For a RAAC survey in St Albans, NDTScan brings something no general scanning contractor can: hands-on experience of identifying and analysing reinforced autoclaved aerated concrete across the UK, in schools, hospitals, housing, public buildings and commercial estates. Hertfordshire has its share of the roofs and floors built with these planks between the late 1950s and the mid 1990s, and most have never been properly surveyed.
The Department for Education's list of education settings with confirmed RAAC, published in February 2024, includes 7 settings in Hertfordshire, among them Bushey and Oxhey Infant School, Churchfield Church of England Academy and Links Academy. Those are the buildings that made the published lists, which cover schools, colleges and NHS sites. They are named here as evidence that the construction is present in Hertfordshire, not as NDTScan projects. Around St Albans the same roof and floor planks are in council buildings, housing, leisure centres, retail units and industrial sheds that nobody has counted.
The method NDTScan uses in St Albans is the one it uses everywhere: identify first, then assess. Ground penetrating radar reads the plank's internal structure without cutting into it, distinguishing RAAC from the dense precast, hollowcore and timber it is often mistaken for. Every confirmed plank is then inspected for the defects that matter, cracking, deflection, short bearing, water damage, corrosion and earlier repairs, and classified in line with IStructE guidance. The St Albans owner receives a plank-level record, not a general opinion.
One rule applies to every RAAC survey in St Albans. No remediation, propping, strengthening or replacement should be designed until each plank has been identified and its condition recorded. Some of the most expensive RAAC decisions in the UK were taken on roofs that had never been properly surveyed. The survey is the cheapest part of getting the decision right, and NDTScan will say so to every St Albans client.
Scan before you repair. That is the standing advice for every St Albans client, and the reason NDTScan reports what the concrete contains before anyone specifies what to do about it.
Services Available in St Albans
- RAAC Identification Survey GPR based, plank by plank identification of reinforced autoclaved aerated concrete in roofs, floors and walls across St Albans. Confirms what the element is made of without opening it up, and records plank widths, reinforcement and bearing details as evidence.
- RAAC Condition Assessment Plank level inspection of confirmed RAAC for cracking, deflection, bearing length, water ingress, corrosion and previous repairs, classified in line with IStructE guidance. Reported so a Hertfordshire engineer or estates team can act on it directly.
- RAAC Management and Reinspection Monitoring regimes, reinspection intervals and management plans for RAAC that is being kept in service, plus expert input where a St Albans owner needs an independent second opinion on a survey or a remediation proposal.
RAAC in and around St Albans
Around St Albans the work divides into four kinds. Owners who do not know what their roof is made of and need it identified. Owners who know it is RAAC and need every plank assessed and classified in line with IStructE guidance. Estates teams who need a management plan and a reinspection regime for planks staying in service. And Hertfordshire clients who have a survey or a remediation proposal in front of them and want NDTScan's independent view before committing money. Public bodies, housing providers, insurers and private owners all instruct on the same basis.
NDTScan also provides RAAC surveys in Watford, Hemel Hempstead, Stevenage, Welwyn Garden City, Cheshunt and Hatfield and the rest of Hertfordshire. The rest of the region is covered from the East of England RAAC surveys page, and the service itself is described on the RAAC surveys page.
About NDTScan
NDTScan is a specialist non-destructive testing company based in Oxford and led by Neil Smuts, author of The RAAC Book. It is the UK's specialist in the identification and analysis of reinforced autoclaved aerated concrete, and a Level 4 UKCSS Operator, the first in the UK to achieve that certification. RAAC surveys in St Albans sit alongside the company's concrete scanning and structural condition survey work, and every report is written to a standard suitable for engineering acceptance, insurers and dispute work.