DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (
-   Carpentry (
-   -   Beam Replacement? (

Steve Dailey 05-16-2008 12:59 PM

Beam Replacement?
While doing some work in my crawlspace, I noticed a problem with the main support beam. My home is a ranch, about 80 X 50. In the foundation there is a beam pocket where this beam rests. Under the wood beam it looks like there are two pieces of wood that this beam rests upon. The problem is one of these two pieces of wood ( approx. 1 1/2" high ) has completely rotted away and has collapsed under the weight of the house upon this beam. I want to replace these 2 pieces. I have about 12 bottle jacks so I can try to jack the beam up about 1/4 " at a time.
The problem is, when I try to jack the house up all I am doing is smashing the wood beam in. I am using a piece of 1/4" steel between the beam and the jack, but the beam is still being smashed. I guess I will have to replace the whole beam. How can I support the house while I replace this beam. There are about 5 - 4 X 4 posts that this beam is sitting on to the center of the house. These posts are also smashing in the beam from 1 1/4" to 1/2' all the way down the line. Can anyone out there give me any suggestions of what to do? Steve

buletbob 05-16-2008 06:39 PM

I have done many of them in my day. First what is the height of the crawl? is there a cement slab on the floor? and do you have a poured concrete foundation or is it block. What I'm trying to arrive at is how did this accrue. termites. dry rot. or black mold. please get back to me. BOB.

Steve Dailey 05-18-2008 08:56 AM

Beam Replacement
Bullet Bob,
The height of the crawl is approx. 42" high. It has a poured foundation wall and a gravel base. About every 8 Ft. there is a 4 X 4 post that the beam sits on and in turn this posts sits on an 18" X 18 " concrete pad that sits in the gravel. I have assembled 5 towers out of 4 X 4 's and set them on a 12 X 12 piece of 5/4" plywood. These towers are just about the height I need to place my 12 ton bottle jacks directly under the beam. Of course when I try to raise the beam the steel plate only embeds itself in the wood. My brother says that I need to put down some moisture barrier on top of the gravel after this project is complete so this won't happen again.
I can't figure out what I need to do to replace this beam! Any help will be appreciated.
Thank you, Steve

buletbob 05-18-2008 08:51 PM

Steve what is the size of the existing girder. if you had a cement crawl space it would of been a lot easier for a DIY'ER, now that you say you have gravel it would be a lot harder.
doe's the entire girder have to be replaced. or just part. and what length. is there a bearing wall above? get back to me with this info. and if you still want to go ahead with this project I'll Walk you threw it step by step.
what you are referring to towers, we call them cribs here on the Island.
get back to me BOB

Steve Dailey 05-19-2008 09:51 AM

The "girder" is made up 2-10 X 2's. Each one is about 10 feet long.
They are staggered at the point where they sit on top of the 4 X 4 posts. I think really only the first 5 feet nearest the beam pocket needs to be replaced. This is a brick, ranch home, built in 1972. This girder runs directly down the center of my house. The wall directly above this is in my hallway and above that wall is another girder that supports the joists above my ceiling. Also, once I am able to jack my floor up to replace a section of this beam, what type of material do I put under the beam to replace the rotten 2X's that were used in the beam pocket? I don't think any of the materials that we have been talking about were made with "treated" lumber.
Thank you, Steve

buletbob 05-19-2008 08:46 PM

Steve! Is what your saying is the girder only has to be replaced from the first and second post. correct ?. then this will be easy. it was my understanding that the interior beam had to be replaced.
Get your self 4 6x6's about 8ft long. build your cribs on either side of the girder in question stay off the wall about 16" and set the other crib in line with the first post and the next crib about 16" from the inside of the 2nd post.
measure the height of the jacks you are going to use on each crib and add 5-1/2" to the total. now minus 1-1/2" . this is going to be the height of your cribs. at the top of each crib put another 4x4 under the bottom center of the jack install your plywood.
set you jacks on the first and last cribs and install your 6x6's on top. the center cribs are going to have the 6x6's overhang each other , side by side .you will have to make the center cribs 3-1/2" lower because you going to install a 4x4x16" under the two 6x6's and on top of the jacks.
when doing this make sure everything is as close to center as possible. you don't want to have the cribs lean out.
Now start jacking the 6x6's up until they snug up to the bottom of the floor joists. go up about 1/2" on each jack and then another 1/2" until all the floor joist are up and the top of the girder is about 1/4" higher then the sill plate.
start cutting out the damaged girder. cut all nails hanging down from the floor joists.
pick up some doug fir #2 or btr. and make up the new girder. you stated there was two, normally there should of been a triple. if so make it up accordingly. when you install the girder in the beam pocket bend some alum trim stock to cover the wood that makes contact with the foundation.
measure the height of the girder 9-1/2" ?. and then measure down from the sill plate next to the pocket and put a mark on the foundation wall. mix up some fast drying high strength concrete and pack it in the bottom of the beam pocket to the mark you just made. when that drys lower the floor down on to the posts, string a line along the bottom of the girder cut new post as needed. don't forget to nail the floor joist back into the girder. let me know how you made out. good luck BOB.

All times are GMT -5. The time now is 04:18 PM.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

Search Engine Friendly URLs by vBSEO 3.6.1