The eight storey, 183,000 square foot Chamberlain Square building is a central feature of the Paradise district in Birmingham. This ambitious development, surrounded by the city’s most prestigious civic and cultural buildings is set to become the premier business address in Birmingham.

The specification for the roofed areas asked for high thermal performance – a consistent U-value of 0.15 W/m2K – across terraces, podiums, walkways and plant room. A particular feature of this development is the brown roof areas, intended to introduce an element of biodiversity. The roof construction needed to be able to demonstrate a significant warrantied life-span and reliable performance data.

IKO approved contractor Advanced Roofing worked with the technical team at IKO to develop a detailed specification, based around the IKO Hot Melt Roofing System. Hot Melt is an inverted roof system, so installation begins with the application of the waterproofing layer, allowing for the building to be waterproofed quickly and for work on the interior to start immediately. Reinforcement, insulation and finishing layers follow.

This project features significant areas of brown roofs. Vegetated roofs are an increasingly important method of reducing surface water run-off in wet weather. In this instance, rather than using a monoculture seedum roof, the specifiers opted for a brown roof design, providing substrate and seeding with native floral species, combining water capture with biodiversity.

IKO Permatec Anti-Root is IKO’s answer for this situation, with a root inhibitor included in the formulation of the membrane. The result combines robust waterproofing with the added assurance that the performance of the waterproofing membrane will not be compromised by the growing vegetation.

Maintaining the required U-Value with different thicknesses of insulation (allowing for level access from balconies) meant using both IKO enertherm XPS and IKO enertherm Vacuum Insulation Boards (VIP). IKO enertherm products form part of the BBA certified IKO Hot Melt System.

The main contractors regarded achieving a waterproof roof as an immediate priority and ensured all roof areas were completely clear for the roofing installation. Faced with appalling weather, Advanced Roofing had to make use of pumps and vacuums to clear rainwater from surfaces before applying the waterproofing. However, Hot Melt is a fast system to apply and they completed the project ahead of schedule allowing other contractors to bring their programmes forward.

As an IKO approved contractor, Advanced Roofing has access to the combined expertise of a full technical team at IKO: back-up which is much appreciated. “IKO will always advise on the most appropriate materials overcome specific challenges on site and the onsite assistance available from IKO is always helpful.”

Two Chamberlain Square now has an effective, high-performing and BBA approved roofing system with a 20-year materials, workmanship and design single point guarantee.