Deep retrofit to a detached 1960s house

A detached 1960s house, which has had a (very nearly finished) deep retrofit. As part of a complete refurbishment, a range of energy efficiency improvements have been made to the fabric of the house. Low carbon heating and ventilation systems have also been installed. Information will be provided to visitors about the measures and materials used in the project as well as the process of retrofitting.

Why retrofit?

The UK Climate Change Committee (CCC) report on ‘Progress in reducing emissions’ (June 2023) states that progress on climate action is too slow. Buildings remain the UK’s second highest-emitting sector, accounting for 17% of total direct emissions. The report recommends an urgent co-ordinated shift in how the UK’s 28 million homes and two million non-residential buildings use energy.

Insulation, insulation, insulation

A range of different insulation measures have been used in the house. External wall insulation (EWI) made of glass fibre has been fitted to the back of the house. Internal wall insulation (IWI) made of wood fibre has been fitted in the front rooms of the house. Other insulation measures include recycled plastic loft insulation, beaded cavity wall insulation, and extruded polystyrene insulation under the ground floor. Triple glazed windows add to the overall insulation of the building.

Airtightness & ventilation

The airtightness of the building has been improved with the use of airtightness tape and fabric, paying particular attention to joins and around the windows. A mechanical ventilation system with heat recovery (MVHR) has been installed to ensure that fresh air is circulated around the house. Heat is recovered and recirculated back into the house in the winter. The heat recovery is by-passed in the summer.

Low carbon heating

An air source heat pump (ASHP) has been installed at the back of the house to provide heating and hot water. New radiators, sized for the cooler temperature of the heating system, have been fitted. The house has now been cut off from the gas mains and runs on electricity alone.

Cooling and other future measures

Insulation has created a warm box in the winter, but potentially a hot box in the summer. Although the insulation acts as a barrier, the internal temperature can rise because of solar gain through the windows. Further passive cooling measures are planned to reduce solar gain, including a pergola at the back of the house, external blinds, and other passive shading measures such as tree planting. Cooling measures are likely to become an integral part of retrofit planning as global temperatures rise in coming years. Other future measures could include rainwater harvesting and electricity generation.

Other

While you are in the area you could also visit the nearby 'Deep Retrofit to 1960s Terraced House' and check out the Sydenham Arts Artists Trail: https://sydenhamarts.co.uk/artists-trail.