Graham Trotter
Hello Pete, I would suggest that you would need drawings for the extension,you can build the extension out of blocks and render the blocks,you would probably require a 100mm cavity.if you were to have part of the structure glass then a good architect will be able to design this for you.You will definately need building regs,and if your knocking through you would need planning.Cost wise i would allow a budget of between £22500 and £26000 depending on what spec you have internally.
