I've attached a sketch of what I did, it had to be done as cheap as possible and I if it came to selling I would accept I couldn't advertise as a room. I did the majority of the work apart from skimming the plasterboard and it cost less than £2k for everything.
I had quite limited headroom so had to design it to keep it as high as possible - to make it a worthwhile room would have involved dropping the ceiling at first floor level which I wasn't prepared to do (the neighbours did)
Thanks, that's really helpful! I'm thinking of something along the same lines (limited headroom, dropping ceiling + dormer was too expensive). Had been wondering if beams between party walls was legit, time to get the measure out!
I bought two 250x75 (I think) bolted them together and fixed to heavy duty joist hangers. I also had them put into the attic when I had the roof off to be re-roofed.
If I was doing it again I would probably use steel beams onto padstones built into the wall - however its not fallen down yet...
I've attached a sketch of what I did, it had to be done as cheap as possible and I if it came to selling I would accept I couldn't advertise as a room. I did the majority of the work apart from skimming the plasterboard and it cost less than £2k for everything.
I had quite limited headroom so had to design it to keep it as high as possible - to make it a worthwhile room would have involved dropping the ceiling at first floor level which I wasn't prepared to do (the neighbours did)