Attaching sill to foundation

How are you attacing the sill to the foundation?
I'm planning to use presuretreated 2x12 on the foundation but will need to anchor the sills to the PT subsill. Thanks in advance!

Dan

Dan,
Is there a question in there somewhere ?
don't forget the closed cell air stop between the foundation and the 2x12.
deralte

Here's one way.....

I tied my stub tennoned posts to my timber sills with straps like those Jim has illustrated. The sills sit on a 2x12 PT subsill and are tied to the foundation with long J bolts.
In the addition where I was working with 2x8 floor framing and just the 2x12 PT sill I rabbeted my post bottoms to fit around the rim joist and used a lag bolt to tie them together.



I'm afraid my picture isn't as informative as Jim's but you can just see the rabbets at the bottom of the post.

For true "hold down" capacity with metal straps typically they should run up the post 2 to 3 feet (it depends on the calculated uplift based on exposure, roof size, and post spacing). Also every hole should be secured with 16 penny nails. But here's the real kicker, the strap should really be embedded in the concrete with a hook in the bottom, preferably looped around a piece of horizontal rebar. The simpson HPAHD22 (see link below) w/ 21-16d nails will give you between 4000 and 5000 pounds of uplift resistance. The strap around the p.t. sill is not considered adequate. That said, it is usually acceptable to most building inspectors to simply toenail the rim joist of a conventionally framed buildign to the sill...so go figure!

http://www.strongtie.com/products/connectors/PA-PAHD-HPAHD.html#gallery

Thanks Everyone! Yes, Emmett, there was a question in there. )) I was wondering what Simpson strong ties to use as well as other thoughts on securing the sill to the PT 2x12. The wind can whip around pretty good in the winter and I want to make sure things stay in place.

Thanks again!
Dan

Emmett...the face in the previous post was suppose to be

Dan,
The several techniques offered will work.
some tips : A stub tenon in the bottom of the post sitting in a mortise cut in the pt 2x12 addresses lateral movement of the post bottom.
Strap hold downs with multiple nails are just plain ugly and I am not a fan of several closely spaced nails along the grain in the post. Use a slightly heavier piece of steel expoxied and lagged into the outside face of the foundation, passing by or going thru the narrow face of the pt 2x12 and then lagged into the outside face of the post with a couple of 3/8 lags spaced about 6" inches apart vertically with the lower one at least 3" up from the post bottom.
deralte

Emmett,
Actually, There will be an 8x10 sill sitting on the 2x12 PT. The posts are all stub tenoned into the 8x10 sill. My question was what is the recommended way to fasten the 8x10 sill down to the PT 2x12 that is fastened to the foundation wall. The 8x10 sill will stand on edge giving 10" of sill height. Should I strap the posts to the sill? There's quite a bit of weight to the structure.

dan,
As others pointed out strapping to the 2x12 has risk. Using an "L" bracket screwed to the 2x12 is also suspect unless the horizontal section is also jbolted into the concrete thru the 2x12/
Leads me back to my next previous response, a 3/16 steel strap lagged into the exterior post face and passing thru a slot in the 2x12 then in turn expoxied and lagged into the concrete will give you the greatest hold down. There are epoxy cylinders which are inserted in your drilled holes in the concrete which crush from the lag screw. Net is very very strong connection. Don't let a hurricane turn your castle into matchsticks.
There are other systems more complex in execution but this method is in my view the best compromise for strenght and ease of execution. In some cases the outside face of the post has been routed to the depth and shape of the steel strap so the face of the post is still one plane.
Hope this helps.
deralte

On one frame we did, with a timber sill over a pt sill we had the concrete guy place 1/2" threaded rod into the concrete looped under a piece of rebar and it was tall enough to come up through the timber sill. We located the rods and bored through holes and lowered the sills down over the threaded rod. Attached nuts and washers and then cut off the threaded rod below the top surface of the sill for the decking to cover it.
Worked ok for us.....

Jim Rogers

Yea Jim,
Still a practioner of prior planning, Good system and simple in execution. Strong too.
deralte

Just to throw in something to think about--Referring back to Paul's observation that in stick houses the sill is anchored to the foundation with embedded bolts but the framing above that is only toe nailed to the sill. If one anchors timber sills with cast-in bolts or all-thread, and the rest of the frame is joined to the sill with pegs, is there an advantage to using sill anchors with a gazillion pounds of holding power but having the rest of the frame being anchored with pegs that have only a 1/2 gazillion pounds of holding power? Using the weakest link theory I'm inclined to favor a little more emphasis on holding the posts down with one of the aforementioned techniques. Of course it's all overkill....when the frame is done the weight of the bills will hold it in place.

This post is attached to the box sill with pegs:



But again the box sill is just toe nailed to the mud sill. But with the sips attached the the posts and the box sill the post is being held down again.

The real concern is with up lift if you're in a high wind area. If this is the case then proper post to foundation connections, that Paul has mentioned, should be used.

Jim Rogers

Has anyone seen the latest Fine Homebuilding issue? There is a story about a timberframe and I would be curious as to what everyone thought about the connection between the posts and the sill....

A good carpenter is taught to nail his sheathing to the anchored mudsill, the “box” is toed to the “mud” only to straighten it to the snap line.(Jim, thanks for speaking - not so New English) This is part of the straightening
and squaring process, more than it is a structural connection.

Hundreds, maybe thousands of 8d‘s. in shear.

I’d imagine an informed inspector, is looking for just this.

Redundancy is an important part of stick building,

And should not be overlooked in what we do either,