How to adopt a fabric first approach in your self-build design
What is a fabric first approach?
Taking a ‘fabric first’ approach is all about choosing the right materials from the start of your self-build project. These fabrics could transform the way your self-build home performs.
When we talk about the ‘fabric’ of a building, this refers to the building envelope that separates the indoor environment with the outdoor. In other words, it’s the physical parts – such as the structure, windows, doors, frames and insulation – that all work together to create the building.
If you use high performing materials and design to achieve airtightness, and minimise issues like thermal bridging, this reduces the energy needed to heat and cool the building.
Creating more energy efficient homes will help to reduce the impact on the environment, while cutting energy bills and potentially making the space more comfortable for the user. There is no need for later considerations like low carbon energy sources.
Future Homes Standard
A fabric first approach features heavily in the Future Homes Standard consultation, which aims to improve the quality of housing in England.
The Future Homes Standard is due to come into effect in 2025 and will ensure that new homes in England produce at least 75% lower CO2 emissions compared to those built to current standards.
Many stakeholders responding to the Future Homes Standard consultation – including designers, engineers, local authorities, builders, and developers – highlighted the importance of taking a fabric first approach when setting the new standard.
In response, the government has stated: “We have settled on a revised package of performance metrics that will ensure a fabric first approach is at the heart of all new homes alongside a low carbon heating system.”
Taking a fabric first approach in your self-build
So, you’re in the home design stage and you’ve decided to create a fabric first self-build but where do you start?
First things first, you need to think about four key factors:
1/ Choose energy efficient materials
Employing high quality insulation – whether loft, floor, or wall – will help to retain heat and reduce heat loss. Other materials like high performing glazing can also help to keep heat in.
Insulation works by stopping heat energy from leaving a building. Really high-level insulation should make it as hard as possible if not impossible for the heat energy to find its way to colder surfaces reducing the risk of it getting lost through the transfer of heat. There are lots of products that you can use to achieve a high standard of insulation - mineral wool or phenolic foam are high quality options with good thermal resistance, as well as sheep’s wool.
Saint-Gobain Insulation UK offers a comprehensive range of thermal insulation solutions, from loft or flat roof insulation, to room in the roof, floor and wall insulation.
2/ Maximise solar gains
Double or triple glazing is required, however you should also think about the position and location of the building and its windows, doors and skylights. Too much glazing in the wrong places can cause overheating and make a home feel like a greenhouse. But with clever design and the latest innovations in glazing, you can avoid overheating while taking advantage of the sun’s natural light and heat.
Saint-Gobain Glass manufactures some of the UK’s most energy efficient glass. Why not check out Planitherm: a range of modern, high-performance glazing for the home made by Saint-Gobain Glass. Planitherm glass doesn't just meet UK energy standards and building regulations, it exceeds them: offering better efficiency than traditional double glazing.
3/ Increase airtightness
Mind that gap!
Gaps in the building envelope can cause heat to escape or drafts, so you want to avoid any unwanted spaces where possible. You should also check the frames on windows and doors. A designed and considered airtightness strategy is a key consideration.
4/ Avoid thermal bridging
Thermal bridging occurs when parts of the building fabric connect (namely junctions and details), breaking the continuity of the insulation layer resulting in localised areas of increased heat loss. Correct design and installation of insulation will help to reduce the risk of this happening. Considering an off-site timber frame build solution like i-House by Roofspace Solutions is a fast construction programme for those seeking a speedy delivery and excellent thermal performance, reducing the amount of heat lost at thermal bridges.
All of these factors are under the umbrella of the fabric first approach, and if you are able to weave these into your self-build design you’re on your way to inhabiting a truly sustainable home. By prioritising the design of a low-energy build, you’ll be able reap the benefits for years to come through reduced running costs and a comfortable, warm home.
The Saint-Gobain Guide to the Future Homes Standard provides an overview of the goals for the Standard, and it explores a range of Saint-Gobain building solutions and services to help meet the requirements of the Standard as it is defined.