With regards to the pitch the building standard code bs 5534 recommends a minimum pitch of 200 for slate roofs.
Good roof grade.
Roof slope expressed as rise run in inches.
Simply put pitch is expressed as rise over run just as the grade is simply this fraction expressed as a percentage.
0 or 180 0.
There are advantages and disadvantages to having a steep pitch versus a shallow or low pitch.
And it weighs about the same as asphalt so there s no need to beef up the.
Roofs are framed with rafters or trusses which are rafters joined by internal braces so they install as a single component.
Asphalt shingles are easy to install last anywhere from 10 to 50.
3 12 1.
Asphalt shingles wood shingles and shakes metal roofing concrete clay and fiber cement tiles natural and.
A roof slope of 7 12 is also good and can provide the additional benefit of helping minimize the effects of wind driven rain.
This composite material looks like the real thing even close up but costs a lot less.
The minimum plywood for roofing.
0 12.
However from the wind uplift mitigation perspective a 7 12 roof slope can be considered as a two story building due to the higher overall steepness and profile of the roof.
In this guide we ll cover the following most common roofing options.
Common roof slopes expressed in rise run and angle slope expressed as grade.
For cr s roofing tests we focus strictly on asphalt roofing shingles because they re by far the most common choice for roofs.
Pitches lower than 4 12 have a slight angle and they are defined as low slope roofs.
4 76 8 33 grade.
Easy to walk on.
But since there is still a wide variety of slate roofing systems there are occasions when the minimum pitch can go down to as low as 15 0 depending on the uniqueness of the roof.
Steel copper and zinc also carry their pros and cons.
A 4 12 pitch being 4 inches of vertical rise over one foot or 12 inches of horizontal run.
Roof slope expressed as an angle.
Copper roofing pros cons the grandfather of metal roofing copper roofing has been used for centuries around the world.
The most commonly used roof pitches fall in a range between 4 12 and 9 12.
Pitches above 9 12 are very highly angled and are designated steep slope roofs.
Pitches of less than 2 12 are considered flat roofs even though they may be very slightly angled.
While an aluminum roof is an excellent option for resisting rust in salty regions it s durability factor can be much lower than other materials.