To support the industry in successfully meeting the new H1 insulation Building Code changes, Comfortech have developed a single- and double-layer solution, using new product range, Pink Superbatts insulation.
The Pink Superbatts insulation range are specifically designed to meet the new 5th edition of H1/AS1 and H1/VM1 and are extra wide, at a new width of 460mm.
When meeting the new H1 insulation changes in residential ceilings, one solution that Comfortech recommend using is a single layer of Pink Superbatts R7.0. During installation, it is recommended that these segments are notched so that they can be fitted over and around the truss chords to ensure that the thermal bridge and heat loss pathway are completely sealed.
The decision to promote notching as the preferred installation methodology has been endorsed by industry experts. This is the best way to ensure the in-situ performance reflects the modelling, and it also relies less on a complicated installation methodology to ensure adequate recovery and sealing.
The alternative solution for ceilings is Comfortech's two-layer solution. The first layer of Comfortech’s two-layer solution uses a high-density Pink Superbatts insulation that is the combined height of the truss chord and the gap to the top of the ceiling batten. This first layer would be 110mm for a 90mm truss chord and an R-value of R2.6 or 160mm for a 140mm truss chord and R3.0.
The second layer of this two-layer solution is the new Pink Superbatts R4.5. This second layer should be installed at right angles to the first, in order to close the thermal bridge. A lower R-value second layer can be selected where another compliance pathway method (the Calculation or Modelling method) has been chosen.
Initially it was expected, with the height of insulation now required and the need to maintain a 25mm air gap under the roof underlay, that all new houses would require a raised heel. However, a raised heel has significant cost and height in relation to boundary implications Comfortech has therefore developed an Edge Compression Calculator to demonstrate how Pink Superbatts insulation, under compression and in conjunction with an insulation guard, will meet the requirements of the new H1, of an R3.3 construction R value over the last 500mm of the roof perimeter, and avoid the need for a raised heel. Subsequently, BRANZ has also launched their calculator, which demonstrates the same; a strong endorsement of another of Comfortech's H1 solutions by a key industry player.
For more information on Comfortech's H1 solutions, watch their videos at H1done.co.nz