A Study for Improving the Timber Construction Supply Chain in Wales

The summer season may be closing but it’s been a busy time for the project with progress on a number of fronts.

Up dates by David Hedges, Home Grown Homes Project Manager.

Home-Grown Timber

Following the success of the visit to Pontrilas Sawmill (covered in the last update) and as part of our growing knowledge of Wales’ timber output in all its forms, we visited Esgair Timber high above Panperthog, close to the Centre of Alternative Technology in August. It’s one of a number of medium-sized mills which remain in Wales. Recently acquired by the Atherton family, famed for their biking success, the mill and surrounding forest will provide another challenge as the business moves through a period of transition.  Dainis Dauksta, Ceri Loxton and I were able to see the sawmill in action, transforming a large Sitka spruce sawn log from the forest into sawn construction material for a social housing project on Anglesey.

Saw cutting large log

Large Sitka spruce sawlog being processed at Esgair sawmill.

Further visits are planned in autumn to map the medium-sized sawmill sector’s activity.

Better Performing Homes

Cardiff Metropolitan University (CMU) Researcher Diana Waldron has been making progress in liaising with the exemplar projects in Powys. At Clyro the Council are developing a small project where Diana has been involved in design team meetings from the early stages. The project is aiming to progress two types of building typologies under different high construction standards – PassivHaus and Zero Carbon Homes. Diana has been providing advice on renewable technologies and energy efficient heating systems such as ground source heat pumps, Building Integrated Photovoltaics (BIPVs) and Transpired Solar Collectors (TSCs).

Architectural 3D impression of new housing development at Clyro

In anticipation of support for projects with Building Performance Evaluation (BPE) at construction and post-construction CMU’s monitoring equipment has been calibrated. Consisting of a number of high-quality monitoring instruments to measure key data to quantify the actual performance of buildings, mainly related to their energy use and the quality of the building fabric. It includes a fan (used for performing pressure tests to measure air tightness), an Anemometer, Thermometer and Barometer (all used to measure data relevant to monitor comfort levels within buildings). This will be crucial to continue to gather evidence to analyse the performance of a completed building and compare it to its ‘as designed” values. This is key to assessing the ‘Performance Gap’. There is also the thermal camera which will enable thermography tests to be carried out, which help to identify issues related to poor insulation, thermal bridges and heat losses.

Post-Occupancy Evaluation (POE) support has been offered to the other exemplar projects that have been more advanced at the construction stage.

Better Manufacturing

Progress in assessing the potential of timber manufacturing sees a round of interviews with housing associations during the coming weeks with the focus on timber frame. While offsite construction of timber frame buildings offers many benefits for speed, cost and quality, some of these can be diluted by the current conventions of the construction industry. Bespoke plans, choice of untried or untested design details and compromises during the construction phase can mean that each building is effectively a prototype. Working with BM TRADA (the Timber Research & Development Association) we are looking to explore how and why housing associations procure their developments in the way they do, and whether there is an appetite for standard house types, standard design details and standard manufacturing to help deliver better performing buildings. We are particularly interested in procurement methods, risk, social, economic and political factors that can influence what types of buildings are actually delivered.

Better Timber Housing Solutions

In our last update we reported on the team of specialists we have appointed to develop a zero-carbon building solution. The team comprises experts in sustainable architecture, high performance housing construction, structural engineering, M&E, timber construction, zero carbon building and project management. The team are:

Alan Clarke (M&E)

Beth Williams (Structural Engineer)

Diana Waldron (Housing Performance)

David Hedges (Housing)

Gary Newman (CEO Woodknowledge Wales)

James Moxey (Project Lead)

Nick Grant (Passive House Designer)

Rob Thomas (Architect)

The team met over the summer at two project workshops to refine the brief for the project and to start the process of developing concept design solutions. We will work closely with housing associations, manufacturers and construction companies in Wales to test and refine our approach so that it supports the development of zero carbon housing that is affordable.

With local and national governments prioritising effective responses to the climate emergency the time is ideal for this project that aims to present a zero carbon solution for the commissioning and creation of new housing.

We expect this to be the start of a process with incremental refinement of the designs over time and as requirements change. We plan to make the designs available as open source documents, free to all house builders as a direct response to the climate emergency.