Quality housing is one of the cornerstones of any decent society.
In the U.K., such is the demand for housing that the government has set itself the ambitious target of building 300,000 new homes a year by the middle of this decade.
And with the issue of climate change high on the agenda of government, architects, housing developers and homeowners, there is the added impetus to ensure that all new homes are designed and built—and able to operate once delivered—to have all the features of a sustainable house.
It’s not just new homes that need to be energy efficient, however. Much of the U.K.’s existing housing stock, some of it hundreds of years old, loses heat into the atmosphere, thanks to ill-fitting windows and walls and roofs that have little or no insulation.
Retrofitting eco-friendly house features into such homes is a multimillion-pound industry, and it is easy to see why when one considers where the problem lies.
Reducing emissions with eco-friendly house features
According to the Energy Saving Trust (EST) around 22% of U.K. carbon emissions come from homes.
Efforts are ongoing to ensure eco-friendly homes are designed to not waste energy through remedies such as better wall insulation, draught-free windows and heating systems which have been designed to be both more efficient and have less impact on the environment.
The U.K. government recognised this problem last year, when it launched the Green Homes Grant, inviting homeowners to apply for money to upgrade the energy efficiency of their homes and potentially save up to £600 a year.
But this £1.5bn scheme was withdrawn in March 2021 amid accusations that it was rushed through and not properly though out.
The rationale for this kind of financial assistance is clear, however; two-thirds of homes in the U.K. fail to meet long-term energy efficient targets.
According to research, more than 12 million homes fall below the C grade on Energy Performance Certificates graded from A-G.
This lack of eco-friendly house features means homeowners are not only spending more than they need to on energy bills; they are also pumping tonnes more CO2 into the atmosphere than necessary.
Efficiency and sustainability – 5 features of a sustainable house
Methods to improve the energy efficiency and sustainability of our homes come in many forms. Installing insulation is one of the more commonly carried out jobs on existing housing stock, while new homes are constructed to be more airtight.
According to the findings of a U.K. government consultation, “What Does It Cost To Retrofit Homes?,” the costs for insulating party cavity walls ranged from £25-£30 per square metre, or £350 per home.
Internal wall insulation can cost between £55 and £140 per square metre of wall, or £5,000 to £10,400 for a small semi-detached home, compared to external wall insulation costs from £55 to £180 per square metre or £7,000 to £9,000.
According to the EST, installing solid wall insulation can cost between £8,000 and £10,000 for an average-sized home, and result in savings of between £105 and £375 annually, depending on the property type.
The EST adds that CO2 savings of between 425kg and 1,540kg a year can be achieved through such work.
Then there is how homeowners actually heat their homes. The move to reduce carbon emissions will see gas-fuelled systems phased out of new builds in the U.K. by the middle of the decade, as part of the Future Homes Standard.
Increasingly heat pumps are being used. Regarded as a “clean” energy, heat pumps are considered “fit-and-forget” features of a sustainable house.
There are two types: ground source and air source. A ground source heat pump, featuring pipes that extract latent heat from below the ground, can typically cost between £15,000 and £16,000, while the running costs for a four-bedroom house equate to £500 a year.
Alternatively, homeowners can install an air source heat pump, which looks like an external air conditioning unit, extracts heat from the air and runs it through a heat exchanger.
Air source heat pumps can cost between £10,000 and £11,000 and cost just over £700 a year to heat a four-bedroom house.
Another eco-friendly house feature with which many will be familiar is solar power. A typical solar panel array of 12 to 16 roof-mounted panels could cost between £5,000 to £8,000.
LED light bulbs
There are other steps people can take to increase their homes’ sustainability credentials that aren’t expensive, but which over a period of time can offer savings.
LED light bulbs consume less energy than conventional bulbs, yet they are just as bright and help to save on electricity usage and bills.
Draught-proofing one’s home by sealing up cracks and gaps around windows and doors can help keep heat in and save energy, while insulating pipes and hot water tanks can keep water warmer for longer.
And smart thermostats, which automatically adjust the heat in a home depending on the usage and outside temperature, will also save on the bills.
Homebuilders recognise the growing demand for greater energy efficiency and for homes to have less of an impact on the environment.
What are the features of sustainable house design?
Using modern methods of construction, such as timber frame techniques, self-build eco-friendly homes can be constructed for anywhere between £35,000 and £200,000.
One of the best known low-energy design standards is Passivhaus. Buildings built to Passivhaus standards provide a high level of occupant comfort while using reduced amounts of energy for heating and cooling.
The aim of designing a house to Passivhaus standards is to “dramatically reduce the annual carbon emissions of a building” through its size, shape and orientation, good heat retention, airtightness, natural ventilation and heat recovery systems.
Again, elements such as membranes throughout to ensure air tightness levels, smart ventilation, efficient glazing—often triple—and drainage and water reclamation technologies can be employed to reaffirm a building’s eco credentials.
Architects, developers and self-build enthusiasts can benefit from using Bluebeam Revu to deliver a sustainable house.
Clients using Revu for such schemes have seen them being delivered 25% more quickly, productivity gains of 60% thanks to streamlined communications and more than 1,000 hours saved by not using paper-based processes.