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Flat Roofs

While not really flat
or horizontal, a flat roof is usually nearly horizontal and is made
with materials that allow water to run off freely from a very slight
inclination.

Unlike traditional flat
roofs that were made with tar and gravel, modern flat roofs tend to
use a continuous membrane covering which can better resist pools of
standing water. These membranes are applied as a continuous sheet
where possible, though sealants and adhesives are available to allow
for bonding multiple sheets and dealing with structures penetrating
the roof surface. More expensive flat roofs are made with sealed
metal roofs, utilizing copper or tin, which are soldered to interlock
the systems of metal panels of the roof.

While a few of the
famous Modernist architects, like Le Corbusier, viewed flat roofs as
a living area, flat roofs cannot be used that way until the roofing
membrane is properly protected. One way to accomplish this is to
build a deck or use paving stones to protect the roof membrane.

An interesting method
to protect the roofing membrane is a Green Roof, which uses a layer
of topsoil and grasses. However, it is important not to plant
anything that has roots that would penetrate the roof membrane.

The
most common type of flat roof is the asphalt built up roof (BUR),
made of multiple layers of reinforcing plies and asphalt. The
reflectivity of built up roofs depend on the surfacing material used.
Gravel is the most common and they are referred to as tar and gravel
roofs. But the degradation by UV-rays of the asphalt as well as
serious air pollution are problems and other substances are becoming
more popular.

A flat roof must be maintained properly to last a typical 10 year
life expectancy.

Interestingly,
the old fashioned BUR roofs that are properly maintained have lasted
over 100 years. Maintenance includes removal of ponding water with a
siphon that runs regularly. All roofs should be inspected
semi-annually and after major storms.

Perhaps the simplest roof design available, a flat roof is a great choice for those interested in getting the most out of their living space. Worried about water run-off? Fortunately, new strides in building materials have made this concern virtually obsolete. Here is some more information.

Costs

The cost of a flat roof depends on the type and quality of materials, size of your home and the cost of labor. However, the simple design makes them less expensive than other types of roofs. Get in touch with a local roofer for price quotes and more information.

Pros

Flat roofs are simple to build, and therefore cheaper than other roof styles.

The flat surface allows for easy inspection and maintenance.

With the right materials, a flat roof can be used as additional living space.

Cons

Flat roofs may not work with all types of home styles.

The lack of a slope makes flat roofs susceptible to water pooling.

Most flat roofs only have a 10-year life expectancy.

Durability

A flat roof must be maintained properly to last a typical 10-year life expectancy. However, interestingly enough, the old fashioned BUR (built-up) roofs that are properly maintained have lasted over 100 years. See More Information below to learn about built-up roofs.

Maintenance

The maintenance required of a flat roof includes removal of pooling water with a siphon that runs regularly. All roofs should be inspected semi-annually and after major storms.

Common Questions and Answers

Can flat roofs be built to be weatherproof?

Yes, unlike traditional flat roofs that were made with tar and gravel, modern flat roofs tend to use a continuous membrane covering, which can better resist pools of standing water. These membranes are applied as a continuous sheet where possible, though

Can flat roofs be used as another living area?

While a few of the famous Modernist architects like Le Corbusier viewed flat roofs as a living area, flat roofs cannot be used that way until the roofing membrane is properly protected. One way to accomplish this is to

History

One of the oldest roof styles around, the flat roof can be traced as far back as the Minoan period around 2000 B.C.

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