Pythagorean Theorem Roof Framing

Specialized terms help to explain the triangle relationships in roof construction.

Pythagorean theorem roof framing.

Roof framing is all about right triangles but the pythagorean theorem is not widely used in calculating the lengths of the roof framing members and calculators use trigonometric ratios to calculate the lengths of the right triangles not the pythagorean theorem. Stick built rafter steps. A2 x b2 c2 your rafter length 14400 20736 35136 the square root of which 187 446 your rafter length in inches step 2 lay out your rafter. The pythagorean theorem is used extensively in designing and building structures especially roofs.

I haven t used the pythagorean theorem since the 1970 s as a apprentice carpenter to calculate rafter lengths. Then add the length of the rafter tail. Use the pythagorean theorem to calculate the rafter length. Pythagorean formula c 2 a 2 b 2 where a b are the legs of a right triangle and c is the hypotenuse.

Apr 9 2015 the pythagorean theorem makes carpentry work so much easier when it is used for squaring walls foundations and roof framing. The height of the roof above the ceiling is 13 5 ft and the roof is 36 ft across as shown in the figure. Gable roofs for example are made by placing two right triangles together. Align your framing square so the 10 mark and 12 mark meet the edge of your rafter stock.

Geometry section 17 1 planning a roof 467. Pitch whether using roof trusses or stick building the roof the pitch of the roof must be selected.