Roof Ridge Board Thickness

Use panels rated as exposure 1 or better.

Roof ridge board thickness.

Roof pitch between 15 and 22 5 degrees with rafter spacing strength class c16 size of rafters in mm 400mm 450mm 600mm. Oriented strand board osb or plywood can be used although plywood will provide higher nail head pull through resistance. This sizing guide for roof rafters will help determine what you need for your small project. For 2 x 4 rafters use a 2 x 6 ridge board.

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. There are several variables to consider when determining the proper rafter size. If your goal is to only calculate the roof height do not enter any numbers in wall height field and only use building width and roof pitch fields. The ridge board s length will be the outside measurement of the building plus the length of the overhang at both ends.

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. Ridge boards can only be used in roofs with slopes from 3 in 12 up to 12 in 12. Typically 15 32 inch or thicker panels are required in high wind areas.