Built Up Roof

A built up roof is one of the oldest roofing materials and is considered a reliable, if somewhat outdated, roofing option. It is known by multiple names, including a tar and gravel roof and composite roofing. Explore the basics of these roofs, a breakdown of costs involved and the advantages to this roof selection.

“A built up roof consists of multiple layers of felt that are laminted using bitumen. A top level of asphalt, gravel or slag is then applied to this hot layer where some of this top level adheres to the tar and some of left to simply sit on the surface.”

Basics Of A Built Up Roof

A built up roof consists of multiple layers of felt that are laminted using bitumen. A top level of asphalt, gravel or slag is then applied to this hot layer where some of this top level adheres to the tar and some of left to simply sit on the surface. These types of roofs are almost only used on slightly sloped or flat roofs and can last anywhere from 15 – 25 years. Some of the factors thataffect longevity include location, weather conditions, grade of materials, slope or pitch and the surface material. A big factor is whether homeowners opt for a 3-ply, 4-ply or 5-ply with the 5-ply being the most expensive and also the best option for lengevity.


Built Up Roof Cost

Entry / Mid Grade: $2.75 to $4.25 psf
Homeowners can expect the lower to mid grade options to run $275 – $425 per square installed.

Mid / High End: $4.25 to $5.75 psf
Homeowners can expect the lower to mid grade options to run $425 to $575 per square installed.

Learn more on tar and gravel roof cost.

Advantages Of A Built Up Roof

Low Cost
As far as roofs go, built up roofing is a relatively low cost option. The cost and ease of repair is also relatively low and the roofs aren’t super demanding from a maintenance perspective.

Solid Protection
The multiple layers provide good protection for a roof as long as seams do not crack or split. They are well insulated systems that provide a solid thermal performance for a home.

Durable & Reliable
While not the most reliable roof, the number of layers helps to lower the chance of leaks. The roofs can withstand significant foot traffic and they are resistant to most weather conditions.

Downsides

Older Roofs Can Leak
This roofing material can crack or split over time with continued exposure to sun and powerful UV rays. They are especially vulnerable at seams, flashing, chimneys are other areas where the application of the tar and/or gravel is difficult.