RAAC roof surveys, weatherproofing & replacement.

RAAC — reinforced autoclaved aerated concrete — is a lightweight precast concrete used widely in flat roofs (and floors) of public buildings from the 1950s to the 1990s. It's less durable than traditional concrete, and as it ages — especially when it gets wet — it can deteriorate and fail with little visible warning. That's why surveying, keeping it dry, and planning its replacement matter.

Public and commercial buildings constructed roughly between the 1950s and mid-1990s — schools, colleges, hospitals and healthcare buildings, council and housing-association property, offices, and industrial units. If a flat roof was built in that era with precast concrete planks, it's worth a RAAC check.

We inspect the roof on-site and by drone, identify suspected RAAC planks, and record their condition, any water ingress, ponding and damage — with photographs and a clear written report. We focus on the roofing side: the covering, drainage and weatherproofing. Structural grading of the RAAC itself is carried out by a structural engineer, who we work alongside.

A structural engineer carries out the formal structural assessment and risk grading of RAAC — that's their discipline and certification. Our role as roofing contractors is the roof: identifying RAAC, keeping it watertight, interim weatherproofing, and full removal and re-roofing. We work hand-in-hand with your engineer so nothing falls between the two.

Water is the main accelerator of RAAC deterioration — leaks, ponding and a failed roof covering let moisture into the planks and corrode the reinforcement, which is exactly what leads to sudden failures. Renewing the waterproofing and clearing drainage is one of the most important and cost-effective things you can do to a known RAAC roof while replacement is planned.

Yes. Where there's active water ingress or damage we can weatherproof and protect the roof quickly as an interim measure, keeping the building usable and reducing further deterioration while structural assessment, funding or full works are arranged.

Yes. We strip out failed RAAC roofs and replace them with a modern, warranted roof system, and we're experienced at delivering large flat-roof replacements around occupied buildings — phased, kept watertight throughout, with minimal disruption. (See our public-sector flat-roof work at Musselburgh Grammar.)

Edinburgh, the Lothians and across Scotland for commercial and public-sector RAAC roofing — surveys, weatherproofing, interim measures and replacement. Call 0800 234 3243 or request a survey online.