Patching a hole in Foundation

by Mike Weber
(Hudson, Quebec)

Q. My house has a 10" poured concrete foundation. There is a small hole (8" x 12")in the foundation that was used as a vent into a cold storage room. The hole is about 12" below grade and had a wooden "snorkel" that poked above grade to allow fresh air to enter the cold storage room.

Needless to say the wood rotted and now I have water seeping through the hole.

I want to plug the hole with concrete. I've already dug to expose the hole and removed the vent snorkel. The concrete is clean and in good condition. I have a piece of 1/2" plywood bolted over the hole on the inside wall. I've built a small form for the outside wall that will allow me to pour concrete level with the top of the hole - not yet attached.

What type of concrete should I use to fill the hole - or is there some material other than concrete that I should use? I assume I should use a suitable glue to bond the fresh concrete to the old.

Will the concrete plug for a water tight seal? If not what should I use to seal the outside of the plug to prevent water penetration. The hole extends only about 12" below grade.

A. You have to use a hydraulic cement like Water Plug to patch the hole in your foundation if it is below grade. Hydraulic cement will not shrink like regular concrete does.

Click here to post comments

Join in and write your own page! It's easy to do. How? Simply click here to return to General Concrete Questions.

If you liked this, please share.  Thanks!

Subscribe to my monthly newsletter

Enter Your E-mail Address
Enter Your First Name (optional)

Don't worry — your e-mail address is totally secure.
I promise to use it only to send you The newsletter.

Search This Website

Custom Search

Language Translator

Site Sponsers

That's us Pumping a slab!