Timber
We use sustainably sourced, FSC certified, high-quality wood to construct and clad our Bonnis. It all comes from Denny’s family timber business, run today by his two brothers and in its 50th year of business. The timber goes through a kiln drying process to reach the necessary average moisture content, followed by a vacuum pressure treatment impregnation - a preservative process that enhances the timber's protection. 

Corrugated steel
In a continued effort to reduce our carbon footprint we use corrugated steel for our roofs and walls. A question we are often asked is ‘are steel roofs good for the environment?’. The simple answer is yes. Unlike most materials, steel is the only material used in construction that can be 100% recycled and re-used. Steel lasts longer, the material is better defended against the effects of nature and the environment, reducing the need for repair work and new materials. With its unrivalled recyclable properties and low environmental impact, it is our preferred choice of material. 

Bases
We like to construct our outbuildings in a way that avoids concrete entirely, putting our outbuildings on small stilts. This is a friendlier approach for your garden’s eco system too, allowing rainwater to run off into the soil. 

Treatments
All timber treatments and paint are water based and we use dry paint for our powder-coating. This ensures we have a smaller environmental impact compared to solvent-borne paint. This also allows for better air quality within our Bonnis.

Recycling
90% of our waste is timber and steel. We use the timber to heat the workshop and the steel and remaining waste is recycled where we can. We work hard to add as little as possible to landfill.

Energy
Our outbuildings allow you to choose your preferred method of energy use (solar, wind, biomass), offering off-grid and on-grid set-ups and an ethos of maximum energy efficiency. We can install a combination of technologies such as solar, battery and generators to supply electricity completely off-grid.

Doing our best…
The look, feel and impact on people and the planet matters to us and so we work to achieve as close to Passivhaus standard as we possibly can. To do this we use lots of insulation, fresh air, natural daylight, and the sun to create high performing buildings that maintain a constant temperature all year round. We care about every single product we use, and where they come from. In a drive to be as kind to the environment as possible – and to support local businesses - we aim for our suppliers to be within a 10 mile-radius of Bonni HQ. The sustainably sourced wood comes from Denny’s family firm, just 3 miles away. Windows, doors, paint and metal all come from firms in neighbouring towns and villages. We can’t always get everything we need on our doorstep so occasionally we do have to go further afield to get the best materials. We are continuously working with our suppliers to increase the amount of environmentally friendly and ethically sourced components for our Bonnis.