Why do people put stones on the roof?

Pebbles or small rocks spread several inches thick over the outer roof membrane will protect the roof membrane from cracking and peeling due to prolonged sun exposure, thereby extending the life of the roof by several years.

Why do Germans put rocks on their roofs?

During those frigid Alpine winters, the more snow you had on your roof, the better your home was insulated. Ice would freeze the rocks to the roof. The rocks would bear up the logs, and there you have it!

What are rocks on the roof called?

Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional metamorphism.

Why is gravel put on flat roofs?

Gravel flat roofs and pea shingle flat roofs

As ballast, the gravel will help anchor the material underneath and lower the risk of it being blown off in high winds. As protection, the stones absorb some of the sun’s rays, preventing the roof material from becoming brittle over time.

IT IS INTERESTING:  Frequent question: How do shingles protect roof?

What is roof ballast?

A ballasted roof means that the roof membrane is not anchored or adhered in any way to the decking material. It is, however, ballasted, generally with gravel. … The stones used in ballasted roofing are generally 1.5 – 2.5 inches in diameter and applied in a thicker layer.

Can roofs be flat?

Homeowners can choose among three kinds of flat roofs, says Bruce O’Neal, vice president of Matthews Roofing, which has been keeping Chicago’s many flat roofs dry since 1934. What are the different types of flat roofs? Built-up roof (BUR), modified bitumen roof (MBR), and rubber membrane roof (EPDM).

What is the best material for a flat roof?

For many projects, PVC roofing is our preferred choice as the best flat roof material on the market. PVC roofing is somewhat more expensive than other single-ply commercial roofing materials, however it offers a wide range of benefits for the price.

Are gravel roofs good?

Gravel coating reflects sunrays and provides protection from harmful ultraviolet rays. The material does not absorb sunlight which helps you keep your home cool during hot summers. A tar and gravel roof is less prone to wear and tear and doesn’t get damaged easily.

How do you maintain a flat roof?

Tips for Maintaining a Flat Roof

  1. Have it checked periodically. Many home and business owners neglect to inspect their roofs as often as they should. …
  2. Keep it clean. …
  3. Trim back nearby trees. …
  4. Deal with leaks promptly. …
  5. Watch the weight. …
  6. Make sure you have a good drainage system in place.
IT IS INTERESTING:  How do you protect a rubber roof?


How do you extend the life of a flat roof?

Routine Roof Maintenance

  1. Clean the drains and gutters to prevent damage due to waterlogging.
  2. Remove any debris such as leaves, sticks, and tree branches.
  3. Apply sealants to the damaged portions.
  4. Look for any signs of algae, fungus or moss.
  5. Trim any tree branches that are close to the roof.


Is Moss on a flat roof bad?

A lot of wet moss equals a lot of extra weight. Plus, if moisture gets underneath the roof tiles, it could rot the timbers supporting your roof. … Mould growth – The moisture that moss collects can cause other issues such as mould growth.

What is the purpose of roof ballast?

The ballast is used to keep the roofing system cool and of out of the sun’s harmful rays, thus keeping energy costs down. The gravel top coat is also extremely resilient to heavy foot traffic and high-wind scenarios.

Why do roofs require ballast?

Since nothing secures the waterproofing membrane to the roofing materials underneath, ballast is needed for weight to protect the roof from strong winds. Ballast is different from BUR protective gravel. Ballast stones are usually one to two inches thick and applied more generously than on a built-up roof.

How long does a membrane roof last?

A typical commercial flat roof membrane should last on average 20-25 years before needing to be replaced. On the shorter end it could need replacing in 10 years, and on the longer end, it could last even 50 or more years.

IT IS INTERESTING:  Can you use a roof top tent on the ground?
Roofs and roofing