Putting Metal Roofing Over Old Roofing

Some roofers recommend this practice to homeowners who are planning on switching from an asphalt shingle roof.

Putting metal roofing over old roofing.

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. Doesn t provide the flattest surface for the metal roofing to be installed over each course of shingles is about a 1 8 higher than the course just below it. The installation of metal roofing is often easier and faster than other roof types and because of its simple design and generally large size can actually be installed directly on top of existing roofing materials like asphalt shingles and foam roofing. To vent the roof holes are cut in the old roof detail 1 above the soffit which pulls air through the soffit vents underneath.

But is this a good idea. By removing the old roof before the new roof s installation you are able to give the underlayment a thorough inspection to ensure there are no damages that could. Installing a metal roof over shingles can also result in an increased chance of trapped water vapor and moisture between the new roof and old roof resulting in new mold and rot. 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.

Installing a new roof over an existing one also called a layover or nailover is often possible although not always the best option a properly installed layover roof can look and function as well. Installing metal roofing over existing roofing material can usually be successfully. However installing new flashings including special drip edge flashings made for reroofing will ensure a tight seal and a long life. Some roofers install a layer of waterproof shingle underlayment wsu over the existing shingles at the eave end as would be done for a roof laid on bare sheathing.

March 11 2020 by safe harbor roofing. Reroofing is the practice that involves installing a new roof over an existing one. 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. Should old shingles be removed before new installation.

Pros and cons for metal roofing installation. This provides added protection against ice dams.