I am about to commence the building of a double extension at the side of my property, the question I have is what is the correct size RSJ my builder will require. They will be knocking down the outside wall at the side, creating a through room to the side of the house.
The opening will be approximately 10 feet, the room above will be the bathroom and that wall will also be removed to extend. The roof will be pitched so this wall will no longer support that.
I am sure my builder is fully qualified but just wanted to check to be sure. I have tried all of the websites but they are confusing to work out, and are based on a sale rather than calculation.