Measure 4 total pieces of 5 inches 1 3 cm thick osb or plywood.
How to measure for a gambrel roof for steel.
For a barn style gambrel roof you will need flashing at the top and the 2 middle points where the roof slopes meet.
Find out how wide each piece of metal is then divide the width of the roof by that number.
For instance a 38 panel will have an effective coverage width of 36.
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To calculate a gambrel roof select gambrel roof from the roof type dropdown list or click on the appropriate toolbar button to calculate a gambrel roof.
How to put a metal roof on a gambrel roof.
Gambrel roof framing geometry calculator inch this gambrel roof fits in a semicircle and starts as the top half of an equal sided octagon.
Draw a semi circle on the graph paper mark a center peak at the top and draw two lines on each side in the shape desired for the gambrel roof.
Replace any sections of damaged decking using material of a similar thickness and type.
Enter the diameter of the roof ridge vent gap 1 3 finally enter the coverage area width of the panels you plan to buy.
Check overhang to calculate rafter overhang equal to the lower level cut at the full rafter depth.
Tear off any old roofing down to the decking.
Start at one lower corner along the gambrel end.
These pieces should be half the length of your structure and the width of each piece of your rafter.
Measure and cut osb or plywood for the roof sheeting.
Calculate gambrel angles with graph paper and a protractor.
For example what we need on the picture of the roofs below are measurements of all the blue or red lines.
Here at 1st coast metal roofing supply we value our customer service and product q.
So for example if your barn is 10 by 12 feet 3 0 m 3 7 m each piece of osb should be 6 by 3 83 feet 1 83 m 1 17 m.
The preview drawing displays a dimensioned elevation view of the gambrel roof.
Move slider or directly enter angle to alter sweep angle of lower rafters and change the shape.
Use the protractor to measure those angles at the peak the walls and the point where the two lines intersect on the top side of the roof.
Install the first sheet with one long edge.
Roughly draw out your roof on a piece of paper.
The metal roof length calculator calculates the distance from peak to trim so add the length you want the roof metal to extend beyond the eave trim.