Vogue garage conversions choose Kingspan insulation products for garage conversions.

TP10 Thermapitch insulation for garage conversion pitched roofs
PREMIUM PERFORMANCE

For this application we recommend the use of either Kingspan Thermapitch TP10 zero ODP (high performance CFC/HCFC–free rigid urethane insulation) or Kingspan Kooltherm® K7 Pitched Roof Board (premium performance CFC/HCFC–free rigid phenolic insulation) with Kingspan Thermawall TW56 zero ODP beneath the rafters.

Product data	Achieving “U” values

The requirement for a vapour control layer and/or under tile ventilation should be assessed to BS 5250: 1989 (1995). Vapour check plasterboard or a separate vapour control layer can be used as preferred.

Kingspan Thermawall TW56 zero ODP contains an integral vapour control layer.

Calculation based on rafters being underlined with Kingspan Thermawall TW56 zero ODP comprising 12.5 mm plasterboard and 25 mm insulation of thermal conductivity 0.022 W/m.K. Thickness shown in the table above is only the between rafter component. Calculations are based on 50 mm wide rafters, assuming 50 mm ventilated airspace between the rafters above the insulation layer installed between them.

The l–value quoted is in accordance with the Harmonised European Standard BS EN 13165 (urethane) and BS EN 13166 (phenolic) using so called 90/90 principles. Comparison with alternative products may not be appropriate unless the same procedures have been followed.

If tiles are to be used then this normally necessitates the use of counter battens and tiling battens over the breathable sarking membrane to allow for water drainage and attachment of the tiles.

Fixing details
Between Rafter Insulation
To maintain a 50 mm ventilated void above the insulation and to ensure the boards are flush with the bottom of the rafters, side nail battens to the rafters in the appropriate position to provide a stop’.
Boards cut individually to fit the rafter spacing and simply install the correct thickness of insulation in such a manner that it is flush with the bottom of the rafters but does not fill the rafter depth.
Measures the space between the rafters before cutting the boards as spacing varies. In all cases insure that insulation boards between rafters are fitted tightly. Fill any gaps with expanding urethane sealant.

Under Rafter Insulation
Fix the Kingspan Thermawall TW56 zero ODP at right angles to the underside of the rafters. Boards should be fixed with galvanised clout nails, long enough to allow 25 mm penetration of the timber. These should be placed at 150 mm centres and not less than 10 mm from the edges of the board along all supporting edges.
All edges of Kingspan Thermawall TW56 zero ODP must be supported. This will necessitate the use of noggins placed between rafters to correspond with the long edges of the boards.

General
Ensure accurate trimming to achieve close butting joints and continuity of insulation.
Ensure the continuity of the insulation at the ridge.
Ventilation should be provided in accordance with Approved Document F, F2 Condensation in Roofs) or the Building Regulations or Technical Standard K Ventilation of Buildings, Regulation 23) of the Building Standards (Scotland).
To prevent a cold bridge, tightly pack flexible insulation material between the rafters and the cavity closer.
Boards should be cut using a sharp knife or fine-toothed saw.

The insulation products described above are the materials of choice of Vogue Garage Conversions and are supplied by - Kingspan Insulation Ltd