A benefit to doing it this way is that you can see if there is any rotten plywood that needs to be replaced before installing the new roof.
Installing metal roof over old metal roof.
Install the metal trim.
Install the roofing screws vertically along each rib in the panel.
Use notching scissors to notch the metal in the middle so that it will bend over the ridge.
Cool outside air then travels under the shingles to the vented ridge detail 2 pulling out moisture and heat.
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.
Be sure the larger edge is laid so that the small edge of the next panel will overlap it.
Your metal trim will go along the roof s edges as well as the top ridge.
1 remove the shingles before installing the metal roof the first way to install a metal roof over shingles is by completely removing the old shingles before installing the new metal roof.
Install drip edge drip edge or edge metal is a piece of metal that extends approximately 0 75 inch beyond the roof s edge to channel runoff into your gutters.
Should you tear off the old roof and start over or simply remove the fasteners from the existing roof and install another roof over it.
Venting the eaves to vent the roof holes are cut in the old roof above the soffit which pulls air through the soffit vents underneath.
Metal over metal retrofit considerations there are a number of issues a roofer will have to deal with when it comes to metal over metal retrofits but listed below are a few where the use of a roof hugger.
This is what it looks like when you install a steel shingle roof system over an existing asphalt shingle roof.
Pros and cons for metal roofing installation.
To install it slide the flat wide.
Metal roofing materials are available in several styles that require different fastening applications but are most commonly screwed to the roof framing or sheathing material which in the case of installing over existing roofing material should be fastened using 2 1 2 inch screws.
To vent the roof holes are cut in the old roof detail 1 above the soffit which pulls air through the soffit vents underneath.
March 11 2020 by safe harbor roofing reroofing is the practice that involves installing a new roof over an existing one.