Roof Ridge Board Thickness

The ridge board s length will be the outside measurement of the building plus the length of the overhang at both ends.

Roof ridge board thickness.

There are several variables to consider when determining the proper rafter size. Ridge boards can only be used in roofs with slopes from 3 in 12 up to 12 in 12. You may splice two boards together to achieve this length if necessary using a 14 and 1 2 inch block of the same material. Weather you re building a shed roof or adding a dormer to your second story it is important to choose the proper size rafter.

As a reminder please don t forget to add height of rafter thickness of roofing material and ridge vent to the number that you ll get using our calculator. Roof pitch between 15 and 22 5 degrees with rafter spacing strength class c16 size of rafters in mm 400mm 450mm 600mm. For 2 x 4 rafters use a 2 x 6 ridge board. For 2 x 6 rafters use a 2 x 8 ridge board and so on.

This sizing guide for roof rafters will help determine what you need for your small project. Oriented strand board osb or plywood can be used although plywood will provide higher nail head pull through resistance. Ridge boards shall be at least 1 inch nominal thickness and not less in depth than the cut end of the rafter irc section r802 3.