Retrofit the future

'The Nook', Brighton

BBM are now working on the build phase of their demonstration eco-retrofit of a large Brighton house in multiple occupation as part of the Retrofit for the Future programme run by Technology Strategy Board. The challenge from the TSB is to reduce the building’s energy footprint to 17kg of CO2 per annum, a figure which should match the performance requirement which all our housing stock might need to attain such that we can meet the UK’s legally binding 80% carbon reduction targets by 2050.

What is particularly exciting about the retrofit programme is that this project and many others up and down the county are to be monitored for two years such that a database of real world performance can be compared not only against design calculations but also one project against dozens of others. This will aid designers, builders, manufacturers, regulators and client organizations in assessing the cost benefit of various solutions and the challenges to be overcome when forming the strategy for rolling out the much wider society-wide retrofits.

The subject of the project is Brighton based building run by Two Piers Housing Co-operative. It is a large solid brick walled house in a conservation area. In order to comply with restrictions imposed by the  Council on maintaining the appearance of the property, we have adopted a strategy to insulate the front elevation from the inside, whilst the other three elevations, which have relatively little architectural detail, are being insulated on the outside. The ground floor insulation solution was to raise the new finished floor level to that of the main staircase’s first step. A new air tightness membrane, high performance sash windows and casements, solar water heating panels plus a mechanical ventilation and heat recovery system complete the main retrofit features being employed.

Recognising the drivers that housing managers face when posed with a retrofit strategy such as tackling fuel poverty, providing affordable warmth, reducing maintenance requirements, shortening the length of void periods and maintaining asset value, our approach utilizses technologies which are simple and reliable and which will require minimal attention in terms of control by the occupier or maintenance by the landlord; if the technologies and strategies can exist in the background, not impinging upon the residents’ current lifestyles, then such measures, we feel, are likely to be more successful than other approaches which rely on expensive or high maintenance technologies.

In terms of learning outcomes, we hope to:

• map occupant behavior in using the building’s energy systems;

• monitor indoor thermal comfort through the year;

• monitor indoor air quality particularly through the year;

• monitor overall heating costs;

• monitor overall electrical demands;

• monitor overall water demands;

• evaluate embodied energy impacts of materials as well as carbon impact assessment of energy systems.

 

We are employing previously learned lessons from retrofitting & refurbishing existing domestic dwellings and an understanding of the levels of improvement that are practical with well considered specification and detailing, focusing primarily on insulation, avoidance of cold bridging and air tightness and informed by Passivhaus detailing to achieve a holistic passive solution.

We would hope that an outcome of our project would be to provide social landlords with a road map for reducing their housing stock’s carbon load incrementally by identifying the carbon gains from each of the main sections of the proposals.