I have a circa-1900 terraced house with a nice empty loft. There are no trusses running through the middle like in modern houses. Ignoring the wasted space under the eaves, the main section is about 3.5 by 6 meters (covering two bedrooms with a brick wall between) and there is another smaller connected part (maybe 3 by 4 meters) over the back of the house, which I am not so interested in right now.
I want to insulate and board most of the main section for storage, minus the eaves where it is too low to walk under.
I will add a loft ladder and more conveniently-sited hatch for access. I don't need a habitable room but I want the floor to be strong enough so Imelda Marcos can safely wander around putting things in and out of boxes.
At the moment it has some very tatty rockwool insulation between the joists which is (at least was originally) 100mm according to the bags which are left there with a few other random bits of wood and a few spare roof tiles. There is no water tank in the loft at the moment but there are a couple of power cables going over the joists. I have ferreted around up there, standing on the joists, and it seems relatively sturdy.
My initial thought was to put crossjoists at right angles to the joists, and screw some loft chipboard panels to the top of the counterjoists. Then I could have one layer of insulation between the joists and another between the counterjoists. The existing joists are 41 cm apart.
Since I want to be able to walk normally rather than the normal loft ferreting, should the counter joists be screwed into the brick walls? Should I then be thinking about steel and structural engineers or a proper joiner or something? Or is that complete overkill?
If the crossjoist idea is a goer, is there any particular size of timber I should use?
Can I put insulation between the rafters instead and would that simplify making a floor?
Thanks for reading.
I want to insulate and board most of the main section for storage, minus the eaves where it is too low to walk under.
I will add a loft ladder and more conveniently-sited hatch for access. I don't need a habitable room but I want the floor to be strong enough so Imelda Marcos can safely wander around putting things in and out of boxes.
At the moment it has some very tatty rockwool insulation between the joists which is (at least was originally) 100mm according to the bags which are left there with a few other random bits of wood and a few spare roof tiles. There is no water tank in the loft at the moment but there are a couple of power cables going over the joists. I have ferreted around up there, standing on the joists, and it seems relatively sturdy.
My initial thought was to put crossjoists at right angles to the joists, and screw some loft chipboard panels to the top of the counterjoists. Then I could have one layer of insulation between the joists and another between the counterjoists. The existing joists are 41 cm apart.
Since I want to be able to walk normally rather than the normal loft ferreting, should the counter joists be screwed into the brick walls? Should I then be thinking about steel and structural engineers or a proper joiner or something? Or is that complete overkill?
If the crossjoist idea is a goer, is there any particular size of timber I should use?
Can I put insulation between the rafters instead and would that simplify making a floor?
Thanks for reading.