Bituminous waterproofing
Encyclopedia
Bituminous waterproofing systems are designed to protect residential and commercial buildings. Bitumen is a mixed substance made up of organic liquids that are highly sticky and viscous, and are waterproof.
Roofing felt components
Bituminous membranes are made up of more than one product:- Bitumen - Mixed with a filler component such as limestoneLimestoneLimestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....
or sandSandSand is a naturally occurring granular material composed of finely divided rock and mineral particles.The composition of sand is highly variable, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal...
. Polymers are added to the bitumen such as APP (atactic polypropylene) a plastic additive that gives rigidity and tear resistance, or SBS (styrene butadiene styrene) a rubber additive that gives more elastic benefits. - Base Products - PolyesterPolyesterPolyester is a category of polymers which contain the ester functional group in their main chain. Although there are many polyesters, the term "polyester" as a specific material most commonly refers to polyethylene terephthalate...
, fibre glass, rag fibre (hessian), and paper. These products are bought in roll format and are pulled through the bitumen mixes on huge rollers. The base product becomes saturated in huge tanks by the tarTarTar is modified pitch produced primarily from the wood and roots of pine by destructive distillation under pyrolysis. Production and trade in tar was a major contributor in the economies of Northern Europe and Colonial America. Its main use was in preserving wooden vessels against rot. The largest...
like bitumen substance, creating rolls of waterproof material. - Mineral - (Optional) Small granules are added to the top of the felt, decreasing the products fire vulnerability.
- Thin, transparent film - This product is added to the base of the felt during manufacturing on all torch-on products. This stops the felt from sticking to itself when rolled up during the packaging process.
Benefits
Bituminous roofing products are used for waterproofing roofs on buildings.- Benefits include that they move with the structure and do not absorb water. Bitumen is a hydrocarbon and is created from crude oil.
- The products have an extremely long life span, with most membranes having BS (British StandardsBritish StandardsBritish Standards are the standards produced by BSI Group which is incorporated under a Royal Charter...
) marks against each product name. - The fumes given off during installation are not harmful to human health and there is low noise pollution during application.
- Bituminous membranes protect insulation and can reflect harmful sun rays. New products also contain photovoltaic cells that can produce solar energy.
- Bitumen is not water soluble, non-biodegradable, not classified as carcinogenic and does not release harmful toxins.