Retrofitting – the addition of new technology to an old structure – can save businesses in the UK between £3bn to £5bn, according to Carbon Trust, with the use and/or development of LED lighting, smart metering, and thermal-efficient cladding, among others.
North East London’s Waltham Forest College has already reduced energy costs by £127,000 per annum.
The further education college has created a retrofit project that utilises new cladding extensively for what they have termed as “1960s excrescences,” insulation of solid wall, a system that uses heat exchange for the swimming pool, and double glazing to achieve sustainable energy consumption. Their project won the 2013’s Retro Expo Award for Non-Domestic Retrofit Project of the Year.
21st Century Technology for Old Buildings
According to architect Richard Hopkinson, the overseer of a joint project with Platform 5 and the in-house team of Waltham Forest College, the aim is to achieve zero energy from carbon emissions by the year 2016. Instead of knocking down old buildings that have become inefficient, wonky, and leaking with their lighting and cooling systems, they will use 21st century technology.
Starting from scratch, Hopkinson explained, is “expensive” and “often impractical” as an option. Additionally, he said, the project will change the so-called “college culture” towards renewable energy sources which are “as important” as physical upgrading. People take care over how energy is used when run-down buildings are cared for, he said.
The £35m project’s next phase is the utilisation of a gas-fired switch in a combined power and heat system that will apply heat as to the swimming pool, warm it overnight, and extract the energy from it. The project is also developing an engineering centre to encourage and support excellence in renewable energy technology. Another winner of the Retro Expo award was Gumpp & Maier UK.
According to the firm’s managing director, Martin Montgomery, their winning entry was a testament to “precision engineering”: a façade made of an energy system with timber for its base. The thermal-efficient cladding, Montgomery explained, was difficult because it involved the creation of retrofit layers that are air-tight for old buildings that lean and have walls that “are never straight.”
How Cladding Was Done by Gumpp & Maier
The firm built an extremely accurate model of the building in 3D with traditional surveying tools like the theodolite as well as the latest gizmos like miniature helicopter drones built with the advanced laser scanners. The model took months to develop and transferred from computer-aided design (CAD) software to computer-aided manufacturing (CAM) software for pre-fabrication off-site.
This jigsaw puzzle of structural parts is assembled on-site sans the disruption of occupants vacating their building. This alone, Montgomery said, saved time and money and used zero energy, with the firm successfully cladding 400 square metres of a structure in a record six days. A terraced house, Montgomery added, would take an even shorter period, such as around four days, to complete.
Focusing on Factories and Old Buildings
Residents spend around £40 a week for gas bills but with the retrofit, these would decrease to just about £4 weekly. Cladding is basically thermal-efficient materials that are “sandwiched” to create an airtight cover or “shell” all around an existing old building or structure for heat retention. This can significantly reduce consumption of traditional energy by ten times.
The technology, however, is not cheap. For a terraced house to be clad the homeowner would have to dish out £30,000. Cost is Gumpp & Maier’s primary reason as to why they are currently focusing mostly on factories and old buildings. These structures, Montgomery explained, can afford to spend between £1m and £2m for improving their efficiency in achieving sustainable energy.