Missing support walls

Reply

  #1  
Old 10-14-12, 07:29 AM
Member
Thread Starter
Join Date: Oct 2012
Location: usa
Posts: 3
Missing support walls

Hello people, new to the forum ..... will explore the threads as time goes on but I do have a situation for you to comment on with your experience.

I have an old house appx 100 of which I am in the process of remodeling. First off the foundation is a perimeter beam and highly doubt it has piles or rebar. The floors are not straight in half the house because of this as a few sections of the perimeter beam have cracked and deviated from the rest of the perimeter. Plan is to lift and pour a full basement next year. Here is my situation. it looks like two load bearing walls were removed prior to my reno to make living spaces bigger. The sag of the ceilings is about 1 inch in the middle at the top plate. One wall does have one of the foundations perimeter beams supporting from underneath the other does not. I would like to put beams in place before the house is raised and dropped on the new foundation. Since the original wall is gone I obviously can't build temps and put a beam in like it should have been done in the first place!! 1) Easy one first (foundation supported wall) Thinking I can get a suitable I-beam put it in place against the ceiling and through the use of a hydraulic jack and suitable column, jack up the middle of the beam (thinking to use an I beam as well on the floor to spread the load as I jack it up) until the sag in the ceiling is gone then build in my supports against the wall, remove jack. 2) (unsupported wall) same process as above but in this case build a supporting wall under the floor in the basement to provide the support required to jack that ceiling. I would like to have these beams in place before I lift the house OR will the beams be out of place once I do raise and level the house again? Can I leave some space at the ends of the beam as to not induce interference on the adjacent walls once the lifting of the house takes place? The length of beam required is 9' and 10.5' in each case, so its not a huge distance. If your curious why I want to use an I beam its to get the smallest cross section possible and beam support to avoid a huge box in later if I used 2x12's of wood instead.

thanks ahead of time for the input.
 
Sponsored Links
  #2  
Old 10-15-12, 03:43 PM
Temporarily Suspended
Join Date: Jul 2008
Location: NY
Posts: 10,986
Why did you say "new foundation"? It's not a new foundation, it will be a rebuilt foundation. Anyway, the house has to be raised before new supports, columns or walls are installed.
 
  #3  
Old 10-15-12, 07:11 PM
Nashkat1's Avatar
Member
Join Date: Mar 2012
Location: USA
Posts: 8,470
Support starts from the ground. Consult with your house moving contractor to design the best plan.

BTW, lifting a wall is not done with beams placed in line with it. It is done with beams placed across it, to allow space for the permanent support to be built.
 
  #4  
Old 10-15-12, 08:58 PM
Member
Thread Starter
Join Date: Oct 2012
Location: usa
Posts: 3
@pulpo .... new foundation meaning "raise the house, completely remove the existing foundation and have a new foundation formed and poured to current code, house dropped back down thus giving me a NEW foundation/basement" i'm not repairing the existing.

@nash ..... yes bearing walls are perpendicular to the joists .... as I said the walls that were removed were bearing walls and i want to put a beam in place like it should have had in the first place once those walls were removed. im not lifting a wall ......

the beams im talking about adding are the ones in lieu of the missing bearing walls that are supporting the second floor (upstairs), gut tells me i need those bearing beams in place before i lift the house to pour a new foundation....
 
  #5  
Old 10-16-12, 01:57 PM
BridgeMan45's Avatar
Member
Join Date: Oct 2011
Location: USA
Posts: 3,196
I think you're on the right track. Wedge the 2 steel support beams up tightly against the ceiling, taking the sag out of it before proceeding with the house lift. And make sure the end support columns holding the steel beams are resting on something solid in the basement (bearing wall or columns) before doing so. Trying to raise the house with no ceiling support where the bearing walls were removed is asking for problems; your house mover/lifter will tell you that as well.

For a 10' span, you'll want to use a beam having a section modulus of at least 5.0 C. I. That's based on having to support a total uniform load of 50 PSF, over a guesstimated 16' span above, using steel with an allowable bending stress of 24 KSI. Something as shallow as an M 4 x 13 would work (miscellaneous or junior beam, 4" deep with 4" x 3/8" flanges, section modulus of 5.24 C.I.). If the anticipated loads are heavier, a larger section modulus/beam will be required.
 
  #6  
Old 10-16-12, 11:08 PM
Nashkat1's Avatar
Member
Join Date: Mar 2012
Location: USA
Posts: 8,470
@nash ..... yes bearing walls are perpendicular to the joists .... as I said the walls that were removed were bearing walls and i want to put a beam in place like it should have had in the first place once those walls were removed. im not lifting a wall ......
I don't think you heard me. I regret that I wasn't as clear as I would like to have been.

You said
1) Easy one first (foundation supported wall) Thinking I can get a suitable I-beam put it in place against the ceiling and through the use of a hydraulic jack and suitable column, jack up the middle of the beam (thinking to use an I beam as well on the floor to spread the load as I jack it up) until the sag in the ceiling is gone then build in my supports against the wall, remove jack.
I said
Originally Posted by Nashkat1
Support starts from the ground.
To expand on that, you cannot lift the sagged exterior wall, or any wall, without lifting below it. Building a lifting rig next to the sagging wall, supported by a beam laid on the floor joists and "lifting" on a beam spanning across the ceiling joists, is a good way to increase the distance between the floor joists and the ceiling joists. It depends on which attachment is weaker whether the ceiling will move up or the floor will move down. Probably some of each. The wall that sagged won't move at all.

Just out of curiosity, how does this work:
it looks like two load bearing walls were removed prior to my reno to make living spaces bigger... One wall does have one of the foundations perimeter beams supporting from underneath...
How can there have been a load bearing wall that supported an exterior wall?

2) (unsupported wall) same process as above but in this case build a supporting wall under the floor in the basement to provide the support required to jack that ceiling. I would like to have these beams in place before I lift the house OR will the beams be out of place once I do raise and level the house again? Can I leave some space at the ends of the beam as to not induce interference on the adjacent walls once the lifting of the house takes place?
It sounds like you're planning to support the framing in this instance from below. build some sort of temporary bracing where a wall may have been removed, and then lift the house, and that wall or bracing, off the support you built below it. How's that going to work?

As I said earlier, I would
Originally Posted by Nashkat1
Consult with your house moving contractor to design the best plan.
Before doing any work on this.
 
  #7  
Old 10-18-12, 04:01 PM
Member
Thread Starter
Join Date: Oct 2012
Location: usa
Posts: 3
Thanks Bridge .....

@nash,both walls are interior walls not exterior walls. the house juts out from the front to make another room, basically the perimeter beam is two squares next to each other of different size thats probably where the confusion is. the concreate beam between the two half is where one bearing wall was (easy one) the other bearing wall had just the floor joists as support, no beam under it. so i planned on supporting the floor underneath temporarily just to jack up the beam to level the second floor above, (didnt want to deflect the floor below) add the cripples, then add additional framing in the floor joists to support the cripple columns then remove the temp support. that wall is perpendicular to the main house beam. one end is right next to that beam so i should be able to support that end nicely, the other end is the concrete beam foundation.
 
Reply

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


Thread Tools
Search this Thread
Display Modes