The Home-Grown Homes Project is gathering speed as it enters its final year. Our Interim Report highlights progress and summarises what we’ve learned so far.

From Little Acorns – Flexi Home for sustainable living

The latest scheme to engage in the project is being developed and built in Wrexham by our members First Choice Housing Association (FCHA) and Williams Homes. The Acorns Flexi Home is part of Welsh Government’s Innovative Housing Programme and will provide lifetime accommodation for one resident. The accessible home is factory manufactured and erected on site linking to an existing FCHA 3-bed bungalow.

The roof and wall panels of the Acorn Flexi Home will be timber framed with wood fibre insulation and timber cladding. Super insulated with high levels of air tightness, mechanical ventilation and heat recovery system, and triple glazed windows, the project also features smart technology to enable the resident to use a number of home appliances and features by voice control.

The project is being designed by Ainsley Gommon Architects and the Innovate Trust is working with FCHA to bring the smart technology to the project. We will assess building performance through a thermal bridge analysis. Working with Cardiff Metropolitan University, Peter Warm of Low Energy Building Practice will conduct a series of calculations to design out potential thermal bridges at building junctions, before Williams Homes start manufacturing. We’ll report on the outcome in the next update.

Testing, Testing, Testing!

Diana Waldron, Cardiff Metropolitan University, our lead on Building Performance Assessment  is planning a pilot day in February with our member Wales & West HA at their Chiltern Close project in Llanishen, Cardiff being built by Hale Homes. Thermography and air tightness tests will be carried out by specialists Build Test Solutions and iRed on completed properties before letting – using two innovative techniques, the Heat Transfer Coefficient test and Pulse test.

In November Diana showed the Powys County Council Clyro project design team the Good Homes Alliance overheating tool and an initial analysis of the overheating risks associated with the project.

Embodied Carbon Results

Team member Eilidh Forster has carried out a second embodied carbon analysis which shows that Clwyd Alyn Housing Association’s Llanbedr project near Ruthin achieves a score that outperforms the target set for 2030 by RIBA, the architects’ professional body. We mentioned the analysis in our last newsletter in November and are very pleased with these impressive results. Details here.

Technical Guidance for Social Housing Developers

We have commissioned the Good Homes Alliance to deliver industry guidance on Building Performance Methodologies which will incorporate case studies developed in these tasks. The Good Homes Alliance is a membership body which promotes and encourages the building of quality sustainable homes and communities and aims to transform the whole of mainstream UK house building into a sustainable endeavour.

We have also commissioned Construction LCA (the consultancy of Jane Anderson – an expert in embodied carbon and author of the BRE Green Guide to Specification) to develop and deliver industry guidance on Embodied Carbon Assessment which will incorporate case studies developed in the Project.

An increasing appetite for Timber Frame

Our latest round of interviews with housing associations and contractors shows some interesting results. Together with project partners BM TRADA we gathered views on timber frame as a choice of construction method and the potential for standardising an approach in Wales. Four contractors and nine housing associations took part in this research. The final report will be available soon. We’re discussing the best way of taking forward the positive results with clients, contractors and timber frame manufacturers – the emerging recommendations identify:

  • Work on performance specifications favouring timber frame
  • Education and training about the benefits of timber and its specification
  • Engagement to improve efficiency in timber frame manufacture
  • Encouragement to partner to achieve a common goal and seek efficiencies
  • Exploration of more factory production and standardisation to solve site labour, cost and quality issues
  • Raising the overall performance of timber frame buildings through improved standard detailing

Models for high-performance buildings

In collaboration with architect Rob Thomas and a design team we are developing a fabric first building solution. A range of fabric designs and models have been prepared to identify potential design requirements for the build solution and suggest a standard low carbon two bed four person house type for feedback and initial performance analysis. This adopts the Welsh Government’s Design Quality Requirements as its basic specification. The design study has considered the Welsh vernacular – potential form, massing and materiality.

Some Passivhaus analysis has been conducted and more is planned. Proposals have been assessed for structural requirements and an initial structural fabric proposal has been developed for discussion. The role of ‘home grown timber’ in the build solution is being considered alongside ‘off the shelf’ standard products and the potential to develop alternative Welsh timber-based products for structural purposes. Concepts have been explored using three-dimensional modelling allowing potential for the project development to follow the BIM protocol.

Encouraging Future Timber Talent

To complement the development of our low carbon build solution we are developing an education project. We are currently exploring ways to embed learning within different sectors of the supply chain and to create learning materials that can be used within universities, colleges and schools. First talks for architecture students have been agreed with Cardiff university.

Carbon Training

An all-day workshop on ‘Operational and Embodied Carbon and How to Reduce It’ with 30 senior executives at Wales & West Housing took place in December delivered in collaboration with the Good Homes Alliance and the Passivhaus Trust.This has already sparked interest with further housing associations. If you are interested in hosting a carbon training day, please get in touch.

Standard window design for social housing a step closer

A group of 16 joinery manufacturers, housing associations and suppliers attended the timber windows workshop on 10 December in Welshpool. Focussing on potential impact and pathways to develop supply chain solutions for Welsh timber windows participants worked on a selection of ideas, based on results from previous workshops. Strong support was given to options around standardised window designs for new buildings and retrofit. Results from the workshop are still being analysed to inform further steps to advance the most promising solutions in 2020.

Increasing Impact in Forestry

As of 2020 board representation of the forestry sector has been strengthened by the appointment of Dominic Driver, Head of Land Stewardship at Natural Resources Wales and Jon Travis, Head of Forestry Reform in Welsh Government. Their input informs our research output and will help to increase potential impact of the project.