i want to put down a new floor in my loft, after removing an old brittle chipboard one. my loft is 1904 end terrace and is supported with purlins in the center of each pitched roof plane ( although these are not sunk into the party wall or end gable wall) with supports running from them to the center load bearing wall in a v formation. three v's in all. one at each end and a central v.
the 4"x2" cieling joists run front to back joining over the center wall. the joists are aprox 12ft from back to center, and 13ft from front to center. these are slightly higher in the center over the wall and slope away to each external wall.
i want to floor this to store some heavy ish stuff, my record collection which is huge, and some speakers etc...
what i want to know is, does running a 2"x2" along each joist to raise and level the floor add more strenght than running the battens crossways to form a grid, or the other way round.
on the first method i would screw the 2"x2" battens along the joists every foot, effectivly adding 2 inches to the top of each joist, and would then screw down the 8'x2' 18mm ply over this at right angles to the joists, giving a solid platform.
however, due to the rafters dropping onto a 2"x2" beam, which sits on top of the ends of all of the cieling joists, (which in turn sits on top of the external load bearing walls, front and back), i cannot run the new battens onto the load bearing wall at either end, so they would, in effect, only be screwed to the top of each rafter just shy of the load bearing walls at each end, and would only be supported by a load bearing wall in the center of the loft space..
the other method, to fix the battens crossways ontop of the joists, would mean less points of contact over each joist, being only at the intersections between the joist and batten. this would be screwed and then the 8'x2' 18mm ply floor screwed to the crossbattening to form a solid platform. these crossbattens would not be over any load bearing walls as they would run parrellel to all three load bearing walls and would not be attached at either end to the party wall, or the end gable(?) wall with chimney.
i would also be interested to know if raising the cieling joists by 2" with battening would add more strenghth than if i just floored the joists as they are..
i am also thinking of removing the purlins central pair of 'v' shaped bracing (from mid way up the pitch on each roof plane, to the central load bearing wall), and instead bracing across the apex of the rafters and running triangulations from the centre of the purlins to the party wall and end gable at cieling level, with additional 2"x2"vertical supports dropping to a horizontal beam 6"x2" running from party wall to end gable, ontop of the cieling joists, supported at each end by joist hangers bolted to the walls. this would give me space to move around and open up the area. if i brace each end of the purlins to the end walls with heavy duty bracketing also then will this be enough support to remove the 'v' shaped central support. any help would be really helpful . thanks.
the 4"x2" cieling joists run front to back joining over the center wall. the joists are aprox 12ft from back to center, and 13ft from front to center. these are slightly higher in the center over the wall and slope away to each external wall.
i want to floor this to store some heavy ish stuff, my record collection which is huge, and some speakers etc...
what i want to know is, does running a 2"x2" along each joist to raise and level the floor add more strenght than running the battens crossways to form a grid, or the other way round.
on the first method i would screw the 2"x2" battens along the joists every foot, effectivly adding 2 inches to the top of each joist, and would then screw down the 8'x2' 18mm ply over this at right angles to the joists, giving a solid platform.
however, due to the rafters dropping onto a 2"x2" beam, which sits on top of the ends of all of the cieling joists, (which in turn sits on top of the external load bearing walls, front and back), i cannot run the new battens onto the load bearing wall at either end, so they would, in effect, only be screwed to the top of each rafter just shy of the load bearing walls at each end, and would only be supported by a load bearing wall in the center of the loft space..
the other method, to fix the battens crossways ontop of the joists, would mean less points of contact over each joist, being only at the intersections between the joist and batten. this would be screwed and then the 8'x2' 18mm ply floor screwed to the crossbattening to form a solid platform. these crossbattens would not be over any load bearing walls as they would run parrellel to all three load bearing walls and would not be attached at either end to the party wall, or the end gable(?) wall with chimney.
i would also be interested to know if raising the cieling joists by 2" with battening would add more strenghth than if i just floored the joists as they are..
i am also thinking of removing the purlins central pair of 'v' shaped bracing (from mid way up the pitch on each roof plane, to the central load bearing wall), and instead bracing across the apex of the rafters and running triangulations from the centre of the purlins to the party wall and end gable at cieling level, with additional 2"x2"vertical supports dropping to a horizontal beam 6"x2" running from party wall to end gable, ontop of the cieling joists, supported at each end by joist hangers bolted to the walls. this would give me space to move around and open up the area. if i brace each end of the purlins to the end walls with heavy duty bracketing also then will this be enough support to remove the 'v' shaped central support. any help would be really helpful . thanks.
