Our new house is under construction, we are excited. But I am now concerened about the basement.

1. The hole was dug and footings poured.



2. The gravel was poured.



3. The walls were poured and exterior waterproofing sprayed on.



We had heavy rains over the past couple of days. Our basement retained the water. Our neighbors basement did not. Neither basement has any drainage system at this point nor sump pits installed.

Our basement:



Our neighbors basement:



Is this a good or bad sign that our basement retained water like this?

Thank you in advance for any advice.

Hard to tell, but you WILL notice that your neighbor's basement has no dampproofing on the outside of the walls, and yours does.

However, it depends on the amount of water. If all that's in your basement is what rained in there, that's one thing, but if more water than that came in, then there's a problem.

NOW is the time to ask your builder to apply another coat of dampproofing, and to embed a sheet of 6-mil polyethylene film in the wet dampproofing, extending down over the top of the footing. Then ask him to backfill with pea gravel, NOT the soil that was excavated.

Since the floor is not poured yet, have him install a sump pit, and be sure there is at least a 4-inch bed of gravel and a vapor retarder beneath your floor.

Thank you for the response. Interesting, I take it that you are hinting at the damproofing being the POTENTIAL culprit in that the water that accumulated in their due to the rain is being held in BECAUSE the damproofing is on the outside preventing it from draining unlike the neighbors whom just have not had it applied yet. I could live with that; it would mean that it is working and sealing the water inside which is in essence a good sign. Ideally, in the end we want it to work in reverse and seal the water out.

The water that is in there is only from the rain and nothing more. The blueprints call for 6-mil poly and a battery backup sump in addition to a floor drain and vapor retarder. I presumed that they would back fill with pea gravel as this is the correct way to do this. Everything else they have planned is appropriate but for safety sake, I will confirm the pea gravel and I am keeping a close eye on the project!

My only reservation is that a concrete foundation is not so porous as to allow rain water to flow OUT of it so quickly. There may be other differences in the soil under the two houses, or some other factor, that allows one foundation to retain water while another nearby foundation does not.

It's just that I did notice the dampproofing ON yours and NOT on the other.