Post-To-Foundation Questions

[FrankLad]

I'm looking at different ways of building the foundation and anchoring the posts.
(( I'm planning on a 52x40 house...and have switched my mind from using 6x6" posts to 8x8" posts spaced farther apart. ...10 feet high in either case - maybe 12 feet if I use 8x8...... ))

I would like to stay away from using treated lumber for the posts (or any inside wood, for that matter).  I can do this by using some metal anchors (wet-installed) that have 1" or more standoff plates to keep the wood away from the foundation.  However, someone recently informed me that it may be better to have the bottom 3 feet (or however much is required) of the posts sprayed (I assume with some type of chemical sealer/protectant/treatment) and embed the posts directly into the foundation.  I am a little scared of doing it this way due to the long-term effects.

So there are a few options:
    - Metal Anchors
    - Metal Straps
    - Post-in-Concrete

Likely I'll build over crawl-space since I'll need that to run air ducts...and make the plumbing a bit easier.


I would like for you guys to weigh in on this and give me some feedback based on your experience.

Thanks!

[beenthere]

I'm looking at different ways of building the foundation and anchoring the posts............
However, someone recently informed me that it may be better to have the bottom 3 feet (or however much is required) of the posts sprayed (I assume with some type of chemical sealer/protectant/treatment) and embed the posts directly into the foundation. 

I would seriously question the 'informer' who thought embedding wood in concrete would be 'better' than what you had planned. I would come to the conclusion that 'someone' didn't know what he was talking about.  But I don't know everything, so maybe there is a magical spray to seal and protect wood from decay while entombed in concrete.    I wouldn't put any money on it though. 

"It may be better......." from a structural standpoint, as the concrete would add some side bending resistance, or whatever to the rigidity of the structure.  But one loses that feature when the post rots off.   Maybe these posts will be dry (real dry) and be protected from any chance of gaining moisture, so will not rot. Or maybe the posts will be decay-resistant species that also will not rot. Several things to think about and plan for.   I'd go with treated wood in concrete.

[t_andersen]

I'd go for the metal anchors, no gambling that way

[FrankLad]

That's what I thought you guys might say.  So the post-directly-to-concrete is out of the question.  Even if it was sprayed I think it would still bother me.

As far as the post anchors, I was initially looking at the SocketSystems ones, but am holding off on them until I research the company a bit more.

Simpson Strong Tie is obviously reputable - They've been recommended quite a bit.  Here's something specific I'm looking at now:
http://www.strongtie.com/products/connectors/ab-aba-abe-abu.html

Have any of you installed these before?

[beenthere]

.....  Even if it was sprayed I think it would still bother me.
....

If there is such a 'spray' that would protect wood from rotting, it would be a gazillion dollar breakthrough in the world of 'wood' that someone would hear about.  If there is, I'd sure like to hear about it.   

[Jim_Rogers]

I have posted lots of info and pictures about posts to foundation on this site.
Use the search function above or search yourself and see the stuff here.
DO NOT EMBED WOOD IN CONCRETE..........
Wood will wick water out of concrete and rot, any wood.
We always put a waterproofing membrane (ice and water shield, tar paper, asphalt shingle, something) between the post bottom and the concrete.
Read, read, read.
Lots of info out there, that is correct.......

[Paschale]

So Jim...what if someone went ahead and already did what you mentioned shouldn't be done.   :  I had an emergency fix that needed to take place last fall--the middle support post of my garage was rotting, and I feared that the whole thing would come down.  I jacked up the two garage doors, cut the post, rented a concrete saw and dug out the old and rotten cement.  I called my uncle who's built a lot of houses, and asked what he suggested.  He mentioned that a lot of pole barn builders just go ahead and submerge the pressure treated wood right in the concrete.  Not having much time to make a decision, I went ahead with his suggestion.  Now I'm worried about it--maybe nothing can be done at this point, and I should just not worry about it for the next five to ten years or so.  I guess I don't think about how porous concrete is, and that of course moisture would wick into wood nearby.  Maybe putting a concrete sealer on the surfaces near the posts would hope eliminate some of the seepage of water into the concrete, though I don't know anything about that sort of thing...which is why I ask a lot of questions on here!  I need some learnin'   :P

[mark davidson]

I don't think it's a big deal to bury one post. especially if it's a rot resistant species or has been treated with those terrible poisons(rot resistant wood is a better deal, in my mind). If the posts rots later, throw a sono tube under it and you're away to the races.

burying all you posts is a different matter, as jim points out and not a good idea for timberframing but ok for pole buildings(we have a 50 year old pole building on our farm in which the post bottoms have resisted being buried in manure year after year and those posts still stop a tractor).

As far as concrete connectors go another option is timberlinx:
http://www.timberlinx.com/
these folks make high quality metal connectors for most timber configurations, including wood to concrete

[Furby]

Paschale, part of the deal here is that there are different grades of treated lumber.
Most PT wood is for above grade applications with no earth contact.
If you used a PT 4x4, chances are it is for above grade. A lot but not all PT 6x6 are treated for ground contact.
People go out buy a bunch of PT 4x4s and put up a fence, only to have it blow over in a handful of years when rot sets in. Those 4x4s were for above grade most times.

Either case, what's done is done. You should get some use out of it and like Mark said, it can be fixed at a later date if needed.

[beenthere]

Paschale
You can be the 'test' site, and keep us "posted on the post" over the years.  It may surprise you how long it will last, but on the other hand...........you can then just change it out again when necessary.

Furby knows.....  plus a heart-centered 4x4 is heartwood which doesn't treat anyway.  Only the sapwood takes treatment, so its just the natural resistance that protects the heartwood anyway.

[Jim_Rogers]

Paschale,
I wouldn't worry about it now. If you keep this embedded post as dry as possible by having the siding cover it should be ok.
You'd probably do more damage to your structure trying to change things.
Let it go, but over the years keep an eye on it.
Jim Rogers