The gravel deposited on the first coat of asphalt preserves the underlying sheets from natural elements, including UV rays and hail damage or heavy wind and rains. The asphalt makes the roof a waterproof system, but using the gravel layer extends the roof lifespan.
To choose what type of gravel and the weight will be required for your project you need to consider the underlying coats, the composition of the building, and the climate. Using Tar and Gravel Layers on Flat Roofs is extremely important since the water and moisture can build up instead of draining off like on a Sloped Roofing System.
The benefits of Tar and Gravel Roof:
- Increases the roof lifespan, lasting about 20 to 25 years;
- Has waterproofing aspects especially for Flat Roofs;
- Helps to decrease the weight of the roof system being suited for Single Ply Roofs;
- Prevents degeneration like cracking or blistering that leads to leaks;
- Protects against the UV rays;
- Prevent weather damage.