leaning one room addition
#1
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leaning one room addition
A one room addition with interior floor area of 10 Ft. by 14 Ft. is attached on one longer side of the room to a trailer (mobile home). Down the middle of the addition and along the exterior wall are three 4X4 posts each ( a total of six posts) supporting the room extending out from the trailer. These posts are attached to the floor joists and rest on a concrete pad. There is about a two foot distance from the concrete pad to the bottom of the floor joists.
The one room addition is leaning to one side. One post that I checked with a level was tilting at about a 5 degree angle relative to being perpendicular to the floor joist.
The concrete pad underneath the posts appears to be in good condition without any cracks and according to the level horizontal.
My question is what to do to prevent additional leaning of the room to one side. It does appear that it is the supporting posts that are leaning.
The options that occur to me are (1) install more posts, (2) Use lag bolts to more securely attach the posts to the joists, and/ or (3) install cross bracing.
This is to a large degree unknown territory for me. Thanks if anyone can let me know what to do with this problem.
-Pete
The one room addition is leaning to one side. One post that I checked with a level was tilting at about a 5 degree angle relative to being perpendicular to the floor joist.
The concrete pad underneath the posts appears to be in good condition without any cracks and according to the level horizontal.
My question is what to do to prevent additional leaning of the room to one side. It does appear that it is the supporting posts that are leaning.
The options that occur to me are (1) install more posts, (2) Use lag bolts to more securely attach the posts to the joists, and/ or (3) install cross bracing.
This is to a large degree unknown territory for me. Thanks if anyone can let me know what to do with this problem.
-Pete
#2
What you need to determine is if the post is just leaning or sinking.
How is the addition attached to the mobile home ?
There isn't much to fasten to and your ledger may be disconnecting from the trailer.
How is the addition attached to the mobile home ?
There isn't much to fasten to and your ledger may be disconnecting from the trailer.
#4
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Never ever should have been built like that.
Guessing there was no permits or inspections.
No way would they have allowed 4 X 4's.
Just sitting on a slab is a huge no no.
Should have been sitting on footings below the frost line and a real foundation.
That way the addition would have been more stable then the mobile home.
Guessing there was no permits or inspections.
No way would they have allowed 4 X 4's.
Just sitting on a slab is a huge no no.
Should have been sitting on footings below the frost line and a real foundation.
That way the addition would have been more stable then the mobile home.
#5
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What the local permit office allows isn't the same in all locales. While I don't care for that type of construction, I know of several permitted additions to mobile homes that are built on 4x4 posts 
How are the posts attached to the slab? hopefully not just sitting on them
look forward to seeing the pics

How are the posts attached to the slab? hopefully not just sitting on them

look forward to seeing the pics
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rain today, so limited responses
PJMAX, unless the entire concrete pad is sinking, no, the posts aren't sinking. There is no damage to the concrete underneath each of the posts. Thanks for thinking about the connection of the addition to the mobile home. Hopefully tomorrow it won't be raining and I can try to look to see how they are joined.
marksr the posts are sitting on the concrete pad, not secured to the pad. However this is no better or worse than the trailer.
No photos today as it is raining.
Thanks for the responses,
Pete
marksr the posts are sitting on the concrete pad, not secured to the pad. However this is no better or worse than the trailer.
No photos today as it is raining.
Thanks for the responses,
Pete
#7
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The block piers that hold up the MH are more stable than just a 4x4 post. While the piers can sink or shift they aren't as likely to move as the unsecured 4x4. While not likely [unless there are cracks] the slab could sink some.
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more info
An important thing that I should say is that the leaning is in a direction parallel to the wall of the mobile home that the addition is joined to, not away from it.
Looking underneath at where the add. room is joined to the mobile home, I don't see how the room is attached. It does look secure, though; I don't see any gaps.
It looks like the 4X4 posts were attached to the floor joists by peppering the joints with a nail gun.
In the attached photo, you can see how I attached two lengths of 2X4 to the nearest post to try to reinforce it. Off to the right of the photo you can see some of a 2X4 cross-brace bolted to a floor joist close to the exterior wall of the addition and to a 2X4 attached to two of the 4X4 posts towards the outside of the room.
Any comments?
Pete
Looking underneath at where the add. room is joined to the mobile home, I don't see how the room is attached. It does look secure, though; I don't see any gaps.
It looks like the 4X4 posts were attached to the floor joists by peppering the joints with a nail gun.
In the attached photo, you can see how I attached two lengths of 2X4 to the nearest post to try to reinforce it. Off to the right of the photo you can see some of a 2X4 cross-brace bolted to a floor joist close to the exterior wall of the addition and to a 2X4 attached to two of the 4X4 posts towards the outside of the room.
Any comments?
Pete

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Leaning is not too severe at this point, so given the view of the photo, it isn't going to be apparent in the photo. The 2X4s are not pressure treated; I did not choose pressure treated as underneath the floor of the room is mostly protected from the elements.
Thanks,
Pete
Thanks,
Pete
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Thanks for the guidance about pressure treating.
There are some other signs of the room leaning off to one side, other than tilting of the posts. At the far end of the room in the photo, there are concrete steps for entering the room. The gap originally between the steps and the outside wall of the room is now gone, that is, the wall is butting against the steps. Also at that same end you can see the skirt for the room from bottom to top pointing outwards.
Thanks,
Pete
There are some other signs of the room leaning off to one side, other than tilting of the posts. At the far end of the room in the photo, there are concrete steps for entering the room. The gap originally between the steps and the outside wall of the room is now gone, that is, the wall is butting against the steps. Also at that same end you can see the skirt for the room from bottom to top pointing outwards.
Thanks,
Pete
#13
It actually sound like your addition is racking..... moving towards out-of square..... or no longer perpendicular to the mobile home.
You would need to add cross corner bracing to stop that.

You can use a tape measure to check the diagonals. They should be the same if the addition is square.
You would need to add cross corner bracing to stop that.

You can use a tape measure to check the diagonals. They should be the same if the addition is square.
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racking
PjMax, yes, you are probably correct. This past summer I installed molding along the floors, cutting the ends of the molding meeting at the corners to 45 degrees. There ending up being a gap in the joint between sections of molding.
I'll see if I can measure diagonals.
Regards,
Pete
I'll see if I can measure diagonals.
Regards,
Pete
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racking?
Measuring inside the room, 5 inches above the floor, the difference of the diagonals is 1/2 inch.
Is this okay to measure inside the room? Underneath the floor is possible, but not very much fun and it would take longer to get the results.
Regards,
Pete
Is this okay to measure inside the room? Underneath the floor is possible, but not very much fun and it would take longer to get the results.
Regards,
Pete