When the building is square and plumb, the next step is to install the rafters. After this step is completed, your granny flat will be structurally sound and solid.
Slotting rafters into place
Assemble the rafters according to the drawings of your granny flat. All boards are marked, so make sure you have rafters located correctly. Bang each and every rafter into place all the way down. Rafters and walls have to be flush for the ceiling boards installation.
Experts Tip #1: Depending on a model, one rafter can weigh about 100 kg! So, for better use of labor, hire a truck with hiab for an hour or two. Machinery will help the team greatly keeping the energy going for the final building steps.
When all rafters are in, screw them at all junctions interlocking with the walls. Screw comes from the outside of the facing of the timber and goes right through to the top wall-boards.
Experts Tip #2: “Have your screws long enough to go on angle through the rafter into the top wall-board piece. This way screws hold the the batten very secure also stops any movement.”
When the rafters are all in and secured you have the building structurally sound and solid. The next step is installing an overhang above veranda. All granny flat building steps can be found on Builders Guide page.