Building Homes or Extensions/anchor bolts


QUESTION: we had a home inspection on a 2400 sq ft 1 and 1/2 story home with crawl that found that mud sill straps were used instead of anchor bolts to secure the foundation plates/sills to the foundation.   I sent the pictures of these to a PE with the question that the house has been there for 13 years and were these more of a code violation or a real life problem.  His response was that he felt it should be corrected and that the material costs would be about $25 to $30 with one every 6 feet of perimeter.   He said it would involve drilling two holes one through the concrete blocks but he had no idea what a contractor would charge to install each one.  Would you have any idea of rough costs to post install anchors in a crawl per anchor for labor (the crawl space is about 3' tall enough to kneel in but not stand in0 as we are in our inspection/option period and trying to get a rough handle on costs.

ANSWER: Hi rod, first of all, who said the straps were not acceptable?  Simpson strong tie has been making mudsill straps for years and to my knowledge still make them.  If they are installed properly and at intervals of 2-4' I don't see the issue here.

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QUESTION: Bruce:   Thanks for the prompt and informative reply!   I did have a follow up.  The home inspectors report said mud sill straps were used in lieu of anchor bolts and was the one that said it was unacceptable as when I called him he said this was a no no structural wise to use these instead of anchor bolts BUT he is a home inspector and not a general contractor.  So it sounds like the straps are fine.   That does raise the second question in that he had down the straps were not installed PMI (per manufactures instructions) and I have enclosed his pictures of same.  The PE I consulted  with the question of was this a big deal and could i just have a general contractor just bolt the straps down (or do whatever) was local (Charlotte ,NC) and knew the house was local so said he couldn't address that as it wasn't code and code here calls for anchor straps every 6' so I would need to post install anchor bolts.   I can see his answer as he probably can't come out and suggest a non code solution
So basically looking at the straps would you recommend that I get a contractor to attach the existing straps "PMI" and/or do I really need the anchor bolts.   I admit i am a dumb layman but I figure that 13 years ago when Ryan Builders built the house in Charlotte there was probably some code check and the straps were approved?   bottom line if it is truly a structural issue then I'll do whatever is needed but if its just a code when built is not code now issue then I'll pass

Hi again Rod, it looks like whoever did your mud sill attachment used strap anchors for a 2x6 mud sill instead of a 2x8..that being said, as you mentioned , these anchors were inspected by somebody from the building department and passed.  The purpose of a mud sill is to give your floor system a positive attachment to the foundation, however, there is no mention as to how the rest of the structure is tied together.  Here in Florida we have to have a positive connection from the roof trusses all the way to the foundation by means of truss straps, stud wall clips, and straps from the wall studs to the mud sill.  In many cases we bypass the mud sill and attach the floor system or the wall studs directly to the foundation using straps that are either poured into the foundation bond beam or run flat from the face of the wall stud past the floor system and then tap conned into the foundation or shot onto the foundation using power actuated pins.  So if the issue in your case is uplift requirements not being met at the floor system level, an easier alternative to trying to get anchor bolts installed is to use Simpson twist  straps inside the foundation wall and tying the floor joists directly to the foundation.  You can either tie each joist or every third or fourth joist depending on actual uplift requirements for your area.  These straps are nailed to the joist and then shot to the foundation wall with Hilti pins.   But as I mentioned above, if  your entire system is not tied together from the roof down, messing with your mudsill is a moot point. Sincerely, Bruce Johnson,

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Bruce E. Johnson


I can answer any construction related question in regards to carpentry, concrete, drywall, masonry, structural elements of any type of building, residential or commercial. Interior or exterior.


Custom Commercial and residential buildings. Churches, theaters, schools and auditoriums. Most recently I am working with the Catholic Church on several design build committees. I have a website related to scheduling and project supervision. Although my expertise is more related to multimillion dollar commercial, educational and theatrical projects my generous credentials in residential and remodelling construction make me a viable source of information regarding all forms of building questions.

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