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Why Choose Tapered Roof Insulation (a.k.a. Cut to Falls Insulation)?

 

A Flat roof should never be truly flat! The goal of tapered roof insulation systems is to reduce or eliminate the amount of standing water on the membrane when the roof deck does not provide adequate slope. Ponding water can not only have an adverse effect on the waterproofing membrane but can add unwanted weight to the structural deck and can make routine maintenance more difficult and in some cases more dangerous. A properly designed tapered roof insulation system not only provides the positive drainage needed but also helps extend the life of the roof membrane.

 

The provision of a fall within a warm deck flat roof is normally achieved in one of three ways; tapered insulation, utilising timber firings under a plywood base or by laying a screed to falls.

 

Independent studies have assessed both the cost and speed of each type of installation.

 

Tapered insulation proves to be:

 

  • Less costly to install
  • Quicker to install – Estimated drying out times for screed to falls systems are in the region of 100 days +, with insulation and waterproofing still to be fixed. Estimated installation times for a tapered insulation systems and the waterproofing membrane are between 50 – 150m² per day (dependant upon deck type and fixing method).
  • Reduced Weight – standard sand: cement screed weighs approximately 2000kg/m³. Tapered insulation systems varying dependant upon insulant type; e.g. Rigid PIR – 32kg/m³, Rock Mineral Fibre – up to 180kg/m³. Hence tapered insulation offers a huge benefit in the reduced additional weight added to the structure.
  • More suitable for complex fall configurations - Timber Firings can be complex to install when cross falls are required. There is also the potential for condensation risk within voids formed by the firings.

 

Additionally with tapered insulation the required fall can be achieved and the necessary thermal insulation is provided in ‘one-go’.