I have 45x145 joists with cc30 and a free span of 2900 mm. Removed the previous floor, which was 18 mm particle board, nailed and poorly glued, and plan to replace it with new 22 mm floor particle board.
The lowest point in the room is found at the joist along the door to the room, others are a few millimeters to at most 10 mm higher on the middle joists. I want to level it preferably without raising the floor towards the adjacent rooms.
I was thinking of planing the unevenness and then reinforcing the joists with construction plywood glued and screwed to the sides, but the more I read about it, the more uncertain I become. It seems some say it works perfectly fine, while others say plywood doesn't add any significant strength.
Does anyone know how it stands? Does it work to reinforce with plywood? Adding new 145 joists would be tricky, an alternative is 120. Maybe it's entirely overkill to reinforce the existing joists, but I don't want to experience the reason I tore up the floor, which was bounce and creaking.
The lowest point in the room is found at the joist along the door to the room, others are a few millimeters to at most 10 mm higher on the middle joists. I want to level it preferably without raising the floor towards the adjacent rooms.
I was thinking of planing the unevenness and then reinforcing the joists with construction plywood glued and screwed to the sides, but the more I read about it, the more uncertain I become. It seems some say it works perfectly fine, while others say plywood doesn't add any significant strength.
Does anyone know how it stands? Does it work to reinforce with plywood? Adding new 145 joists would be tricky, an alternative is 120. Maybe it's entirely overkill to reinforce the existing joists, but I don't want to experience the reason I tore up the floor, which was bounce and creaking.
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Look at kertobalk part is stiffer than glulam and cheaper. But looks like f... so it shouldn't be visible.
Veneer laminated wood or LVL are panels or beams made by gluing thin layers of wood veneer. Unlike the more common plywood, the veneers in LVL are laid with the fibers in the same direction during manufacturing. This gives LVL completely different strength and shrinkage properties than plywood.
Veneer laminated wood or LVL are panels or beams made by gluing thin layers of wood veneer. Unlike the more common plywood, the veneers in LVL are laid with the fibers in the same direction during manufacturing. This gives LVL completely different strength and shrinkage properties than plywood.
Definitely sounds interesting but a bit more complicated to get hold of and in a different price range. The plan is to be able to walk on the floor after the weekendL Leif i Skåne said:Look at kertobalk part, it is stiffer than glulam beam and cheaper. But it looks like f… so it shouldn't be visible.
Veneer laminated wood or LVL are sheets or beams made by gluing thin layers of wood veneer. Unlike the more common plywood sheet, the veneer sheets in LVL production are laid with the fibers in the same direction. This gives LVL entirely different strength and shrinkage properties than plywood.
Best answer
First question: Is it an improvement or a deterioration in terms of stiffness to plane down 10 mm and reinforce with 12 mm screw-glued k-plywood on both sides? I am disregarding any differences in the modulus of elasticity. The moment of inertia for 45x145 is 1143 cm4, for 45x135 plus plywood 1415 cm4. So it is an improvement. With c/c 300 mm and screw-glued 22 mm chipboard, the flex will be OK.
Thank you very much for your response!J justusandersson said: