Hassell Drive: Retrofitting and External Insulation of Wimpey No-fines Houses

Bristol City Council [BCC] developed a program called “Warmer Homes” with the idea of improving energy performance/consumption and level of comfort of late 20th century “No fines” solid walled homes, owned by BCC. This type of houses represent a large portion of the residential buildings in Bristol.

The Wimpey No-fines House was a construction method produced by the George Wimpey company and intended for post-World War II mass-production of social housing in the UK. “No-fines” refers to the concrete with no fine aggregates used. Nowadays, this particular type of houses, which only exists in UK, are part of the British landscape. For the UK, arguably the key challenge for heritage buildings, and homes in particular, is significantly to upgrade their thermal performance in winter without causing overheating in summer, particularly as temperatures rise. Previous research has revealed an additional systematic issue, a gap between design expectations and performance in practice, making too often the savings in energy costs lower than expected.

In this project, the University of the West of England (UWE) will examine the effect of externally insulating this type of properties. A sample of these properties will be monitored in terms of energy consumption and comfort levels before, and after insulation works have been carried out over the space of a single winter and summer which is particularly advantageous for the HBIM project in programme terms.

Varying sensor types have been installed throughout the 4 buildings, capturing data on living room, main bedroom, kitchen and bathroom. This data can be analysed for an indication of energy use (Gas and electricity meter) and thermal comfort within monitored zones. A full list of sensors and locations is given below. Sensors have been collecting data from the installation date of 16/09/16. They were located in Livingroom (Temperature; Relative Humidity; Sound; CO2 & VOC; Lux; PIR); Main Bedroom (Temperature; Relative Humidity; Sound; CO2; Lux; PIR); Kitchen (Temperature; Relative Humidity; PIR); and Bathroom (Temperature; Relative Humidity; PIR).

A weather station was also installed at Newtown to record environmental conditions. A Maplin professional solar powered station is used and uploads data to Weather Underground regularly. Both sensor data and weather data for House 1 to 4 can be accessed via APIs and are linked to the web portal under development.