RAAC Strengthening for Transport & Infrastructure

Stations, depots and infrastructure buildings cannot simply shut while a roof is replaced. Structured Carbon strengthens RAAC in place with bespoke CFRP, phased into possessions and quiet windows, so operational and passenger buildings keep running.

The RAAC challenge in transport and infrastructure

RAAC appears in the roofs of stations, depots, maintenance and operational buildings, and other infrastructure assets built in the same period. These are live, often 24/7 environments where closing a building affects services, passengers and the wider network. Surveying and managing RAAC here means working within possessions, safety rules and operational demands that leave little room for the disruption of a major rebuild.

Why infrastructure operators need an alternative to replacement

Replacing a roof on an operational asset means closing it, with knock-on effects across a network that depends on every part working. The cost, the programme and the operational impact of stripping out and rebuilding are all magnified in a transport setting. An approach that restores structural safety while keeping the asset running, and which fits into possessions and low-traffic windows, is far better suited to the realities of an operational railway or infrastructure estate.

How we strengthen RAAC in infrastructure buildings

We follow our five-stage RAACSafe™ Protocol. Neil Smuts surveys, scans and assesses the RAAC; John Staves designs a bespoke CFRP strengthening scheme to the exact capacity each structure requires; the CFRP is manufactured in the UK and installed in place; and the strengthened structure is monitored. Because nothing is stripped out, the works are phased into possessions, night shifts and quiet periods.

• Assets kept operational, with work phased into possessions and quiet windows.
• Planned around live operations, to running times, possessions and safety rules.
• A fraction of the cost and programme of closing assets to rebuild.
• Decades of added safe service life from a permanent, moisture-immune solution.

See the numbers on our case study, where, across the tenders we cost, strengthening tailored to the exact roof comes in well below 15 per cent of replacement cost, and read more about CFRP strengthening and RAAC remediation.

Frequently asked questions

Can RAAC be strengthened without closing a station or depot?

In most cases, yes. CFRP is applied in place, so work can be phased into possessions, night shifts and low-traffic windows, keeping passenger areas, depots and operational buildings running rather than closing them.

Can you work around live, 24/7 operations?

Yes. The low-intervention, in-place method is planned with the operator around running times, possessions and safety rules, so the works fit the operational railway or infrastructure environment rather than the other way around.

Is strengthening cheaper than replacing infrastructure buildings?

Typically by a wide margin, and without the operational impact of closing assets to rebuild. Across the tenders we cost, a bespoke scheme tailored to that exact roof frequently comes in well below 15 per cent of the cost of replacement; on one tender a roof costed at around £40 million to replace was priced for strengthening at under £4 million, with no decant.

Who is responsible for the engineering sign-off?

Every scheme is designed and certified by John Staves (CEng FIStructE), a chartered structural engineer and recognised RAAC specialist, working from survey and monitoring led by Neil Smuts, President of the UK Concrete Scanning Standard.