Building Homes or Extensions/anchor bolts retrofitting


we had a home inspection where it turned out mud sill straps were used instead of anchor bolts to secure the foundation plates/sills to the foundation.   I consulted a structural engineer with the question the house has been there 13 years is this issue just a code issue or a real life problem.  He felt yes its been there 13 years but what was done was not right and i probably should post install anchors.  He said the material costs was about $30 each and code required this every 6 feet   He said it required drilling two holes (I assume one through the concrete and one through the wood sill??)
The engineer said he didn't know what the labor costs might be to post install anchors   The crawl space is about 3' and one can kneel in it but not stand.  Any really rough idea what costs might be to post install anchors per anchor in a crawl as were in our inspection/option period and trying to get a handle on rough costs.


Rod, this one is hard to answer.

The main problem I am seeing is being able to drill the holes.  If the joists are 2x12's, you have an 11 1/2 in height to work in.  I don't own anything that can stand up in that space other than a right angle drill which is not hammer capable which would make drilling down into the stem wall quite a chore.  You've already worked with a structural engineer, ask him how you would/could do this.  He may be able to show a design that can be used where drilling into the foundation or stem would be doable.

One of the main suppliers of the newer hold down devices and seismic and wind load developers is Simpson Strong tie.  Take a few pictures of the situation and give their technical department a call.  They may be able to fix you right up:

I tend to take some things discovered by home inspectors with a grain of salt.  The house has been there through whatever weather has occurred with no apparent problems.  It must have passed some form of code inspection when it was built unless it is not in a municipality with an AHJ.  Only you can decide how big an issue this is.  

Building Homes or Extensions

All Answers

Answers by Expert:

Ask Experts


Dan Griffin


I can answer almost all questions related to the total construction process. My expertise is in commercial construction, though I can field most any residential question. I have hands on experience in concrete, heavy equipment, masonry, all phases of carpentry, interior finishes, and I am fairly strong in mechanical and electrical.


I have over 20 years experience as a commercial carpenter and commercial construction superintendent. I have another 20 years experience in facility management for a major school district.

My favorite hobby for he past 12 years has been singing bass in a The OkChorale men's barbershop chorus and the Mature Moments quartet.

I hold a Bachelor's degree in English and Math. I have completed many continuing education hours in the building trades. I hold a Master Carpenter card from the AGC, Associated General Contractors.

©2017 All rights reserved.