Any concern not having a cavity/air flow behind the boards? Guess not since they're going into a bay that was never designed for today's standards. Thanks.
No issues mate, all the bays along here had a timber frame with a form or lath and render, we removed the old cement board that had failed, the external is insulated so no warm air hits a cold bridge, plus as an extra an additional frame was built on the inside with a foil insulation acting as a warm vapour barrier.
