Your Flat Roofing quick reference guide


With so many flat roofing options available, how do you match the right product to the right job and budget?

Roofing has come a long way since using the woolly skin of a giant mammoth to keep the rain out. These days, we’re spoilt for choice with the sheer number of solid and secure options available.

Flat roofing, in particular, came into its stride in the early 19th century, with the invention of liquid waterproofing. Originally a combination of natural bitumen and man-made materials – such as jute, straw and rag felt – by the mid-20th century the modern materials we see today were becoming popular. These have been continually developed and enhanced in the intervening years to create the vast array of high quality flat roofing materials we now use.
Variety is good; it means you have the opportunity to use different techniques for different jobs and requirements, and match the right product to the right job and budget. However, to make the right choices, you need to know what your options are.

Here’s a quick overview of the products available and their main uses:

REINFORCED BITUMINOUS MEMBRANES

A variety of bituminous membranes offering varied application advantages:

  • APP is tough and easy to apply in a range of temperatures
  • SBS deals better with weather stresses and temperature fluctuations
  • Pour and roll – requires bitumen heated to over 200°C
  • Torch-on – underside treated with thermofusible bitumen, heated with a propane torch then rolled and applied hot, so no bonding bitumen is required
  • Self-adhesive – needs no heating as backing strips away

LIQUID WATERPROOFING SYSTEMS

Ready to use, single liquid component, with strong adhesion to most conventional substrates:

  • Cost effective wet-on-wet application and water repellent on application
  • Can be applied all year round above 0°C
  • No shrinkage – 100% solids
  • Virtually odourless and extremely low VOCs
  • Minimum wastage – unused product can be stored and reused
  • Can be recoated

GRP (GLASS REINFORCED PLASTICS) ROOFING SYSTEMS

Extremely strong high performance system, forming to any shape:

  • Cold applied – quick and easy to apply by both roller and brush for tack free finish
  • Cures to a hard, very attractive, seamless finish
  • Colour change system shows when catalyst is added to resin
  • Isophthalic topcoat gives superior performance in finish, long-term UV protection and weathering
  • Can be applied to concrete surfaces and metals when using G4 Primer
  • Remains watertight and maintenance free for many years

EPDM (ETHYLENE PROPYLENE DIENE MONOMER)

Easily installed, strong and lightweight membrane:

  • Economical
  • Highly flexible
  • Faster installation reduces labour costs
  • Pressure Sensitive accessories available for virtually any penetration or detail
  • Unmatched weatherability – resistance to ozone, UV radiation and extremes of temperature
  • Little or no maintenance

SINGLE PLY

Advanced stylish membrane:

  • Quick and clean installation, perfect for covering large areas
  • Cold applied
  • Highly flexible and elastic with little or no maintenance
  • Overlays existing roofs saving money and the environment
  • Can be fitted in most weather conditions
  • Finish gives a clean and attractive look

ASPHALT

Traditional material that is smooth, seamless and durable:

  • Proven technology tested over many years
  • Quick and easy to install
  • Flexible so suitable for moulding around irregular shapes
  • Combines with thermal insulation to achieve a required U-value
  • Can be suitable for foot traffic, increase solar reflectivity and give a more decorative finish

PAINTS AND SOLUTIONS

Ideal for maintenance or emergency repairs:

  • Cost-effective, giving exceptional value for money
  • Suitable for wet weather application
  • Unaffected by temperature change
  • Gives outstanding adhesion
  • Ready-to-use for instant waterproof protection
  • Provide maximum solar reflectivity if solar reflective paint is used
  • Forms an incredibly tough, fibre reinforced, seamless, flexible membrane
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