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cowchuk
Mar 29, 2010, 06:36 PM
Im building a garage its on a 2 foot grade beam and has a ten foot wall so that's 12 feet in total it is 24 feet wide and 32 feet long. My question is approx what pitch I need on the roof to come in at under 18 feet from ground to peak as that's what I am limited to bye restrictions in the city were I live any help would be appreciated.

cowchuk
Mar 29, 2010, 08:25 PM
Come on someone help me please I need to figure this out quick.

hkstroud
Mar 29, 2010, 08:39 PM
height limit 18'
Wall height 12'
...
height of roof 6'

width 24/2=12



Total rise 6'
Total run 12'

For every foot of horizontal travel there must be a 6" rise.

Pitch is 6" in 12".

That is a pretty steep roof (45 degrees). Can be less. Depends on snow load, type of construction, trusses or stick built rafters and joist, and size of rafters.

cowchuk
Mar 29, 2010, 08:52 PM
So that would be a 6/12 pitch then am I right on this. So a 4/12 pitch would be higher than this or lower I am just trying to picture this what do I need to tell my supplier when ordering so I end up with the proper trusses.

hkstroud
Mar 29, 2010, 09:12 PM
A 4/12 pitch would be lower.

For ever 1 foot of run there will be 4" of rise. That would 4"x12 ft or 48" or 4 ft total height. 6/12 would be 6"x12 or72" or 6 ft total height.

hkstroud
Mar 29, 2010, 09:18 PM
Error on my part, 6/12 will be a 22.5 degree angle not 45. A 12/12 would be 45 degrees.

creahands
Mar 29, 2010, 09:57 PM
If u use a 6/12 pitch, u will be right at 18'. If your measurment is a little off, u could be over height restriction.

Recommend use a 4/12 pitch and u will be well below max height.

Good luck

Chuck

cowchuk
Mar 30, 2010, 03:50 PM
Thanks you guys are great I figured everything out my trusses are 4/12 so 12+4 = 16 wich in turn equals a happy city inspector. I live in yorkton sask and our codes for a detached garage/shop in the city is a limit of 800 square feet and a ground to peak height of 17.5 feet unless its attached to the house then you can build it as big as you want how does this fit in with other peoples local by laws.

manhattan42
Apr 2, 2010, 07:45 AM
18 Feet is an fairly common maximum height restriction for a detached accessory building.

How that height is measured is not so common, however.

Some municipal codes require the height to be measured from the lowest point above grade to the highest point above grade. If you have garage built into a slope under this scenario, you could have a 16 foot high 'walk-out' wall on the downhill side of the slope but only 2 feet above grade showing on the uphill side.

Other municipal codes take an average of all heights above grade to determine the actual height.

Using this method, you could potentially build a 2-story garage into a slope by having an 18 foot high walk out wall on the downhill side but still have 18 feet exposed above grade on the uphill side... because the average height of the structure above grade will still only be a total of 18 feet.