Percy Gee

Maple Sunscreening

Vertical 400mm feature fins installed vertically to the mullion.

Percy Gee

About the project

Case Study – Percy Gee Building, University of Leicester – April 2021

Vertical Installation of Large Feature Fin to Mullion

The Percy Gee Building is a striking structure in the heart of the University of Leicester campus. The mixed-use building is the home of the Student Union and a large food court, as well as a dedicated informatics lab, a high-tech media centre and a performance studio.

A recent four storey extension was designed to be visually striking, with aluminium feature fins running vertically around the building. Maple Sunscreening Ltd contacted Blue Sky to find a solution which allowed the installation of the fins without using a secondary supporting structure, as this would run horizontally and detract from the visual impact of the vertical fins.

Challenges and Objectives

The 400mm projection aluminium feature fins needed to be attached to a curtain wall mullion vertically. This is a large projection with the fin weighing as much as 85kg, more importantly it is subject to far higher lateral wind loads.

Many more support brackets would be needed to fit the fins than would have been necessary with a secondary support system (with the fixing centres as low as 600mm), increasing the number of penetrations into the curtain wall mullion significantly. This meant a thermally broken curtain wall bracket had to be used in order to meet the U value requirements (the rate of thermal transmittance) of the building and to ensure there was no interstitial condensation risk.


We introduced Maple Sunscreening Ltd to our innovative i-SOL8 adaptor. This new product is a thermally broken curtain wall bracket which is much stronger than current alternatives, meaning that fewer penetrations are needed for the same, secure, result. This bracket also eliminated the risk of interstitial condensation.

Maple Sunscreening Ltd worked closely with our designers on the design of the brackets and carried out their own in-house testing to ensure they could withstand the high lateral loading necessary. When testing the brackets to the point of destruction, they were actually unable to force the brackets to that point at loads of 10kN, proving them to be stronger than any alternatives on the market – stronger in fact than many in their primary strength axis!

The i-SOL8 brackets resulted in a cost saving due to the significantly lower quantity of brackets, the production assembly and reduced installation time on site. The fixing centres required using the i-SOL8 adaptors were 2m due to Maple Sunscreening Ltd incorporating the adaptors into their client’s build in the early design stage.

The i-SOL8 adaptor provided a fully thermally broken solution with a Chi value of only 0.04W/K per bracket, again a significantly more efficient result than any available curtain wall bracket on the current market.

To discuss how the i-SOL8 adaptor could save time and money, and provide a safe and aesthetically pleasing finish to your building, contact our i-SOL8 team on (+44) 07584 038651 or email

Enquire today
Get in touch