RAFTER SPACING FOR METAL ROOF ON LEAN CRACK

(basically take a hole saw, saw in about 1/2 inch, and put about a 7/8 inch long section of pipe/like in that hole saw cut). This way your rafter span will be about 6' at the most. I also like to set the posts so that there would be approx a 2' cantilever (overhang) and also bring the end posts in about 1' from the perimeter as well.

RAFTER SPACING FOR METAL ROOF ON LEAN CRACK

Note also that you can break up the span of a rafter. I would suggest using 3 - 6 x 6 posts as they won't crack and twist as easily as a 4 x 4. The wider the space between rafters often results in rafters of greater depth too. Depending on all contributing factors though, 16 and 24 are commonly used for most buildings.

Not saying your not pushing the modern limits of construction, but if you have enough 2圆's one could double up a few one on each side of the existing rafter, or as far as shear, if your concerned, could consider a split ring type of attachment, When calculating the maximum span of a rafter, use the horizontal distance between two vertical supports. Standard industry roof rafter spacing is 12, 16, 19.2, and 24 on-center, however other spacing may be used by a Structural Engineer. I have buildings with 2x4 on 24 spanning 12 foot, slight sag after 90 years,Īnother building 2x4 24 on center spanning 10', no seeable sag, 70 years,īarn lean to sheds, 2圆 24 oc, 15 foot, span slight sag it is 105 years old, (all lumber is Douglas fir)Īll have approximately the same slope as your drawing, all of my buildings are 1x sheeted and have been shingled, with asphalt shingles, the barn is sheeted but tinned now,

Rafter spacing for metal roof on lean