DIY Roof Frame

Prepare for truss framing by marking truss locations on both outside walls, marking one wall at a time. Start at the back of one wall, working on a ladder. Measure 1 1/2 inches in and draw a line across the cap board using a speed square, for the inside line of the first truss.

Measure 23 1/4 inches in and draw another line, the outside of the second truss. Add a line 1 1/2 inches farther for the inside edge of the second truss. Measure 24 inches and mark the outside line of the third truss, then mark the 1 1/2-inch inside line. Continue down the wall, marking truss locations every 24 inches. Repeat that on the other wall; make sure marks are identical on both wall caps.

Identify an end truss; manufacturers provide two, with more vertical bracing than interior trusses. Lift that truss to the roof upside down, with workers on ladders or scaffolds, or with workers outside the walls holding the truss and lifting it with poles notched on the end to hold the truss members. Have workers on the roof set that truss upright and fasten it to both wall caps with three framing nails, driven diagonally through the truss chord into the wall cap with a hammer. Put two nails on one side, one on the other.

Plumb that truss with a level and brace it with 2-by-4-inch boards nailed to the truss and to stakes in the ground beyond the end wall. Lift and erect a second truss and nail it to the wall caps. Set a third truss, check all three for plumb and brace them temporarily with purlins, 1-by-4-inch boards nailed across the outside truss members on both sides.

Work down the wall raising and setting trusses; brace with purlins every third truss. Double-check all trusses for plumb once all are in place. Add permanent bracing, depending on the design of the roof. Use purlins across the bottom chords, angled from the outside of the first truss to the center of the third. Put diagonal braces from the tops of the end trusses to the bottoms of the third truss. Use whatever bracing pattern is recommended by the architect or truss manufacturer.

Add truss and hurricane clips to all trusses. Put truss clips, L-shaped metal brackets that connect an internal top wall plate to the bottom chord of a truss, in every area where a truss chord rests on a wall plate. Install these with galvanized screws and a screw gun, 2 screws in each side of the clip. Nail hurricane clips to the truss ends and the outside wall caps with galvanized nails. Put one clip in each truss end with 4 nails in each clip, 2 into the wall caps and 2 into the truss chord.