Figure height of support for sloped roof

[Yod12]

I'm making a shed for my generator Using 2x2s, I made bottom frame, cut four posts at 10 degree angle which are verticle supports. I need to figure new height of two posts to support roof. This is quick sketch. I painted and sealed all members and connected bottom structure with strong ties, so at this point I'm committed to this design

 

[Snoonyb]

And the dimensions are?

 

[Yod12]

I saw a reference to a formula that would calculate what the height of sloping supports should be based on the dimensions, no matter what those are. That was it, just a reference that led nowhere. I ended up eyeballing it and luckily it turned out perfect.

 

[Snoonyb]

Any framer will tell you that roof slope is measured in degrees, IE, you select the roof slope, set your compass, draw the line, measure from the line to the ground, AT THE DIMENSION, you want the support at, and bingo.

 

[nealtw]

Framers use the rise over run like 2/12 or 16/12, never look at degrees.

 

[Snoonyb]

I guess that's why I know that a 4:12 pitch is 18-1/2 degrees, or for that matter, any roof pitch.

 

[nealtw]

That is what gets guys in trouble.

Roof Pitch Degree Table
1-12	4.76°
2-12	9.46°
3-12	14.04°
4-12	18.43°
5-12	22.62°
6-12	26.57°
7-12	30.26°
8-12	33.69°
9-12	36.87°
10-12	39.81°
11-12	42.51°
12-12	45°

This is our pitch calculator which will convert pitch to angle or angle to pitch for half degree roof slope calculations. Enter any pitch or fraction of pitch to find angle. Enter any angle or fraction of angle to find pitch.

Roof Pitch Interactive Tools
Pitch	---->	Angle
Building Run FEET INCH	Building Rise FEET INCH		Pitch

 

[Snoonyb]

It's so simple to measure the height of the support, when you've established the slope.

 

[68bucks]

Trigonometry

 

[bud16415]

Much of our building trade goes back 500 years or more. Feet and Inches/fractions, Pitch, How many Penny nail we use. It is completely logical to someone that has grown up with it, but in today’s computer world of CAD it is all a PITA.



Not sure what the metric countries do about pitch?

Speaking of trig I have a couple handy free trig apps on my phone. It is hard to believe when I started my work life one of my most prized possessions were my leather bound trig table book. The other was my slide rule. I wonder what percentage of kids leaving high school or even collage now can extract a square root of a number with paper and pencil? Let alone do long division.

 

[nealtw]

How to you use a square. We work with the pitch on the plans

https://inspectapedia.com/roof/Framing_Square_Table_Use.php