Hello everyone,
I’m new to this, but I here I go….In designing an addition with a crawl space foundation the best way I have come up with to tackle some issues I’ve identified is to have beam pockets created when the new concrete foundation is poured. I will have 2 x12 ‘s resting in the beam pockets, the pockets will be 4″ wide for air movement around the joists and will be 3″ deep.
My question is – for the depth of beam pocket, should I design in an additional 2″ in depth to rest the joist on a scrap of pressure treated wood. Or should I just wrap the end of joist (or bottom half) that touches the concrete in WR Grace “Ice & Water Shield”? Any other ideas are welcome too! Thanks.
Replies
Rest the beams on galvanized steel, something in the 16 ga. range, not duct metal, and level them with oak shims. Shims above the sheet metal, obviously. IMHO.
I would create the pockets with an extra 1-1/2" for using PT as a bed.
I would recommend that you ask your local building inspector what his interpretation of the code is for your locale. In some places the bituthene wrp would suffice.
You will want to use shims to stabilize the beam and keep it from rolling in the oversized pocket.
Excellence is its own reward!
If you weren't already planning on it, I'd recommend that you allow a little extra behind (at the ends of) the beamage for air circulation as well as at the sides.
Average Joe says:
I'll wait here while YOU go wrestle the wild alligator.
I'm a little curious about the use of 2 X 12's as "beams"...if you're installing girders or beams to support floor joists they are normally (in my experience anyway) 4 X's or larger. In any case, I usually do as Piffen suggests; rest them on a piece of PT. I usually use 3/4" PT plywood because it shrinks very little. Leave a little room all the way around so the wood beam is not in direct contact with the concrete.
Notchman had the right idea and Simpson has just the ticket for you. Use a Girder Hanger, they are available for 4x6 and 4x8 and for foundation walls 6" wide and 8" wide. I just used them on a raised floor foundation. With a 2x6 mud sill the 4x6 girder top is at the same level as the mud sill. Then just lay out your 2x6 floor joists and rim joists and you're done. Best of all no pockets to form in the concrete.
Bing
Designbing has the right shot on this. Use the Simpson brackets, they set right into the wet concrete in the sill plate. They are made for whatever size post or beam you have Get a catalog. Good solid contact. Consider timberstrand as well. Better than lumber cheaper than LVL but not as strong. Whatever you choose you can make the beam top flush with the floor and use Simpson hangers for mounting the ends of the joists to the side of this beam. This way the height you used by laying the joists on top of the beam can be saved in the crawlspace.Jack of all trades and master of none - you got a problem with that?
Is this the type of hanger you're talking about ?
http://www.strongtie.com/products/connectors_list/GH.html
I'm generall not in favor of hanging joists on the face of beams - Makes it hard to run mechanicals. And it invites plumbers/electricians to drill holes through the beams to run their stuff in.Yesterday I went fishing with dotted line. I caught every other fish.
the PB is what I was thinking. Then LUS or HUS to hang joists to the face of the horizintal beam mounted in the PB.
Frankly the thought on the beam sitting on a plate of PT wood seems reasonable as the rest of the structure sits on the same plate. But then you are closer to this. What do you think?
As for the face hanging, As long as the electrical goes thru the center of the beam all is good. If you do it yourself you have control. I do see your point.
Jack of all trades and master of none - you got a problem with that?
Edited 3/5/2003 9:46:41 AM ET by Booch
"the PB is what I was thinking."
The only "PB" I could find was a Post Base.
"..the thought on the beam sitting on a plate of PT wood seems reasonable as the rest of the structure sits on the same plate. But then you are closer to this. What do you think?"
I don't have a problem with that. But you're assuming that the beam is the same depth as the floor system. That's only true about half the time around here.
"As long as the electrical goes thru the center of the beam all is good."
Not necessarilly. Depends on the beam material, manufacturer's recommendations, local codes, and how stressed the beam is. Sometimes it's fine, other times it isn't. We in the industry know that behind every successful screenwriter stands a woman. And behind her stands his wife.
I guess I don't see much difference between the use of the post base to pacify the placement of a beam or a column. Is there a problem?
As for the depth differences. I have a 5.5" x 12" timberstrand that holds 11 7/8 I joists.
The size of the beam makes a big difference as does the location of the holes from the ends. Timberstrand literature covers that pretty well.
Good points.Jack of all trades and master of none - you got a problem with that?
The type of hardware I was asking about was when DESIGNBING was talking about hanging the beam off the foundation in message 28180.6.
I thought you were saying that you were using a type of hanger that started with "PB". But I gather you're talking about sticking a post base inside the notch in the foundation?Those are my principles. If you don't like them, I have others.
My thought was captivating the beam by setting it on the top of the foundation inside of the PB. Then the I joists hang off the side of the beam with the beam hangers and the other end lands on the foundatain as well. everything is in the same plane. Wrap a rim joist around the exterior and all is good. I'm avoiding the pocket.Jack of all trades and master of none - you got a problem with that?
