I have a split-level house with an 8*12 m building area and an open floor plan. The living room is about 8 * 4 m (1/3 of the upper floor). The problem is that the ceiling is sagging. Starting from one wall of the room (the house's short outer wall), about 1 m out, the ceiling has sunk about 5 cm and hangs like that until it reaches the next wall/spindle 
. The sagging starts at the same distance out along the entire wall.
From my measurements, it's roughly where the second truss should be supporting the ceiling.
Someone said it's because the ceiling has detached, but when I removed a piece of ceiling board (a traditional ceiling with about 125 mm wide boards), it's flush against the upper "rough ceiling" made of grooved 75 mm wide boards. It seems strange, especially considering where the sagging starts.
Could it be too weak?
The house was built in 1974, and we moved in 1990, it was already sagging quite a bit then, but there were other renovations to do… Now we're considering whitewashing, which would make it more visible.
Someone at Cramo suggested trying to screw a strong board into the ceiling, perpendicular to the trusses, placing another on the floor, and then trying to wedge one in between the ceiling and the floor to lift the loose ceiling. If that doesn't work, the trusses might need lifting, for which Cramo had jacks for rent. I understood that with these jacks, with a crank that pushed the ceiling up, I should be able to lift the trusses' base so the ceiling becomes even (or slightly higher, I assume) and then better secure the trusses together.
What I'm wondering now is, how likely is it that this will work, that I won’t damage the trusses further, etc.?
The trusses in the attic seem to be made of an 8 m long beam 2" by 11” (maybe spliced, with 40 cm of wood shavings on top). The rafters are made of double 1" by 11" boards. Six 2" by 5" boards of various lengths hold the truss together (at the bottom, a 1" by 5" board binds on each side of the 2" by 5" board and the 2" by 11" beam, and upwards, a 2" by 5" is between the 1" by 11" rafters). Hmm, a lot of dimensions there, I can post a drawing of it if anyone wonders.
. The sagging starts at the same distance out along the entire wall.From my measurements, it's roughly where the second truss should be supporting the ceiling.
Someone said it's because the ceiling has detached, but when I removed a piece of ceiling board (a traditional ceiling with about 125 mm wide boards), it's flush against the upper "rough ceiling" made of grooved 75 mm wide boards. It seems strange, especially considering where the sagging starts.
Could it be too weak?
The house was built in 1974, and we moved in 1990, it was already sagging quite a bit then, but there were other renovations to do… Now we're considering whitewashing, which would make it more visible.
Someone at Cramo suggested trying to screw a strong board into the ceiling, perpendicular to the trusses, placing another on the floor, and then trying to wedge one in between the ceiling and the floor to lift the loose ceiling. If that doesn't work, the trusses might need lifting, for which Cramo had jacks for rent. I understood that with these jacks, with a crank that pushed the ceiling up, I should be able to lift the trusses' base so the ceiling becomes even (or slightly higher, I assume) and then better secure the trusses together.
What I'm wondering now is, how likely is it that this will work, that I won’t damage the trusses further, etc.?
The trusses in the attic seem to be made of an 8 m long beam 2" by 11” (maybe spliced, with 40 cm of wood shavings on top). The rafters are made of double 1" by 11" boards. Six 2" by 5" boards of various lengths hold the truss together (at the bottom, a 1" by 5" board binds on each side of the 2" by 5" board and the 2" by 11" beam, and upwards, a 2" by 5" is between the 1" by 11" rafters).
Hmm, a lot of dimensions there, I can post a drawing of it if anyone wonders.Hello!
The upper part of the beams (closest to the roof) is sinking 2-3 cm in the middle, I can see it in the attic.
Had a skilled carpenter come by. I had my doubts about the rafters, and he had never seen such a construction! Instead of one brace per side, forming three triangles, and each of the two braces supporting the bottom beam, plus two supports per side, it seems to be three supports per side...
Of course, it doesn't fit as it should! In almost every room in the house, it sags a little, but most visibly in the living room, of course.
So I guess I just "have" to lift the roof. Just need to check that it is at least attached at the peaks of the trusses. The house has built-in gutters (also a "feature" that I've had to redo to prevent the water from causing the boards to rot away, replaced boards and put on sheet metal). Is there anything I should consider when lifting and fastening the "rafters" to the trusses?
Best regards,
Stefan
The upper part of the beams (closest to the roof) is sinking 2-3 cm in the middle, I can see it in the attic.
Had a skilled carpenter come by. I had my doubts about the rafters, and he had never seen such a construction! Instead of one brace per side, forming three triangles, and each of the two braces supporting the bottom beam, plus two supports per side, it seems to be three supports per side...
Of course, it doesn't fit as it should! In almost every room in the house, it sags a little, but most visibly in the living room, of course
.So I guess I just "have" to lift the roof. Just need to check that it is at least attached at the peaks of the trusses. The house has built-in gutters (also a "feature" that I've had to redo to prevent the water from causing the boards to rot away, replaced boards and put on sheet metal). Is there anything I should consider when lifting and fastening the "rafters" to the trusses?
Best regards,
Stefan
