Generally, roofs with slants and inclines are favored by most residential and commercial residences. Their natural ability to dispose of rain and snow without having to install substantial amounts of insulation has made them an effective and affordable option.
A built-up roof is an integument made up of alternating layers of tar and asphalt materials. They have been used in the U.S. for almost a century and are usually referred to as tar and gravel roofs, as these are some of the primary materials used in its construction.
Built-up roofing takes coal tar-saturated cotton fabrics and gravel-like materials, like asphalt, to assemble alternating layers of bitumen (tar) and roofing felts or ply sheets directly over the roof decks and insulation. The tar is used to soak into the roofing felt and durably hold all the elements together.
Built-up roofing has been around since the 1840s as a reliable option that was readily available for installing new roofs. All it requires is three essential components: a waterproofing component, a reinforcing component and a surfacing component. Most roofs apply variations of these components to create more durable, waterproof roofs. Some even apply 10 ply sheets to one roof! This helps ensure the roof against potential leaking from entering the home while creating a stable platform for any solar panels or roof gardens installed on the roof.
Built-up roofs are very dependable and work great for many reasons, however, they do have some drawbacks. The maintenance of the roof seems to be the primary concern. Built-up roofs are built flat and as one so when a leak occurs it can be difficult to place the location of it, causing one to have to dismantle the entire roof. 1. In order to avoid major damage, maintenance must take place on the roofing system regularly. Re-asphalting the layers is usually not necessary if the roofing surface is properly cared for. This would include draining the rain that forms on the roof after storms and remodeling the top layer with reflective materials to prevent heat damage.
However, because built-up roofs are flat the task of removing layers are much easier. It also creates flexibility in terms of what you can add to your roofing space, should you so desire. Roofing gardens and solar panels are much more easy to install on flat roofs than traditional sloped rooftops.
Then benefits of this type of roof are great, however, the drawbacks are something to consider. Keep in mind that these roofs require a bit of maintenance and labor, the larger the roof the greater the responsibility for upkeep. If your ultimate goal is to save money, this option would be the most cost-effective.