Hello,
first post on the forum, have searched but not found an answer to my question so I'm taking the plunge and hope the answers here can also help others!
I have bought a more robust summer cottage from 1936 with a loft and want to raise the ceiling height on part of the ground floor. The house was built in 1936 with vertical plank walls. The dimensions are about 7x11 m, internal ceiling height 2.60.
The roof trusses are framework trusses cc 100 with collar tie and an intermediate floor cc 600. Roof slope 30 degrees, metal roof, snow zone 2.
Dimension on roof trusses and floor is 75x170. The intermediate floor is not nailed to the roof trusses but is joined with two nails over a plank wall in the middle of the house.
In half of the house, I simply want to remove the intermediate floor and the plank heart wall to create a large airy room, open to the underside of the collar tie. There is then about 1 m remaining between the ridge and the underside of the collar tie.
The span would then be about 7m over a 5m long stretch.
An experienced builder says it should suffice to reinforce the roof trusses with screw-glued 12mm p30 plywood as a triangle down to the collar tie on both sides and to fit reinforced 105 angles with anchor screws between the truss and wall plate. This would prevent the walls from being pushed out when the intermediate floor disappears.
Does this seem reasonable? The truss construction is not changed but reinforced, the span is fairly moderate. The plywood triangle would be quite large, and the floor is, as mentioned, barely nailed in the rest of the house...
Thanks in advance!
/Viktor
