By the end of this lesson you will have learned about:
- Sources of detailed information about existing retrofit projects, including:
- Low Energy Buildings database
- EMBED Building Performance Platform
- Passive house+
There are many examples of traditional buildings that have been retrofitted. Retrofitters have also started exploring generic insulation solutions relating to non-conventional forms of construction. (The Retrofit for the Future competition includes a high proportion of non-conventional retrofits.)
Examples of retrofits relating to a variety of traditional and non-conventional types can be found on the AECB Low Energy Building Database (LEBD), the EMBED database and in passive house+ magazine.
2. Low Energy Buildings Database
The LEBD has over 200 low energy buildings projects already documented. Over 100 of these are refurbishments (rather than new build).
LEBD (refurbishment filter on) http://www.lowenergybuildings.org.uk/projectbrowser.php?fbt=Refurbishment
The database is searchable by a range of factors. So you can search for refurbishments of solid wall homes, for example, or other construction types. Or you can look for projects which aimed for particular low energy standards, or which met particular levels of measured fuel use.
The following filters focus on retrofits of non-traditional construction:
- LEBD (refurbishment filter on) and “retrofit for the future” and “other” construction type http://www.lowenergybuildings.org.uk/projectbrowser.php?sort=recent&fph=0&fes=Retrofit%20for%20the%20Future&fct=Other
- LEBD (refurbishment filter on) and “steel frame” construction type http://www.lowenergybuildings.org.uk/projectbrowser.php?sort=recent&fph=0&fes=0&fct=Steel%20frame
- LEBD (refurbishment filter on) and “concrete frame” construction type http://www.lowenergybuildings.org.uk/projectbrowser.php?sort=recent&fph=0&fes=0&fct=Concrete%20frame&fbt=Refurbishment
Some projects include very comprehensive information including energy targets, measured energy use before and after retrofit, photographs, and details of the measures installed. Many have a pdf which you can download.
Follow the link above to the LEBD and try some different filters.
On the LEBD (or EMBED or passive house+) find a refurbished property that is similar in original size, type and construction as your own home or a retrofit project that you are working on.
Find one that is also similar in terms of planned / installed measures, if possible.
(If you work on non-traditional projects as well, you may choose to do one traditional construction comparison, and one non-trad comparison.)
EMBED is the Energy Saving Trust’s building performance platform with details of both traditional and non-traditional construction retrofits: http://www.getembed.com/
Some projects have been highlighted below. Generally, the projects selected are at Passivhaus or EnerPHit standard. This is not because of the energy target, but because the methodology has been shown to deliver good results.
Go to the EMBED database and search by the ZA code to read the full report on each project (links to pdfs are given below for those projects highlighted below).
3.1 Traditional construction
Hanley Passivhaus – ZA114U
A whole house approach to the retrofit was achieved through detailed application of Passivhaus principles to the refurbishment of an 19th century terrace house, which prioritises insulation of the fabric, achieving good air tightness with minimal space heating requirement, and whole house heat recovery ventilation. The aim is to make the house easy to inhabit with a low carbon footprint.
The existing building has been carefully surveyed, and proposed fabric and services have been analysed using the Passive House Planning Package, which allows designers to test assumptions thoroughly, and a free exchange of ideas between architect, service engineer and contractor has allowed proposed design details to be well integrated, and assessed for practicality.
This is a small single Victorian terrace house in Hanley, Stoke on Trent. It receives very little passive solar radiation, and is therefore a cold feeling house. PHPP confirms lack of passive solar gain.
…it is typical of houses across the country of this period.
Refurb and regenerate – ZA390M
The house in this project (TSB085) is a 3 bed two storey ‘L’ shaped Victorian end terrace, with solid walls and a traditional pitched roof. The property was configured as two flats. It was in a poor state of repair, with a very low SAP score, primarily due to a lack of any thermal insulation except a settled, single layer of quilt in the roof. Heating was provided by two open front gas fires in each flat, with DHW provided by electric immersion.
This property was selected to demonstrate the potential for extensive whole house refurbishment for properties undergoing major works, providing the potential for radical improvement. Also, the project was selected to assess the potential for refurbishment using internal insulation measures.
Hounslow Passivhaus Retrofit – ZA522P
The house is a 3-bedroom, semi-detached, single-family dwelling built in the early 1950s. The property is located in Hounslow, close to Heathrow airport, and is not located within a conservation area. It is of solid masonry construction.
Decent Homes vs Passivhaus – ZA152J
The scheme strictly followed the principles of the German PassivHaus system and achieved the first retrofit certification in the UK in February 2011. This project has shown that a deep retrofit in London is possible even in a conservation area where only internal insulation was acceptable to the Planning Authority. The works included 200m² of internal insulation, the installation of MVHR ventilation, the provision of solar thermal panels on the roof and the development from scratch of triple glazed sash Victorian look-alike windows.
Barbrook Passivhaus Retrofit – ZA246T
ZA246T is an exciting demonstration project within Exmoor National Park. The aim of the project was to design a refurbishment solution to reduce carbon dioxide emissions from a social housing property by 80%. The project was kick started by Energy Action Devon who brought the team together, including North Devon Homes who own the two properties.
Tower Hamlets Passivhaus Retrofit – ZA521E
…is a 1950-60s brick terrace house with pebble-dash render on the first and second floors. The property is a 3 bedroom mid terrace single family residence and is of solid brick construction, finished with render above the ground floor. The ground floor is comprised of a solid concrete slab.
Using the Passivhaus Planning Package bere:architects took a Passivhaus approach to the retrofit. The project demonstrates that this approach is capable of achieving a reduction in Specific Heat Demand of 92% on post war building stock.
4. Passive house+
AECB members have free access to back-issues of passive house+ magazine, which contains many retrofit case studies. Online, users have access to additional detail (such as construction details) which are not all included in the printed version of the magazine.
Thorough pre-retrofit surveys and building investigations are crucial.
Retrofitters should not make assumptions about materials, construction arrangements and structural or hazardous material aspects when developing retrofit strategies for buildings of non-traditional construction.
Deeper building investigations may be problematic where there are risks of hazardous materials, and all possible sources of information on the non-conventional system should be drawn on.
This lesson has given you access to details of a wide range of retrofit projects.
Some will have been more successful than others in both energy targets and moisture robustness. Some will have assessed the original condition of the existing building very carefully and made a careful retrofit strategy from there.