However if you have a free standing pergola with a flat roof like mine you need to decide which way the grooves will go.
Putting a slope on a flat roof.
Measure from one top plate to the other across the roof in the direction that is perpendicular to the direction which you wish to line the peak of your new roof.
Include the overhang of the faceboards.
Currently water pools behind a large roof light so i wanted to raise the level of the roof felt so it flows to the edges of the roof light and away.
Which also determines which way the water will run off.
Hi i want to put a slope on a flat roof to ensure water flows from behind a roof light.
The second is to slope the roof trusses themselves this is done by the truss manufacturer.
Faceboards are the boards nailed to the ends of any exposed roof overhangs.
Inspect the roof structure for water and pest damage.
This solution is perfect for homeowners looking for the easy option for adding slope to a flat roof property.
Sunday august 5 2018 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.
The second is usually the easier and cheaper solution although the foam insulation adds some additional r value.
An example for a steep sloped roof is 8 12.
A flat roof is easily replaced by a one way slope or shed roof.
How to replace a flat roof with a sloped roof.
If your pergola roof has a slope or is attached to the house the direction of the panels is determined for you.
The structure does not need to.
Replace any rotten joists or plywood.
You will need to ensure that you are in standards with your local building codes and have the permits required.
The grooves need to point downhill and away from the house.
Flat roof slope the slope of a roof or pitch is determined by how many inches the roof rises over 1 foot or 12 inches.
The first is using tapered foam insulation on top of the roof trusses.
However in some cases building owners hire contractors that poorly designed the roof.
Most people view pitching a flat roof as a tedious job.
Eventually water penetrates the building.
There are two ways we typically use to create low slope on flat roofs.
Water that stays on a flat roof after it rains will weaken the material over time.
The flat roof already has a slight pitch as it is required by law.
Various styles of a pitched roof can be built or you can purchase pre manufactured trusses.
This means that the rise of the slope goes up or down 8 inches for every 12 inches.
Can metal roofing be used on a low slope pitch roof.
Using modern cement screed mixes a professional flat roofer can fill dips and hollows quickly and level them or slope them rather to fill the low point and re create the surface of your roof.