I think I firured it out! cpc is going to pocket every joist? is that correct? on both ends?hope he has a good concrete man so all those pockets line up.seems like i remember something about fire codes and beam pockets and floors and ceilings collasping easily when constructed in that manner when theres a fire.probably wont have any fire fighters in the crawl space though. sure would like to see a drawing of what cpc is trying to do sounds like a lot of extra work.but maybe iam not clear yet..
The caution about asking local inspection is good as here no wood shims are allowed. Here shim stock must be steel or the composite type used for steel beams.
__________________________________________
Remodeling Contractor just outside the Glass City.
http://www.quittintime.com/
Why use 2x12's and fight the crowns and shrinking? LVL or steel I-beams are easier and more stable. you can often get used I- beams from a steel scrap yard and they use up less depth in basements and even crawls where you might be running mechanicals.
Some areas won't allow any wood shims under the beam. (I do see it uses frequently, and the only time it's been a real problem is where there is a significant moisture problem in the crawl, as well.
If you use stell, be sure to have the top of the stell level with the top of the foundation and run a "sill" plate on top of it so the floor doesn't hump.
_______________________
"I may have said the same thing before... But my explanation, I am sure, will always be different." Oscar Wilde
Thanks for all your suggestions! I appreciate the variety of thoughts and quick responses.
Chris
I don't understand why your pocket is only 3'' deep.Maybe I mis-read your post, or I'am not clear on what your trying to do but typically the beam is level with the top of the foundation sill plate. Use a steel w beam there easy to shim,and wont roll around either, negating the use of blocks on the side of the beam pocket to keep it from rolling around. Steel is cheap and the steel supplier will set the beam too.
"Steel is cheap and the steel supplier will set the beam too."
May YOUR steel supplier does. But not all do.A man's only as old as the woman he feels.
True some do and some dont set the beam, why dont you find one who does?Steel Beam Service Grain Valley MO(just kidding around with you) but at any rate steel is a better choice than a built up beam and even if they dont set it you could wrestle it in there with four or five guys.i dont what the length of ''cpc's'' beam is but the last W beam i set was a 10 x 26 48 foot continous so it weighed 1248 pounds and iam guessing cpc's addition is not 48 feet in length which would allow a couple of people to set the beam in the pockets if beam depth is a concern then again steel would have a shallower chord depth.perhaps a W 8x15 16' long=264 lbs is easily set by 2 people. Maybe Iam not seeing the picture clearly or being thick headed but would you or anyone else tell me why cpc's beam pockets are so shallow??? never seen a center beam sticking up above the foundation walls.One more thing whats the dimensions of the addition? is a beam even needed? the other thing that confused me is in the second paragraph the terms "beam" and "joist" seem to be used as if there the same thing. thanks for any clarification.
Wasn't trying to pick an arguement - Just make the point that services vary a lot from state to state, and even from town to town. So don't assume that what happens locally for you will work everywhere.
BTW - Use a few paragraph breaks, and it will make your post easier to read.Solomon made a book of proverbs. But a book of proverbs never made a Solomon.
i knew you were not trying to argue no prob. i was just kidding around. my poor attempt at humor. the company i use is almost, at the very least 60 miles one way from my site.
There were 2 beams the cost was more than $300.00 but less than 1000.00 and they set it too. it was 18months ago or better so i dont really recall the exact amount.
But i dont think Ive got my head around what cpc's post is saying ..help me out?Forgive me if iam being stupid and not understanding the original post.
I'm not sure I understood the original post either. All the messages to him are marked as read, so he saw them. But he never came back and explained himself more. Maybe he will yet.On the first day of school, the kindergarten teacher said, "If anyone has to go to the bathroom, hold up two fingers." A little voice from the back of the room said:"How the hell will that help?"
Xray
Boss doesn't even know where Grain Valley is<G>.
I checked your profile and see that you are in Larry KS and wonder how you know where GV is?
I am at Lake Tapawing, on the western edge of Blue Springs.
"Boss doesn't even know where Grain Valley is"
How do you know ???
Definitely never heard of Lake Tapawing or Blue Springs though.What kind of redneck town are those?...............(-:Q: How do you stop a lawyer from drowning?A: Shoot him before he hits the water.
I figured with all the corn fields in IL that you could not see that far.
BS and GV where little country towns that are now part of the Kansas City suburbs.
Lake Tapawingo is 100 A lake and homesites that was started in the 20's with summer cabins way out in the woods. Rummors had it that during prohibition that sea planes brought in liquor and there where some remains of stills in one of the houses.
LT, BS, and GV are all right off I-70 just east of Kansas City.
BTW, I am from Louisville so I take 1-70 to St Louis and then I-64 when I go back home.
Anyway, one year because of construction I took a different path around St Louis and then made the wrong exit and ended up on I-70 in IL. Got about 1/3 of the way across the state before I realized the mistake. All of the corn fields and small towns 2 miles off the interstate all look the same.
I grew up in kansas city