Go Back   DIY Chatroom Home Improvement Forum > DIY Repair > General DIY Discussions

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 02-14-2009, 07:42 PM   #1
Newbie
 
Join Date: Feb 2009
Posts: 4
Rewards Points: 0
Share |
Default

supporting a floor joist


Any suggestions on the best way to support a sagging floor joist? It's under house with about about a two foot clearance from ground to joist.

havens is offline   Reply With Quote
Old 02-14-2009, 08:25 PM   #2
Master General ReEngineer
 
Bondo's Avatar
 
Join Date: Dec 2007
Location: Chaumont River, Ny.
Posts: 3,683
Rewards Points: 0
Default

supporting a floor joist


Ayuh,...

How about a stack of Blocking, 2', 1/2" tall,..??

Bondo is offline   Reply With Quote
Old 02-14-2009, 08:56 PM   #3
Member
 
cocobolo's Avatar
 
Join Date: Dec 2008
Location: Gulf Islands, B.C., Canada
Posts: 6,631
Rewards Points: 2
Default

supporting a floor joist


Havens, is it just one joist that is sagging? Or is your whole floor sagging?
In the crawl space (I'm assuming here, yes I know...) is there anything other than dirt beneath your floor framing? Can you get a picture? What size is the joist(s)? Any holes in the joist in question? New? Old?
cocobolo is offline   Reply With Quote
Old 02-14-2009, 09:34 PM   #4
Newbie
 
Join Date: Feb 2009
Posts: 4
Rewards Points: 0
Default

supporting a floor joist


House is about ten years old. Only one joist is sagging. Is a 2x8 , no holes. Sand under house.
havens is offline   Reply With Quote
Old 02-14-2009, 10:43 PM   #5
Member
 
cocobolo's Avatar
 
Join Date: Dec 2008
Location: Gulf Islands, B.C., Canada
Posts: 6,631
Rewards Points: 2
Default

supporting a floor joist


OK, shouldn't be a problem. You might try getting a concrete paver, or perhaps 2, set them on the sand, one atop the other, and pound them into the sand with a rubber mallet. This will give you a reasonably solid footing.
Using whatever means at your disposal, a hydraulic jack for example, lift the joist until it meets with your satisfaction. Measure between the joist and the concrete paver(s), and cut yourself one 2 x 4, or 2 x 6, whatever you have at hand, 1/4" longer than the space. Then cut yourself two more 2 x 4's or 6's, whichever you have, but make them 7" longer than the first 2x.
Raise the joist up the extra 1/4" and put the first 2x in place vertically. Let the jack down.
Before you take the next step, take a good critical look to see if you are satisfied.
If all is OK, then nail on the other two 2x's, one on each side of the first 2x.
You have just constructed a post which will not move out of place and which will give you full support. Use lots of nails.
Good luck.
cocobolo is offline   Reply With Quote
Old 02-15-2009, 02:02 PM   #6
Member
 
Join Date: Apr 2008
Posts: 294
Rewards Points: 0
Default

supporting a floor joist


Just a thought if it's just one joist.

It would help if you could determine why it's sagging? Was it bowed when it was installed? Heavy weight setting directly over it that caused it to bow, like a wall? What is the spacing between joists? Etc.

If it looks structurally intact then I'd just try jacking it up slowly, careful to brace it as you go, and then sister another 2X8 alongside it with lag screws. Remove jacks and bracing.

Again, it would be worth while spending some time to understand why it ended up that way before you do anything. If you have concerns that go beyond what you've posted it might be wise to get a Pro to offer their opinion.

