Farnborough Wind Tunnels, Hampshire
More from: How to repair concrete
These two Grade I-listed wind tunnels, once used for testing aircraft, sit in a brownfield site in Farnborough, Hampshire, which is currently being developed by Julian Harrap Architects. In addition to the usual problems, the tunnels suffered from a lack of movement joints. Another issue was the difference between the structures, with one building constructed from fine-grained concrete and the other from aggregate.
All patch repairs were square-cut and filled with a proprietary repair mortar (supplied by Sika). Next, cosmetic layers were added. The aggregate building has a top-coat of render. This render was scored to mimic the original board-marking and daywork joints. The repair mortar matched the fine concrete’s texture reasonably well, so a quartz-textured firring coat was applied to emulate the original bag-rubbed finish. Both buildings were painted to restrict carbon-dioxide penetration.