The transformation of a tired university building in east London shows unsustainable older structures can be upgraded to deliver industry-leading energy efficiency – without breaking the bank. We were façade and building services engineer, working with architect Fraser Brown MacKenna, on a major upgrade of Queen Mary University’s GE Fogg Building, providing teaching and specialist biohazard laboratories for 70 staff and 1300 students in its biological and chemical sciences faculty.
High performance at low cost
The seven-storey 1970s structure had not worn the years well. Its leaky façade made the building uneconomic to heat in winter. Extreme solar glare meant staff were erecting makeshift blinds to provide shade. The reinforced concrete frame was corroded. Windows were leaking.
We set out to reduce the university’s operating costs and improve occupant comfort in a practical, sustainable and economical way. By overcladding the existing structure with a striking new skin, we protected the structure from further corrosion, improved thermal and energy performance, included renewable energy generation and reduced maintenance costs.
For a budget of £3.95M, Queen Mary University gained a facility matching the best new build projects for performance at a fraction of the cost.
Leading edge energy efficiency
We examined a range of solutions to reduce heating and cooling demand while maintaining stable internal conditions and came up with a threefold solution involving better insulation on the walls, high performance glazing and solar photovoltaic panels on the south and southeast facing roofs. Thermal performance has been improved by 65% for the walls and by 75% for the windows.
To reduce solar heat gain, we initially considered installing fins to shade the façade but by opting for glazing that reduced solar thermal transmission we were able to do away with fins and reduce the capital costs.
The size of new windows was calculated to provide the right balance between natural lighting, ventilation and heat transmission. Tighter seals on the new cladding and windows cut the volume of air leaking from the building by 35%, improving heat retention during winter. Windows making up a fifth of the total façade area can be opened to provide ventilation and natural cooling.
Combined, these measures cut the energy consumed by building services by 70%.
Generating renewable energy
We seized the opportunity to replace the building’s roof lights and windows with new glazing incorporating monocrystalline photovoltaic cells. The outer pane is a solar panel, while the inner pane is coated with a film that minimises solar thermal gain. By combining the cells into the roof light glazing and façade, we significantly reduced the cost. With the aid of government subsidy for renewable energy, the cost of installing photovoltaic panels was close to that of standard double glazing. In all 120sq m of photovoltaic generating capacity were incorporated.
Working in a live environment
The makeover of the GE Fogg Building had to be carried out during term time, with teaching and research activities still under way. We worked closely with the university and contractor to develop a room-by-room decommissioning, handover, refurbishment and recommissioning programme. The project was undertaken in three phases which allowed Charter to gain experience of the overcladding system before progressing to larger, more complex sections.