From taking a 'fabric first' approach to heating and water waste systems, it's never been easier for your self build project to be green.
Image: Darren Chung
Currently, the built environment is one of the biggest net contributors to the UK’s carbon footprint, and a large percentage of these emissions can be attributed to operational costs. These come from the day to day running of the building once completed and ranges from heating, ventilation and air conditioning (HVAC) to lighting and electrical appliances.
However, with so many eco-friendly materials, low-energy consumption systems and efficient build methods available on the market, going green has never been easier.
Whilst many are beholden to a third-party developer to make these investments for them, which is seldom the case, selfbuilders have the freedom to install according to their own preference and specification. Indeed, to mitigate climate change, they have something of a duty to do so, acting as trailblazers for the wider housebuilding industry to follow. Over the last two decades, we have seen many Grand Designs take up this challenge to construct truly sustainable dwellings.
No matter the scale of your new build, there are a number of cost-effective, eco-friendly and efficient building solutions at the click of a mouse and tap of a key. Charlie Ayers, Managing Director of cavity wall system SureCav, gives you a few things to consider when initially approaching your project with a sustainable brief.
Eco building materials
Material choices are one of the most important considerations for a self builder seeking to achieve a sustainable, carbon neutral home. Understanding exactly what materials you are specifying is crucial, particularly as they relate to a ‘Fabric First’ approach. This concept has been gaining traction in the architectural community over the last year and, with upcoming changes to the building code, is set to become standard.
Essentially, ‘Fabric First’, implies maximising the performance of the build’s structural components, reducing dependence on mechanical HVAC systems, lowering operational costs and improve energy efficiency.
So, not only should you source products with strong sustainable credentials, including those made from recycled, low-impact materials, but also consider those which can help deliver optimum thermal performance to reduce carbon emissions.
Also, read the manufacturers claims carefully and look for terms such as, ‘delivering low U-values’, ‘super-high insulation’, ‘exploiting thermal mass’, ‘delivering air-tightness’, ‘solar gain’. These will offer a good indication of a high-performance brand. A great place to start is NBS (formerly National Building Specification) which, alongside its powerful product selection platform, NBS Source, it also has a rich bank of content on how to choose the most sustainable materials and components for your build.
Image: Soup Architects converted this listed barn in St Saviour, Guernsey, to create a four-bedroom home with a contemporary extension. All walls, floors and roofs were insulated to levels that surpass building-regulations requirements. Passive solar design was also a key factor in the overall scheme.
Alternative heating systems
As much as it would be great to suggest that passive solutions alone could keep a house consistently warm throughout the winter, in some parts of the country, this will never be the case. Equally, in areas of high precipitation, excessive moisture requires the need for mechanical heating solutions, beyond the fabric of the building alone.
The imminent phasing out of gas boilers and changes to EPC scores, bringing equilibrium to how gas and electricity are rated in terms of energy efficiency, is encouraging a sea change regarding central heating. Significantly, it is fostering a more sustainable approach.
Fortunately, a number of effective, low energy solutions are coming onto the market. One of the most publicised are ground and air source heat pumps which, despite a significant initial cost, deliver real value long-term. Furthermore, Infrared and solar are just two other emerging technologies which selfbuilders should definitely investigate should they want low carbon heating solutions.
Read more: A guide to air source heat pumps
Image: A pair of Victorian townhouses in Manchester were developed in line with the exacting Passivhaus Enerphit Plus Homes standard. Eco consultants Ecospheric kitted them out with recycled newspaper insulation, an MVHR system and PV panels.
Clearing the air
Air quality is another factor which has received increased attention, particularly over the last six months, during the COVID-19 pandemic, where many have begun to question both the safety and energy consumption of air conditioning systems.
To this end, passive ventilation systems have grown in popularity. These solutions utilise natural wind and organic hot air from the exterior to encourage airflow in the interior, resulting in the extraction of moist, stale air and replacing it with fresh air.
Not only are these systems easy to install, they will also significantly reduce energy bill, lower emissions and improve overall air quality in the home, for a healthier environment. Widely available, they are further enhanced when a ‘Fabric First’ approach is pursued.
Waste water systems
Recycling waste water is another quick and easy way in which to make a property work more efficiently whilst reducing your consumption of this precious commodity. There are many advanced grey water systems available which can repurpose used water for all manner of different tasks, such as clothes washing and toilet flushing.
Equally, smart attenuation systems are particularly useful, especially in areas of high rainfall. Not only do strategically placed SuDS (sustainable drainage systems) prevent flooding, they can be fitted with a reserve tank to collect storm water for future use, including irrigation of plants and crops.
Not only are you reducing your water bills, but you are also taking steps to mitigate potential pollution in our waterways, protecting natural habits and the environment.