rain and we noticed a spot about the size of a pack of cigarettes that was damp. It was right where the wall meets the floor. The basement has otherwise not had a single sign of dampness.

How concerned should we be? would a dehumidifier keep this sort of stuff in check? should I not accept it and insist that they dig out the soil and re-apply all waterproofing?

Thanks.

Comments (4)

worthy
16 years ago
Hard call without seeing it. If your basement walls are still accessible--I guess they are or you wouldn't have noticed the damp spot--consider applying a crystalline waterproofing product such as Permaquik. This goes into the structure of the concrete and does not wash or flake off like other coatings.

I would also double check your grading and any way that water in a heavy storm might load up against the foundation.
jasper60103
16 years ago
I would bring it to the attention of the builder. I discovered a leak soon after my foundation was poured. They fixed it right away. That was 3 years ago and today I'm still enjoying a clean and dry basement.

just my .02
tragusa3
Original Author
16 years ago
Thanks for the input.

The interior of the walls are still exposed. The exterior has been backfilled. The grading is not final yet, and getting water away from the wall will be improved slightly.

I did call it to the builders attention. Haven't heard anything back yet.

Thanks again.
woodinvirginia
16 years ago
Building new addition now w/basement that was weatherproofed with GMX ULTRA and 2 inch Outside insulation board also.
Have noticed wet spots on heavy rains in corners. However I backfilled completely with gravel 4 foot away from all walls of my 44 by 20 ft addition. Builder says lack of gutters and lack of grading is contributing to moisture I see now. It will correct when those parts of the homebuilding are corrected.
Getting Danby 58 pint dehumidifier from Costco.com after reading reviews here & on Epinions.com. Seems that first year moisture from building materials etc. contribute to humid condition for 9 mos - 1 year. Danby 58 pint unit has drain connection & 5 yr warranty.