Roof Ridge Board Thickness

This sizing guide for roof rafters will help determine what you need for your small project.

Roof ridge board thickness.

Use panels rated as exposure 1 or better. 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. You may splice two boards together to achieve this length if necessary using a 14 and 1 2 inch block of the same material.

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. 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. For 2 x 6 rafters use a 2 x 8 ridge board and so on.

There are several variables to consider when determining the proper rafter size. The ridge board s length will be the outside measurement of the building plus the length of the overhang at both ends. Typically 15 32 inch or thicker panels are required in high wind areas.