New zealand metal roofing manufacturers inc.
Minimum roof pitch nz.
They provide excellent weather resistance great value and now more than ever a tremendous range of beautiful designs and color blends.
Although it can be laid on roof slopes as low as 8 12 15 minimum pitch is more typically recommended and sheet end joints must be sealed.
The short simple answer is 2 12 has traditionally been considered the absolute minimum acceptable roof slope suitable for asphalt shingles.
The following tableprovides the minimum required allowable roof slope for each type of roofing material mentioned in the code.
It is corrosion and fume resistant econom ical requires only simple tools for fixing and its flexibility and light weight gives planning and design freedom over many other roofing materials.
However it is regrettable that many installers usually ignore this requirement due to the desire for a quick installation process.
Raising the minimum roof pitch of all coated steel and aluminium products gives enough tolerance to avoid roof deterioration and ensure the roof dries meeting the minimum 15 year durability requirement of the nzbc.
When a combination of sheets provide a run of in excess of 40 metres and up to 60 metres the roof pitch should be increased by 1 degree.
Minimum roof cladding pitch 4 8 2.
Longer lengths require specific design.
Downpipe for catchment over 50 m.
Roofing horizontally and vertically laid cladding.
What is the minimum slope for an asphalt shingle roof.
Asphalt shingles continue to be the most widely installed roof covering option in north america.
Minimum pitch the minimum roof pitch for corrugate is 8 degrees approx 1 7 and if end lapped 10 degrees approx 1 6.
Auckland whangarei hamilton tauranga palmerston north new plymouth hastings wellington christchurch cromwell.
The nz metal roof and wall cladding code of practice also recommends increasing the minimum depth of the valley gutter to 75 mm where the roof pitch is between 8 12.
The minimum roof slope allowed by code for any type of roofis in 12 applicable only to coal tar pitch roof systems.
However after seeing issues of water ponding as roofs settle over time the metal roofing industry changed this in the 1970 s to a minimum pitch of 3 for all coated steel and aluminium products.
