I have a loft conversion that was done eons ago and the upshot is that the joists need to be larger and supported adequatly.
I have what I think is called a cut roof so the rafters hang over beams down to the outside wall of the house and the joists for the loft are nailed to the rafters about three or so feet up each rafter from the outside wall and then span to an interior supporting wall. Currently, in the loft at each side of the house is a small false wall that is attached to one of the roof supporting beams (which is in effect supporting the loft joists). The joists are at these points 425mm below the bottom of these beams.
The idea that I have is to put in new larger joists adjacent to the current joists and suspend these from the roof beams. Is there a method of doing this? Does anyone have a better idea?
From your description it sounds like you have a collared roof with the collars forming the floor of the loft conversion. When this is done and the collars are not supported at their ends the walls of the house are pushed outwards.
You really need a structural surveyor to have a look at the problem and to give you advice.
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