Flat RoofRoofing being an important part of the house, people spent a good amount on roofing. Thus, if you are spending such a good amount you should be aware about what you are choosing and what are the facts, pros and cons of that roofing. Thus if you are opting for a flat roofing these are some of the facts you should be aware of.

  • Single ply, built up and spray on/paint on are the three general types of flat roofing materials.
  • Single ply refers to just one layer of membrane as weather surface and waterproofing. The most common types of single ply roofing membrane are PVC and TPO.
  • Commercial and residential construction uses this single ply roofing membrane as the most popular roofing material.
  • Different types of single ply membranes are different in nature. PVC, TPO and EPDM are different in terms of durability, costing, specs and formulations.
  • 6-18 feet is the range in width of single ply membranes. Widely used membranes are around 10 feet.
  • The average thickness of this membrane should be atleast 50 mil. The common range of single ply roof ranges from 45 to 90 mil.
  • The next type of roof is built up roof which is built up with more and more layers for its longetivity and durability and hence it is named built up. The materials used in its manufacturing process are asphalt, rolled asphalt, modified bitumen, tar saturated paper and liquid tar with gravel.
  • Any type of built up roofing needs a positive roof slope which should be at least ½ inches.
  • Built up roofing are stopped being used in commercial properties as it is now considered to be outdated by modern construction standards. Where as it is still used in residential properties because of its low cost quality.
  • Next type of flat roofing is spray on/paints on roofs. The two most common types of spray on roofs are spray foam insulation which is sprayed directly on the roof deck and then it is coated with acrylic or urethane coating. Along with it a layer of crushed stones is also sprayed. Another spray on type is roof coatings which is manufactured and used to extend the service life by 10 to 15 years.
  • The costing of flat roofing sets at a price which is lower than pitches/sloped roofs.
  • The cheapest single ply membrane is EPDM whose rubber cost of material is about $1.5 per square foot.
  • The cost of TPO roofing is about $1.7 per square foot.
  • The cost of PVC roofing is about $1.9 per square foot.
  • The costing of modified bitumen and rolled asphalt roofs is ranging between $1.3 to 2.2 per square foot which depends upon number of piles.
  • The rarest of all is tar roofs which are to be specially ordered and thus these material prices are not available.
  • Single ply membranes are either fully adhered or mechanically attached.
  • In fully adhered method, installation comprises of gluing the membrane directly to insulation or to the substrate.
  • Method of mechanically attached comprises installation through fastening each row of membrane to the roof with the help of roofing screws and barbed plates.