Concrete foundation

indep · 10-14-2008, 04:08 PM

Hi,
I recently purchased a new home that is being constructed and over the weekend I went and saw the finished concrete foundation. On one side of it, there is a line about 5 feet long and 2 inches wide where the concrete is not solid, it looks porous, sort of like the inside of an aero chocolate if you know what i mean, it's not a crack it's as if there were air bubbles inside or something. I contacted the builder and he said he will look into it. I wanted to ask you guys if they can fix this easily and will it not affect the life of the house, and what methods can I use to check the rest of the foundation to make sure that the concrete is solid.

any help will be greatly appreciated

HandyPete · 10-14-2008, 04:18 PM

STOP! don't do anything with that crack...it's the contractors job. Call the inspector out and have him give you advice. If that fails call an architect or a civil engineer.

_pete

oh...and don't pay that bill until you get the right answer from a third party.

**Termite** · 10-14-2008, 04:33 PM

Could be two things...

1) It could be an air pocket where they failed to adequately vibrate/consolidate the concrete when it was placed. Although not ideal, this is usually not a real big deal unless the voids are significant. Small scale air pockets happen. If it is a few feet long or very deep I'd ask for engineering.

2) It could be a cold joint, or differential pour. If the concrete toward the bottom of the wall is allowed to set up somewhat before the entire height of the wall is placed, it is called a cold joint. It often happens while they wait on concrete or get delayed working on the other side of the house. Cold joints are usually identifiable by slight variations in color, and they're usually somewhat horizontally oriented or somewhat sloped. Whether or not it is a problem depends on a lot of factors. Wet concrete does not bond well to set concrete, so it is a weak point. It it is a cold joint, I would ask that the builder and concrete contractor provide an engineer's report (stamped) either ok'ing or recommending repairs. As an inspector, when I see a cold joint, that's what I require.

concretemasonry · 10-14-2008, 06:45 PM

Run it past the inspector since he working for you since you have a permit for the house.

The strength of a footing that a wall is bearing on is of little consequence since many foundation wall systems (wood and precast) do not require a concrete foundation. A footing is mainly meant to spread out the loads if you have really bad soil or to provide a good base to work of off if you have poured or block foundation walls.

You may be looking at "honetcombed" ot poorly consolidated conrete that is still much stronger than the soil under it.

Let your "employee" (the inspector to judge if it is acceptable since the contractor will have to answer to him if there is another job.

indep · 10-21-2008, 12:37 PM

Sounds good, Thanks guys.
I talked to the site supervisor and he told me it's an air pocket and they will fix it when they do the parging

**Termite** · 10-21-2008, 02:07 PM

Quote:

Originally Posted by indep

I talked to the site supervisor and he told me it's an air pocket and they will fix it when they do the parging

You didn't take the advice we gave you then. Of course he told you it is an air pocket...That's the only thing it can be that won't cost him any money to fix.