Kidderminster-based Beakbane has designed and manufactured what is probably the highest weatherproof seal in the country.

The fabricated neoprene-coated nylon seal is fitted to the distinctive mast at the top of the Heron Tower in the City of London. With its in-house design and manufacturing capabilities, Beakbane was able to provide a bespoke product, fully finished and ready to install in just two weeks.

Designed by architects Kohn Pederson Fox for Heron International, Heron Tower is an innovative and environmentally focused 46-storey building incorporating offices, bars and restaurants in the heart of the City of London at 110 Bishopsgate.

The 28m-tall cylindrical mast that crowns the tower rises to 230m above sea level at its highest point and was manufactured in two parts to allow it to flex. The Beakbane seal is designed to protect the joint between the two sections from the weather and move with the joint as it flexes.

Beakbane’s customer was JELT Constructive Building Ltd, which was responsible for providing the weatherproof membrane on the roof, and other weatherproof detailing, on behalf of main contractor Skanska.

The Heron Tower in the City of London

JELT’s managing director Eamonn Smith stated: “We took advice from Beakbane on the best material for the job and they came up with the bespoke design we needed to weatherproof the joint in the mast.”

Beakbane recommended a neoprene-coated nylon material to meet the performance requirements of the application and last in excess of 25 years. This material was cut and fabricated to provide a sleeve that was fitted in place round the mast, joined by a Velcro seam, and held firmly in position using a tensioned strap and twist fasteners that passed through eyelets on the seal.

Mr Smith adds: “The service from Beakbane was great; we really had no problems and they were able to provide the seals in a couple of weeks.”

The Heron Tower project was the first time that Beakbane has provided an exterior seal of this kind to the construction sector, but it does have a long track record of supplying bespoke and standard bellows and flexible connectors for interior applications. Typically these are used on HVAC (Heating Ventilation and Air Conditioning) systems, where flexible connectors are used to compensate for misalignments and eliminate vibration, particularly between the fan and the ducting.