Fitzgerald Construction is currently completing work on an education project at Tuahiwi School in Canterbury, where a traditional wall underlay was specified. However, Ivan and the team at Fitzgerald Construction quickly changed this for an alternative that they believed would provide a faster and easier installation. “As soon as I saw it on the plans, I wanted to change out the underlay,” Ivan said. “You can’t use staples with rigid air barriers, and a traditional underlay needs two people for this type of application. I called our local building merchant, and they recommended RAINARMOR Self-Adhesive — and it was the right call.”

Fast, one-person installation


RAINARMOR Self-Adhesive is a synthetic, absorbent flexible roof and wall underlay designed to bond directly to rigid substrates without mechanical fixings or tapes. The peel-and-stick format allows a single installer to apply the wrap cleanly and quickly.

“RAINARMOR made the install faster than a traditional underlay, and only one person was needed,” says Ivan. “The release film is the best feature — you just line it up, peel it back and unroll it. It couldn’t be easier.”

Wind zone and compliance


RAINARMOR meets the requirements of NZS 3604:2011 and is approved for use in Wind Zones up to and including "Extra High" when installed over a rigid substrate. It is also:

• BRANZ Appraised (Appraisal Number: 1277)

• E2/AS1 compliant
• Designed for use as part of a full wall system

Rigid air barrier compatibility and testing


RAINARMOR Self-Adhesive has been tested with common New Zealand rigid substrates, including:


• Kingspan Kooltherm K12 Framing Board
• James Hardie RAB Board
• ECOPLY EcoBarrier
• GIB Weatherline

RAINARMOR Self-Adhesive is an air barrier and is also suitable for both absorbent wall claddings (e.g. timber, brick, fibre cement), or non-absorbent claddings (e.g. metal, plastic), when cavity fixed. This gives builders flexibility to use RAINARMOR Self-Adhesive across a wide range of wall systems.

Project outcome


“It’s great to see a product that’s easy to use and strong on protection — especially on a school project where quality really matters,” Ivan said. “With the Kingspan Thermakraft name behind it, I knew it would do the job.”

Summary


For builders working with rigid air barrier systems or under tight timelines, RAINARMOR Self-Adhesive by Kingspan Thermakraft offers a practical, proven alternative to traditional roof and wall underlays. It reduces installation time, streamlines compliance, and provides confidence on site.