The world’s first Lighthouse helipad has been repaired and protected using products manufactured by Flexcrete Technologies Limited, the UK’s leading independent manufacturer of engineering quality technical mortars and high performance coatings.
The reinforced concrete foundations of the helipad at Cornwall’s Wolf Rock Lighthouse had deteriorated over time and a remedial solution was required to repair the steel reinforcement and surrounding concrete. Wolf Rock Lighthouse is located some four miles from Land’s End and stands at 41-metres high. It first entered service in 1870 and took nine years to build due to the precarious weather conditions commonly experienced between Cornwall and the Isles of Scilly. The Lighthouse was the first in the world to have a helipad when it was originally fitted in 1972.
A survey of the helipad foundations identified issues with the steel reinforcement and base plate supporting posts; these were corroding and breaking out the surrounding concrete cover. The concrete base was originally constructed with 16 pockets for the base plates to be fixed at a later date, thus creating a vertical weak spot around each base plate.
The refurbishment works were carried out on behalf of the General Lighthouse Authority and the Corporation of Trinity House. Two Flexcrete products – Steel Reinforcement Protector 841 and Monomix – were specified on the basis of their outstanding track record of use in challenging coastal projects all around the world. Due to the height of the Lighthouse and difficulty in gaining access, steeplejacks were employed to access the outer edges of the helipad’s concrete base.
All defective concrete was cut out before the steel reinforcement was grit blasted and two coats of Steel Reinforcement Protector 841 were applied. 841 forms a highly alkaline coating which not only protects the steel from aggressive acid gases, moisture and chlorides, but passivates the steel surface chemically to prevent further rust formation. It also forms an excellent bond with Flexcrete concrete repair mortars and Monomix was subsequently applied.
Monomix is a single component, polymer modified, high build, non-shrinking mortar certified to EN 1504 – the pan European standard for concrete repair. Its dense matrix provides excellent protection against moisture and chlorides and it is waterproof to 10 bar pressure. Its quick hardening properties and ability to be rapidly mixed and applied on-site were all crucial considerations in this project.
Flexcrete Technologies Limited is the UK’s leading independent manufacturer of technical mortars and high performance coatings. With origins dating back to 1983, the company manufactures a wide range of concrete repair mortars, fairing coats, waterproof cementitious coatings and decorative protective coatings. With its head office and manufacturing complex based in Leyland, North West England, Flexcrete products are available from stockholding distributors all around the UK. The company also has a global presence through international agents and distributors in 65 countries worldwide with export sales accounting for over 50% of its business.