When building a roof, there are four primary steps. The first step is to cut the trusses and put them in place. Then you will lay the material on top of the frame. The next step is to install the roof sheathing. Once this is in place, you will attach the underlayment and cover your roof. The final step is to hang the shingles. After the cover is installed, the roof will be secure and protected from the elements.
To build the rafters, you will need timber, galvanized steel truss plates, hammer, nails, and 1/2 inch galvanized screws. You will also need a saw. Depending on the weight of the roof, you will need to cut the timber to the desired thickness. The most common sizes are 2 x 6 and 2 x 8 timbers. You will also need galvanized steel connector plates to hold the timber together.
Before constructing the roof, you must ensure that the walls are level and square. To do this, you will need to use wedges to make sure the walls are level. After that, you will want to place wall plates onto the walls. Anchorage devices will secure the wall plates to the walls. Once the wall plates are in place, you can begin putting the roof on top. The ridge piece is installed over the center of the gable walls, and is level with the wall plates. The ridge piece is then fixed to the ridge beam. The height of the teepee depends on the pitch that you want for your roof. To determine how high you need to fix the teepee, check out Appendix 1.
Once the walls have been installed, you can start the roof assembly. You should check that the rafters are aligned and at right angles. If there are gaps, you can fill them with mortar and then attach the wall plates to the walls with anchorage devices. Once the walls are ready, you can fix the ridge beam over the center. The height is determined by the pitch you are looking for. You can consult a table in Appendix 1 for the height required.
Next, you must place the loft floor joists. The joists are attached to the wall plates and then skew-nailed into place. Then you will screw the ridge tiles into place. You will need to use the ridge-to-ridge seal to keep the rafters in place. When assembling the roof, you will need to fix the rafters on top of the joists.
Next, you need to install the loft floor joists. These joists are fixed into place with a skew-nailed system, and screwed to the central spine wall. The ridge jibs provide the working platform for the roof assembly. They will resist the forces applied by the rafters during the roof assembly. The ridge jibs must be level and the roof trusses must be level.