Replacing Sagging Main Beam


  #1  
Old 02-07-10, 02:40 PM
B
Member
Thread Starter
Join Date: Feb 2010
Posts: 2
Upvotes: 0
Received 0 Upvotes on 0 Posts
Replacing Sagging Main Beam

I have a main support beam in my basement that is sagging enough in the middle that doors on the first floor are sticking in their frames.

The house is 20 years old and the existing beam is 3-2x12s (side by side) with a span of 12'8". One end of the beam rests on top of a concrete foundation wall and the other end is on top of a steel column.

Would replacing it with an engineered wood beam provide greater resistance to future sagging?
 
  #2  
Old 02-07-10, 03:41 PM
B
Member
Join Date: Oct 2008
Location: New England
Posts: 9,460
Received 47 Upvotes on 43 Posts
Yes, but correcting 20 years of gradual sagging and wood shrinkage isn't going to be easy on the rest of the house.

My recommendation would be some intermediate supports on a proper base to stop the sagging, remove a bit of it, and begin the process of going the other direction. If you are doing a major renovation, then jack her up and slide in a new beam. But along with that you may have to repair some walls and doors.

Part of the problem is not just the sagging. Example: My triple 2x12 measured 11 1/2" when installed. It now measures 11 1/8". The outside walls are held in place by the sheathing, but interior walls all rest on that beam. Add in the sag and I'm down almost an inch in some places. I placed 6 supports in the low spots and brought up the pressure until I started lifting the beam off of the old posts. 6 months later I was able to give each another push and again lift the beam off the old posts. Each time I return, the beam has settled back onto the old post, so I'm slowly making progress. But I will stop at some point short of a perfect level, as what I'm looking for is closing some cracks and proper working doors. Sound familiar.

Good luck,
Bud
 
  #3  
Old 02-09-10, 07:38 AM
B
Member
Thread Starter
Join Date: Feb 2010
Posts: 2
Upvotes: 0
Received 0 Upvotes on 0 Posts
Thanks for your thoughts. I had assumed that all of my settling was due to sag in the support beam, but will check to see if the column supporting one end has settled (likely), then proceed slowly with getting things back to level.

Bill
 
  #4  
Old 02-09-10, 08:22 AM
B
Member
Join Date: Oct 2008
Location: New England
Posts: 9,460
Received 47 Upvotes on 43 Posts
When you see some of the older homes that look like an old swayback horse, high on the gable ends and saddly low in the middle, consider the shrinkage of all of the wood. On the ends, the sheathing maintains the true length more so than in the middle, where the accumulation can equal an inch or more. If you were to jack up the first floor until the roof line was level, the floor would be bowed up, walls cracked and doors in trouble. To get each floor/ceiling back to level, would be a difficult task. That is why I like the go slow approach, as you can see the progress and stop where needed.

Bud
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: