Construction Contractors Community

Contractor Florida · Joined: 17 Aug 2009 Posts: 86 Location: Florida

First, all residential foundations crack. Concrete has water as an ingredient in the mix. As the concrete cures, it goes through a chemical process that causes it to harden into a solid. As it hardens, the concrete actually loses volume; that is it shrinks. In fact a concrete wall 100' long can shrink by as much as ¾".

The shrinkage process causes stress forces to develop in the concrete and to relieve the pressure, it cracks. This is okay because a concrete foundation has steel reinforcing bars inside that maintain the strength of the foundation wall. It is common to see cracks develop in the middle of a long wall, under a window or where the foundation steps down.

You will notice that the cracks are usually wider at the top of the foundation and get narrower as you go down the wall. Again, this is normal. You should rarely see the reverse and if so, it may be signs of structural problems with the foundation.

Florida General Contractor

TopSC · Joined: 23 Mar 2010 Posts: 4 Location: USA

Great info on concrete curing, going to the next level in the job would require prepping the concrete surface for a commercial concrete coat to protect the surface.
Concrete Floor Coatings

keven lee · Joined: 26 May 2010 Posts: 10 Location: Skelmerdale

This is very nice article budy having all the concrete curing information, from a lomg time i was looking for this information. Thanks to share this valuable information.