Green Homes Network

Grant built his own energy efficient home near Inverness during 2018 and 2019. It has an impressive Energy Performance Certificate (EPC) rating of B. The modern design is built to Scotframe’s Val-U-Therm kit specification and the timber, which is fitted with K Rend external cladding, helps to keep the heat in.

Looking for inspiration

Before starting his build, Grant attended a few Home Building and Renovating Roadshows in Glasgow for inspiration. He also did a lot of online research and spoke to installers for recommendations.

Grant had previously helped to upgrade his local community hall by installing an air source heat pump and insulation; his research on this project led him to consider similar technologies for his self-build.

Grant initially looked into installing a ground source heat pump because he had adequate land around his property. However, he was slightly alarmed by the amount of internal equipment required and wasn’t sure if his planned utility room could accommodate it. After seeing how quiet and efficient a modern air source heat pump could be, Grant contracted Dingwall-based Airsource1, the same installer that was used for the community hall, to install an air source heat pump instead.

A mechanical ventilation heat recovery installer also suggested that Grant make his property as air-tight and heavily insulated as possible.

Installing the heating and ventilation

In March 2019 Airsource1 installed an Ecodan Standard 300l water cylinder. This was followed by an Ecodan air source heat pump, in April. These two elements only took a couple of days to install while a plumber carried out a lot of the pipework.

Grant’s mechanical ventilation heat recovery system, a Zehnder Comfoair Q350 system, was installed around the same time and commissioned in May. The taping and foaming of the ducting system took around a week to install, but the ducting was installed in only two days.

Grant’s heating project came in on budget. However, Airsource1 told Grant about the Home Energy Scotland Loan, funded by the Scottish Government, which would enable him to borrow £7,000 interest-free to help spread the cost of his heat pump.

A green and warm home

To keep the countryside noise to a minimum, and keep in as much heat as possible, Grant installed triple glazing. His home is now so cosy that he says during the winter he is welcomed by a warm blanket of heat when he enters through the front door. He experiments with the Heatmiser thermostats, from Optimum Underfloor Heating, by setting different time slots depending on his household needs.

Grant’s two-person household consistently uses around 7,000kWh of electricity each year. He tries to keep energy use down by setting water heating timers during the day when the residual temperature is warmer. He has also invested in A or A+ rated appliances where possible. Grant thinks his energy bills seem high, but when he compares his bills to friends and family that use oil, gas and storage heater set ups, he isn’t so concerned and he is aware that market costs continue to rise anyway.

In the future Grant says he may consider generating his own electricity to offset the rise in his energy costs; these have doubled from £0.06 per hour, when he moved in, to £0.12 per hour today. Grant didn’t have the budget to install solar photovoltaic (PV) panels when he was building his home but he’s now considering installing these, combined with battery storage, to offset the higher costs of the air source heat pump during cold-weather. He says he would also consider generating electricity with a small-scale wind turbine when the technology improves for smaller scale domestic set-ups.

Grant received a discount on his self-build mortgage deal thanks to his home’s high EPC rating. He also applied for annual Renewable Heat Incentive (RHI) payments and will receive £620 each year for seven years (new applications for RHI ceased in March 2022).

Grant expects to pay £100 to 120 every year to service the mechanical ventilation heat recovery system and air source heat pump. However, he expects the only maintenance required will be fitting new filters and checking vents.

Grant says that air tightness is key for any new build or complete renovation: “whatever your source of heat, try to keep it in as much as you can”. Grant also suggests making sure your builders and joiners understand this goal. He has achieved superior air tightness in his home, but thanks to the ventilation system it is a fresh living space.

Feeling inspired?

If you too want to research different types of renewable technologies, our Home Renewables Selector will help you discover your options and calculate your savings. You can also use the Renewables Installer Finder to find accredited installers in your area.