One downside is that the metal sheets have a susceptibility to denting both in installation and during hailstorms.
How to install metal roofing on plywood.
Inspect the plywood for damaged areas.
Add the metal panels.
As long as the plywood under the shingle roof is in good condition this way can provide many benefits.
To secure it measure it roll it out over the plywood cut it to the dimensions of the roof with a roofing or utility knife and finally hammer it securely to the plywood with 1 2 inch roofing nails.
Repair any rotted sections of plywood before installing the metal panels.
I was planning on putting plywood over the rafters and cross the rafters with a 2 x4 every 16 to secure the metal roof to.
Install the roofing screws vertically along each rib in the panel.
Always begin working at the point with the longest peak to eave distance.
But it seems the condensation will affect the 2x4 strapping.
You will use metal roofing screws to secure the metal panels to the sheathing.
Sweep the plywood clean of all dirt and.
This is by far the most common way to install a metal roof.
Take your first sheet of.
And for any exposed fasteners try to avoid over tightening them.
Try to space the screws about 12 inches apart down the entire piece of metal.
3 install 1x4 purlins down over the shingles before installing the metal roof the third way to install a metal roof over shingles is by applying 1x4 purlins over the shingle roof.
In this installation the vapor barrier is installed on the side of the insulation nearest the interior of the building.
Remove all unused vents pipes and protrusions.
Be sure the larger edge is laid so that the small edge of the next panel will overlap it.
Metal roofing resists rot is not susceptible to insect damage and is non combustible a boon in fire prone areas.
Hammer down all raised nails.
In reading online it seems wise to install a vapor barrier over the plywood to prevent condensation from getting adsorbed into the plywood from the steel roof.
When using plywood nail it directly to the purlins and screw the metal roofing panels through the plywood into the purlins as instructed by the manufacturer.
The edging or eave flashing consists of metal strips that are used to cover the perimeter of the roof.
Moreover try to ensure that the screws are all aligned evenly.
Align the first metal roofing panel so that it overlaps the edging by 1 2 to 3 4 of an inch and is square to the roof line.
Use your 1 1 4.