Roofing Over Existing Flat Roof

One of the keys to over roofing is to tie the air control layer of the roof assembly to the air control layer of the wall assembly.

Roofing over existing flat roof.

The fully adhered membrane wrapped down over the cut back roof deck to tie into the wall water control layer and air control layer photograph 11. Coatings are great flat roof replacement options because they can be directly applied to the roofing surface. Mcelroy metal s retrofit roofing systems consist of adding sub structural components to the existing flat roof to build a slope into the structure and provide a platform to install new metal roofing panels. Once complete your new metal roof will add tremendous curb appeal become more energy efficient and have a decades long service life.

Built up roofing bur was the most common type of flat roof before modified bitumen and membrane roofing were developed. Bur consists of many layers. On the gable ends this was pretty easy. A properly installed layover roof can look and function as well.

On the other hand a full replacement not only leaves you with a better looking higher quality roof it also protects the value of your home and could save you money in the long run. If your current roof is in good condition or you re really short on time it might be your best option. It is an acceptable practice to install a new roof over an existing roof membrane system provided that the roof deck is structurally sound and has been properly prepared to support the added load. Roofing over an existing roof isn t necessarily the wrong choice.

A bottom layer or two of insulation board multiple intermediate layers of tar or asphalt alternated with layers of roofing felt and a top layer of gravel. Installing a new roof over an existing one also called a layover or nailover is often possible although not always the best option. It is the process where roofers install a new roof over your existing one i e. Roofing over an existing roof is also called reroofing or an overlay.

These coatings are liquid applied directly onto the roof surface and then cure once in place. The use of metal retrofit roofs allows the flat roofed buildings to undergo a transformation into a sloped roof building. These new roofs can be either low sloped less than 2 12 functional roofs or high pitched greater than 2 12 architectural roofs depending on the expectations of the building owner.