The pitch is measured in inches of vertical rise per foot of horizontal run and the 5v crimp profile shown above requires a minimum slope of three in twelve or 3 12 3 inches vertically per 12 inches horizontally.
Minimum pitch for corrugated roof sheets according to building regilations.
The cladding should be supported at maximum centres as specified by the manufacturer and fixings should be a minimum of 50mm from sheet ends.
When it comes to thatch roofs generally the slope should be 45 degrees except at dormer windows where the slope should only be 35 degrees.
According to the 2012 international building code 1507 4 2 deck slope minimum slopes for roof panels need to comply with the following.
The most common evil performed by so called roofers is the use of corrugated roofing all the manufacturers nominate a 5 degree minimum pitch for this profile whenever and wherever a metal roof is called for.
According to this code the minimum slope for asphalt shingles is 17 degrees or two vertical units to twelve units in the horizontal.
For example a roof that rises 3 inches for every 12 inches has a pitch of 3 12.
The traditional metal roof types such as 5v crimp shown above and corrugated are rated by the manufacturers for use down to a 3 12 pitch three inches of vertical rise for every foot of horizontal run.
Clay and concrete tile requires a minimum roof pitch of 2 1 2 12 or greater.
Pitch roof this is where tiles or slates are used and a void is usually created underneath.
In addition to maximum spans there are also minimum requirements in terms of slope or pitch and minimum end laps.
Corrugated metal roofing has the same minimum pitch.
Asphalt shingles require a minimum roof pitch of 2 12 or greater.
The requirements for an asphalt shingles roof are contained in the international building code.
Let us recap on the minimum roof pitch required for each type of roofing material.
I have a closet full of stories about flat corrugated roofs that leak.
To enable compliance with the requirements of the building regulations to be demonstrated full details of the new roof will be needed including.
Flat roof this usually consists of felting which has a slight fall to allow rain water to drain off.
Metal roof shingles require a minimum roof pitch of 3 12 or greater.