Messages and Online Forum Q&A

Re: Tying new foundation to old

From: info@builderswebsource.com
Category: Concrete
Remote Name: 63.198.181.43
Date: 05 Nov 2001
Time: 08:33 PM

Comments

While every situation is different, generally new foundations are anchored to existing foundations by drilling holes into the existing foundation, and inserting horizontal #4 dowels or rebar which tie into the new foundation. You can also use an epoxy, such as Simpson's or similar, to anchor the rebar tightly into the old foundation. The dowels help to prevent lateral movement of the new foundation relative to the existing foundation. Reinforcement itself is provided by proper use of rebar. If you use epoxy, be sure to clean out the hole with compressed air, otherwise the epoxy will not bond well to a hole filled with concrete dust. You'll need a hammerdrill with a concrete drill bit to bore out 4-5" deep holes in the existing foundation.

Make sure that any rebar overlaps at least 24 inches or according to code, whichever is more stringent.

Builders Websource

Article Tools

Builders Websource® is a corporate member of ASTM International—a non-profit engineering body dedicated in part to the standardization of building materials specifications, products, systems, and test methods for improved health, safety, and reliability of residential and commercial structures.

Copyright © 1999 - 2008 Builders Websource®, an InBuild™ company. All rights reserved.