Hill Quays, Residential Apartments, Manchester

Project Overview

Hill Quays is a prominent mixed-use development in central Manchester comprising 266 residential apartments, ground-floor commercial units and basement parking, arranged across two interconnected buildings — Block A and Block B — linked by elevated walkways and spanning approximately 3,500 m² of façade area.

Block B, which accommodates 42 high-specification residential units, was identified as the primary focus for a comprehensive façade remediation programme. The project was among the first in the region to secure support from the Building Safety Fund (BSF), established to address life-safety fire risks associated with external wall systems on buildings over 18 metres in height.

Wetherby Wall Systems was appointed to design and supply a fully engineered external wall insulation (EWI) solution that would enhance fire performance, durability and regulatory compliance while maintaining the building’s architectural character and thermal efficiency.

Design and Specification Objectives

The façade specification was developed to:

• Replace the existing system with a like-for-like A2-rated, non-combustible external wall system.
• Improve fire performance and life safety compliance in line with BSF and Building Regulations requirements.
• Maintain or improve thermal efficiency without altering the building line or architectural intent.
• Provide a robust, versatile façade solution capable of accommodating complex geometry and mixed substrates.
• Ensure long-term durability and weather resistance for a high-rise urban environment.

Although the original performance requirement targeted a U-value of 0.28 W/m²K, the completed system exceeded expectations, achieving a final performance of 0.24 W/m²K.

System Specification

The installed Wetherby system comprised the following build-up:

• Substrate:
• Mixed construction including Steel Framing System (SFS) and traditional masonry.
• Sheathing Board:
• WeatherKem Calcium Fibre Cement Board (A1 non-combustible), introduced as a replacement sheathing layer where original system data was unavailable. This provided a compliant, stable and fire-safe backing for the EWI system.
• Insulation:
• ROCKWOOL stone wool insulation, selected for its A2-s1,d0 fire classification in accordance with BS EN 13501-1, along with excellent thermal, acoustic and durability characteristics.
• Insulation Thicknesses:
• Variable thicknesses of 30 mm, 40 mm, 50 mm, 60 mm and 90 mm were specified to accommodate façade articulation, columns and complex interface zones while maintaining consistent thermal performance across elevations.
• Fixing Strategy:
• Direct mechanical fixing into studs and masonry substrates, with pre-installation pull-out testing ensuring minimum fixing performance of ≥1.0 kN. Fixing type and density were tailored to substrate condition and insulation thickness.
• Reinforcement and Base Coat:
• K+A reinforced basecoat, incorporating alkali-resistant mesh for impact resistance and long-term system stability.
• Finish:
• Wetherby 4S Silicone Render (Four Seasons Render), selected for its extended application window (1°C to 30°C and up to 95% relative humidity), providing flexibility in programme delivery and a durable, weather-resistant façade finish.

Thermal Performance

• Pre-refurbishment U-value: 0.28 W/m²K
• Post-refurbishment U-value: 0.24 W/m²K

The system delivered improved thermal performance while meeting enhanced fire and durability requirements for a high-rise residential environment.

Installation and Technical Delivery

The project presented several technical challenges, including:

• Mixed substrates comprising SFS and masonry.
• Slender façade elements, projecting columns and confined interface zones.
• Management of multiple insulation thicknesses across complex elevations.

Key delivery measures included:

• Extensive testing and validation of existing façade elements.
• Development of a revised specification incorporating A1-rated sheathing.
• On-site coordination between Wetherby Wall Systems, Springforward Management Ltd and Cobe Contracting Limited.
• Ongoing technical support and quality assurance to ensure compliance with specification guidance and regulatory standards.

Performance Outcomes

• Enhanced fire performance and life safety compliance through a non-combustible, A2-rated façade system.
• Improved thermal efficiency exceeding initial design targets.
• Durable, weather-resistant façade suitable for high-rise urban exposure.
• Successful remediation delivered under Building Safety Fund requirements.

Architect and Specifier Value

This project demonstrates the application of a direct-fix stone wool EWI system for high-rise remediation and fire safety compliance. It highlights the importance of:

• Early testing and validation of existing façade systems.
• Integration of A1-rated sheathing boards within remediation strategies.
• Variable insulation specification to address complex architectural geometry.
• Collaboration between system provider, installer and main contractor to meet regulatory and funding requirements.

Project Significance

Hill Quays serves as a benchmark for Building Safety Fund–supported façade remediation, illustrating how performance-led specification and system-based design can deliver enhanced fire safety, durability and energy efficiency within complex, mixed-use high-rise developments.