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THERMABAR 397
Synthetic light-diffusing foil underlay
Thermabar 397 is a foil wall and roof underlay used in commercial and
industrial buildings to provide a vapour control layer and where light
diffusion is required. It is designed to give a clean white finish
enhancing natural light reflection when exposed in warehouse
situations. Thermabar 397 is self-supporting and fire retardant.
Product usage
Thermabar is a synthetic self-supporting roof underlay designed for commercial and
industrial applications. Thermabar 397 is Intended to be light diffusing/reflective and
provide enhancement to the interior space.
INSTALLATION
GUIDE
Appraisal No. 1000
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The recommendations contained in Kingspan’s literature are based on good building practice, but are not an exhaustive statement of all relevant information and are subject to any conditions contained in the Warranty.
All product dimensions and performance claims are subject to any variation caused by normal manufacturing process and tolerances. Furthermore, as the successful performance of the relevant system depends on
numerous factors outside the control of Kingspan (for example quality of workmanship and design), Kingspan shall not be liable for the recommendations in that literature and the performance of the Product, including its
suitability for any purpose or ability to satisfy the relevant provisions of the Building Code, regulations and standards. Literature subject to change without notification. Latest documentation can be found online. E&OE.
Issue 4.0, August 2024
0800 806 595
www.thermakraft.co.nz
Thermakraft and Ausmesh products are brought
to you by Kingspan Insulation NZ Limited.
Thermabar 397
Synthetic light-diffusing foil underlay
Application Method
• Thermabar 397 is installed with the white surface
facing into the building interior space. The underlay
must be fixed at maximum 300mm centres to wall
framing members or as specified by the designer
where subjected to wind. In roof applications, the
underlay can be self-supporting up to a maximum of
1200mm. It can also be laid over a roof underlay
support of galvanised steel wire mesh or safety
mesh. Safety mesh must be used in accordance with
the AS/NZS 4389:2015.
• Thermabar 397 must be pulled taut before fixing.
• Thermabar 397 may be installed vertically or
horizontally. Laps must be a minimum of 150mm
wide. Where the designer intends the underlay toact
as a means of secondary weather defence, the
direction of the laps must ensure that any water
collected is shed to the outer face. End laps must be
made over framing and be no less than 150mm wide.
Refer to the NZ Metal Roof and Wall Cladding Code
of Practice (COP) for full details.
• When Thermabar 397 is used as a vapour control
layer, all laps and junctions must be sealed with
Thermakraft White General Purpose Tape.
• If used on its own as a vapour control layer or for
thermal insulation, Thermabar 397 should be installed
with an air gap separating it from roof cladding. Refer
the NZ Metal Roof and Wall Cladding COP.
• Due to the potential for condensation to form on the
underside of Thermabar 397 when used as a roof or
wall underlay, in direct contact with metal cladding,
installation may require the inclusion of an air gap
separating the foil from the external metal cladding,
especially in applications of high moisture or spaces
with limited ventilation.
• In wall application, lay Thermabar 397 from below
bearers to the top plate.
• Fixing types and requirements for steel framed
structure can be found in the NZ Metal Roof and
Wall COP.
• Any areas damaged during installation must be
replaced.
• Thermabar 397 must be installed by a licensed
building practitioner.
Application Tips
• When fixing the product in windy conditions, care
must be taken due to large sail area.
• Unaffected by LOSP or other solvent based treated
timber. However, LOSP or other solvent based
treated timber must have sufficient time for the
solvent chemical to flash off in well a ventilated area.
Recommended minimum 7 days.
Handling and Storage
Thermabar 397 must be handled with care to prevent
damage such as tearing and roll deformation.
The product must be stored under cover well away
from direct moisture, rainfall contact and sunlight (UV).
Care should be taken not stack other materials on top of
the product.
Appraisal No. 1000