This is partially embedded into a topcoat of asphalt in order that it be protected from the sun s uv rays.
Pebble ballast roof.
Despite the positive qualities associated with a ballasted roof system there are some challenges.
Ballast is commonly used with roofs made of tar and gravel roof alternatives including ethylene propylene diene monomer epdm polyvinyl chloride pvc and thermoplastic polyolefin tpo single ply flat roofs.
A homogenous sheet with the addition of a layer of random glass fibres in the middle of its thickness which is designed to virtually eliminate shrinkage and provide the necessary dimensional stability.
The gravel ballast secures the roof waterproofing against wind uplift forces.
But the former uses a very thin layer of crushed stone or pea gravel that is not larger than 1 4th inch in diameter.
Holes mean roof leaks and roof leaks mean call the roofer.
The gravel top coat is also extremely resilient to heavy foot traffic and high wind scenarios.
Bur s and ballast roofing systems brs s are topped with rocks.
The single ply membrane and other roof components including thermal insulation are loose laid.
The ballast is used to keep the roofing system cool and of out of the sun s harmful rays thus keeping energy costs down.
Seagulls causing considerable damage to pebble ballast roofing the royal cornwall hospital has recently had a new health wellbeing centre built with a rooftop that housed decorative pebbles known as ballast or pebble ballast roofing.
Single ply roofing materials aren t self adhered nor are they sealed together in any way.
Ballasted roofs can be living green roofs brown roofs paved stone or indeed a combination.
The buildup is ballasted with a gravel layer of at least 50 mm and 80 kg m 2.
The primary concern for sarnafil is ensuring that the roof design meets all the aesthetic requirements whilst providing waterproofing for the roof.
Simply put a ballasted roof is easy to install and basically guaranteed maintenance work for a roofer.
Roof perimeters and penetrations are flashed in accordance with firestone specifications pdf.
Once completed the epdm membrane is held in place using one of the following materials as ballast with a minimum weight of 50 kg m.
Somebody walking on the roof will undoubtedly step on the ballast and put a hole in the membrane.
Ballasted roof systems are simultaneously a roofer s best friend and arch nemesis.
These were proving to be a hit with the existing resident seagulls.