Just my 2
__________________
Shamus
Shamus is offline   Reply With Quote
Old 02-15-2009, 02:24 PM   #7
Newbie
 
Join Date: Feb 2009
Posts: 4
Rewards Points: 0
Default

supporting a floor joist


Thanks for the information. I don't think this joist ever had any support under it and that's why it sagged over the years. Thanks again.
havens is offline   Reply With Quote
Old 02-15-2009, 03:25 PM   #8
Member
 
cocobolo's Avatar
 
Join Date: Dec 2008
Location: Gulf Islands, B.C., Canada
Posts: 6,631
Rewards Points: 2
Default

supporting a floor joist


Is this a joist or a beam?
cocobolo is offline   Reply With Quote
Old 02-15-2009, 03:43 PM   #9
Newbie
 
Join Date: Feb 2009
Posts: 4
Rewards Points: 0
Default

supporting a floor joist


It's a joist.
havens is offline   Reply With Quote
Old 02-15-2009, 05:14 PM   #10
Member
 
cocobolo's Avatar
 
Join Date: Dec 2008
Location: Gulf Islands, B.C., Canada
Posts: 6,631
Rewards Points: 2
Default

supporting a floor joist


It seems odd that just one joist would sag, and not the adjoining ones. This must mean that you have a dip in the floor just in that very limited area. It is always possible that the joist was accidentally installed crown down.
Is there any blocking between the joists across the floor? If not, this is a problem which you can quickly address.
cocobolo is offline   Reply With Quote
Old 02-15-2009, 09:11 PM   #11
Household Handyman
 
Join Date: Feb 2009
Location: Albany, Ga.
Posts: 2,270
Rewards Points: 0
Default

supporting a floor joist


I've done many of these in my home repair business and the #1 question is still--why is it sagging. This question has to be solved. IF you can easily gain access to under the house/flooring go under there and just lie there looking at how everything is constructed, imagine what is actually on top of the sagging joist and solve the sag problem first. Do you have a digital camera? I always take pictures when I go under a house to investigate anything. Showing the homeowner the pictures on my laptop is a real seller. Take pictures, you can study these after you come out. cocobola's solution is the closest to the method I recommend. I use two 16" square pavers from a local Lowe's or HD store set on top of each other and leveled. I prefer to use pressure treated 4 x 4's cut 1/4" longer than my gap with the joist leveled out, jack the joist up and put the brace in place. I've never believed a properly placed brace will move but I use 12" pieces of PT 2x4's nailed to the joist, butted up to the brace to hold it in place. How far is the span of the joist, could it just be that it is a bit too far and is over stressed? A sister joist is not a bad idea with the bracing also. Thanks, David
Thurman is offline   Reply With Quote
Old 02-15-2009, 10:22 PM   #12
Member
 
cocobolo's Avatar
 
Join Date: Dec 2008
Location: Gulf Islands, B.C., Canada
Posts: 6,631
Rewards Points: 2
Default

supporting a floor joist


Thurman: Certainly no problem dealing with a P.T. 4x4. It would still be good to find out if there is any cross bracing or blocking between the joists. If there was, just one joist should not have sagged.
And you are right about finding the problem.
It may be something as simple as one or two large knots on the same side of the joist causing it to buckle.
So we still need to know the span. And it wouldn't hurt to find out what sort of weight is on top either.
cocobolo is offline   Reply With Quote
Old 02-16-2009, 09:22 AM   #13
Member
 
Join Date: Jun 2008
Posts: 842
Rewards Points: 0
Default

supporting a floor joist


This remedy discussed here would be called random support and trigger a BIG question mark on an appraisal or home inspector report. I would lean towards sistering a new joist to one or BOTH sides,,especially IF this is sagging due to a heavy wall built (above it)so only this joist is supporting it!!
4just1don is offline   Reply With Quote
Old 02-16-2009, 02:26 PM   #14
Member
 
cocobolo's Avatar
 
Join Date: Dec 2008
Location: Gulf Islands, B.C., Canada
Posts: 6,631
Rewards Points: 2
Default

supporting a floor joist


If there is a heavy wall above it, then the floor should have been built to accommodate it. Let's find out what is there first.
Your point about a future house inspection is well taken, but better be fixed than not.
Perhaps a full supporting beam from one end to the other will be in order if that is the case.
When we know what it looks like, I am certain there will be more than one suitable option to fix it.

cocobolo is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Bracing for supporting walls Bradley P Building & Construction 8 01-22-2008 07:44 AM
supporting in the basement bcoots76 Building & Construction 8 12-20-2007 05:37 PM
Supporting girder with wall Geber Carpentry 3 01-29-2007 09:53 AM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.