Barons Down Road

Project type: Residential Eco-Retrofit
Project location: Lewes, East Sussex

The refurbishment of Barons Down Road, an 88m2 three-bedroom 1960’s-built terraced house in Lewes, is remarkable for having been independently verified as having a carbon footprint in use of around 0.4 tonnes of carbon per year (largely offset by the roof mounted solar photovoltaic panels) – that is about 90% lower than the national average. The project was awarded an ‘A’ rating energy performance certificate and was optimised to take advantage of five per cent VAT on energy efficiency measures undertaken. The headline achievement of this eco-retrofit is that for around £58K + VAT (circa 2011) the house has been made virtually carbon neutral.

This project beats the government’s built environment target carbon emission rate for the year 2030 (17kg of CO2 per m2) by achieving 4.5kg of CO2 per m2, and it achieved this with a very cost-effective range of carefully considered retrofitted technologies.

The project demonstrated how important the actual choice of candidate building is to carry out an eco-retrofit. The house is part of the Barons Down Road Estate in Lewes which was a privately developed, award winning housing scheme by architects Phippen Randall Parkes from the late 1960’s using a pre-fabricated timber frame system of construction. As a timber framed house, the construction was cost effective to thermally upgrade and being of a well-designed compact terrace typology with plenty of south facing glazing, the original properties were already relatively cheap to heat with excellent levels of daylighting and solar gain.

The project was awarded an AJ Retrofit Award in 2013.

Design strategies included:

(1) Existing flat roof joists infilled with high performance PUR foam to achieve a u-value of 0.14W/m2K;
(1) 3KW photovoltaic solar electric array fitted onto the roof;
(2) External timber framed walls extended inwards and insulated with sheep’s wool quilt to achieve a u-value of 0.18W/m2K;
(3) Acoustic quilt added to the intermediate floor;
(4) Insulative 8mm thick cork floor finish;
(5) Perimeter insulation cut into the existing concrete floor slab;
(6) Retention of recently installed double glazed windows and PVC cladding panels;
(1) & (2) High performance vapour control and air tightness membrane installed to all external walls and underside of the roof.

Deeper Green is passionate about finding cost-effective solutions towards affordable warmth for the Twenty-First Century and Barons Down Road is an ideal example of how to achieve near zero-carbon living with the existing building stock for not a lot of money.