Net zero factories: The future of Scottish house building

One of the biggest challenges facing the Scottish house building industry is how to meet the needs of a growing population sustainably. It is estimated that we’ll need to build 100,000 new homes in Scotland over the next decade to meet current housing requirements, but with the construction sector accounting for 47% of the UK’s carbon emissions, we need a solution.

If the sector is serious about playing its part, it must accelerate the adoption of new sustainable ways of working and develop new building methods. Whilst other industries are evolving at pace, and adopting new, novel technologies in the race to net zero, the construction industry is moving slowly.

However, one solution is to drive the development of more novel approaches to sustainable timber based modular housing which allows for greater efficiency in the use of materials.

It is this vision which led NorFrame to begin building a new net zero Timber Engineering factory in Foveran, Aberdeenshire. The new site is situated adjacent to an anaerobic digestion facility, allowing for the factory to be powered by 100% renewable energy through an innovative heat capture system.

From waste to power

Anaerobic digestion (AD) is a process in which bacteria breaks down organic matter, like plant and food waste. During the AD process, plant silage is fermented for six months before being fed into the plant. This process creates heat which is then captured, and redirected to heat the entire factory and office space. Biogas is also produced which is collected to power the manufacturing processes.

Additionally, any waste from the digestion process is then repurposed and used as a fertiliser for next year’s crop. It is a fully organic, closed fuel cycle and has to potential to make a significant contribution to Scotland’s net zero ambitions.

The new £4m facility will span 31,000 sq ft, will produce 20 timber kits per week, and have the capability to meet demand from Scotland’s private and public sectors. It will be constructed to maximise energy efficiency, whilst all timber waste will be minimised and a circular economy approach is being used to ensure that any residual waste is utilised or recycled. This includes the collection and utilisation of rainwater.

Work on the site is well underway and is expected to be finished in the Spring of 2023.

Built-in sustainability

The design of the factory will see many of its products achieve PassivHaus standards where required, meaning its modular timber kits will meet rigorous energy efficiency standards. Backed with over 30 years of international evidence, Passivhaus buildings are subject to rigorous testing criteria to ensure they can provide a high level of occupant comfort using very little energy for heating and cooling.

By maximising energy efficiency, developers can reduce the need for space heating in buildings, massively cutting carbon emissions.

Regulation is key

The Scottish Government also has its own part to play and has committed to taking a leading role. In June this year, Holyrood announced new measures aimed at slashing the carbon emissions of all new-build homes by just under a third (32%). The new energy standards also apply to newly built non-domestic buildings and form plans to reduce emissions across Scotland’s building stock by more than two thirds by 2030.

Reducing energy demand, including improved fabric insulation in new homes to reduce heating needs, is a key obstacle which must be overcome if we are to meet this target. House builders are now also required to streamline the connection of low-carbon heating solutions.

However, developers must look beyond the buildings and examine their own manufacturing processes and technologies. By implementing low-carbon and renewable developments such as wind and solar, or other novel technologies like anaerobic digestion, they can make a real, tangible impact on Scotland’s net zero targets.