Roof insulation thickness for building regulations will vary depending on the type of insulation used.  Used within a Bauder waterproofing system our products meet current UK Building Regulations Part B for fire protection.

Different insulants have different efficiencies and performance levels which affects the thickness required to meet building regulations.  This table shows a comparison of the insulations when looking to achieve different U-Values on a plywood deck.

  0.16W/M³K on a plywood deck 0.18W/M³K on a plywood deck
Insulation Type Thickness
(mm)
Approx Weight Loading
(Kg/m²)
Thickness
(mm)
Approx Weight Loading
(Kg/m²)
BauderPIR FA-TE 140 4.2 120 3.6
BauderPIR Flatboard 160 4.8 140 4.2
BauderPIR Tapered 150 4.6 130 3.9
Expanded Polystyrene 210 4.9 180 4.2
BauderROCK 230 33.1 200 27.2
BauderXPS CO2 (with Umax) 230 8.1 200 7.0
BauderJFRI 200 (with JFRI VPM) 225 6.75 200 6.0
Cork 240 24.0 210 21
Cellular Glass 240 30.0 210 26.3