NDTScan carries out RAAC surveys in Sawston for schools, hospitals, councils, housing providers, universities and commercial owners. Reinforced autoclaved aerated concrete was used in roofs, floors and walls from the late 1950s to the mid 1990s, and a great deal of it is still in service across Cambridgeshire. NDTScan is the UK's specialist in identifying it, assessing it and telling an owner plainly what to do next.
The Department of Health and Social Care's list of hospital sites with confirmed RAAC includes Hinchingbrooke Hospital and North Cambridgeshire Hospital - Wisbech in Cambridgeshire. 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 Cambridgeshire, not as NDTScan projects. Around Sawston 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 Sawston 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 Sawston owner receives a plank-level record, not a general opinion.
One rule applies to every RAAC survey in Sawston. 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 Sawston client.
Scan before you repair. That is the standing advice for every Sawston client, and the reason NDTScan reports what the concrete contains before anyone specifies what to do about it.
Services Available in Sawston
- RAAC Identification Survey GPR based, plank by plank identification of reinforced autoclaved aerated concrete in roofs, floors and walls across Sawston. 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 Cambridgeshire 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 Sawston owner needs an independent second opinion on a survey or a remediation proposal.
RAAC in and around Sawston
Around Sawston 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 Cambridgeshire 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 Peterborough, Cambridge, St Neots, Wisbech, Huntingdon and March and the rest of Cambridgeshire. 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 Sawston 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.