The full case study for Avante homes is now available to download.
More information about the Avante Homes project can be found here.
Julia Plaskett, Group Sustainability Executive, Crest Nicholson Plc
Building type, sector and stage
Domestic new build, post completion and early occupancy, South East, Maidstone.
EcoHomes, MVHR, roof lantern, home user guidance, handover process, SIPS
Avante is a housing development by Crest Nicholson PLC. Completed in 2011, it comprises of 150 dwellings in a village setting in Coxheath near Maidstone. There is a mixture of private, affordable and shared ownership housing in the form of detached and terraced houses, flats and apartments. The development meets EcoHomes ‘Excellent' standard.
The homes are constructed using a Structurally Insulated Panel (SIP) system for walls and roof and an innovative roof lantern to maximise daylight and control solar gain (the lantern has integral external shading). Heating is supplied via gas central heating which is connected to radiators in dwellings, with the addition of Mechanical Ventilation with Heat Recovery.
The BPE carried out at Avante by Crest Nicholson and Oxford Brookes University included a study of the building fabric performance of a detached house which included:
- A Co-heating test to determine the heat loss parameter of the dwelling.
Air tightness testing to calculate the infiltration rate and determine leakage paths.
- Heat flux measurements to determine the U-value of different parts of the external fabric.
- Infra-red thermography to visualise thermal bridges.
- Party wall bypass test
The study also included an assessment of design and construction information, installation and commissioning, handover, home user guidance, usability of controls and occupant satisfaction.
Summary of key findings
Positive findings include:
- A better than assumed SAP value for heat loss and thermal bridging elements.
- A slightly better heat loss for the external fabric of a tested home than predicted by SAP.
- Occupant satisfaction with the housing in relation to customer care, location, the contemporary style, high ceilings, open plan layout and levels of natural daylight.
- Occupant satisfaction with overall comfort conditions.
Challenges and opportunities for improvement:
- Lack of design development, and understanding of environmental, construction and user consequences in relation to key innovative features: lantern, large windows, external fabric, and MVHR.
- Air leakage at floor and wall junctions
- Communication issues in relation to the proposed design, installation and commissioning of heating and ventilation systems.
- Occupant dissatisfaction with storage, some internal specifications and some specific comfort conditions.
- Poor occupant and staff understanding of MVHR and heating systems which are potentially linked to the quality of the handover procedure.
Key Performance Indicators
Air tightness: 5.82 m3/hr/m2 @ 50Pa average
Heat loss coefficient: 121.6 W/K
SAP rating: 83 (B-C)