Thanks buildright. Our house is an Edwardian style house rather than a traditional farm-style house. (I've been promptly corrected by my better half!!
) We are indeed looking for the traditional look on the inside of the house but that's a story for another day. As regards the stone, it is indeed natural stone we are using and not the fake stuff.
With the insulation boards, if both the 100mm board and 60mm board are installed back-to-back attached to the inner leaf of the cavity wall, what is considered the best method of 'tieing' both together? I think I've read somewhere that small cold-air currents can circulate between (1) the insulation boards if not secured tightly against each other and (2) if the inner board is not secured tight to the inner leaf wall.
With the sash widndows, the planning authority did not dictate this, it was our decision and we have seen these used on a similar style dwelling to ours and they really set it off. If it looks like we're living an another century then so be it! I am still considering using treble glazing on the north facing part of the house at least. Could you (or anyone else) recommend any reputable windows/doors suppliers? Thanks again for taking the time to respond.