Sustainably constructing garden buildings. Phil Kemp is introduced to Justin Murray of Qube Buildings and a whole new way of sustainably constructing garden buildings such as home offices.

Garden Office editorial

Justin Murray is passionate about environmental sustainability and especially in the home building industry. He and his colleagues have launched an inspiring and forward-looking initiative to bring environmentally friendly building techniques to the forefront – initially in easy to construct garden buildings but also with the longer term aim of widening their design and construction initiatives to the broader construction market.

“I am a qualified Passive House Consultant which basically is the gold standard of low energy housing. The frustrating thing is that if half the house builders applied half the amount of science to house building they would be producing such better quality housing that consumes almost zero energy to power it,” Justin enthused. “Using sunlight to heat, and using your own body temperature, your cooking, and your shower to heat the house. And this is the way that we have to go as a society. It is the only way to go. Capturing all of the sun’s energy to heat and energise the house is basic, it’s easy! You’ve just got to design the house right and build it the right way too.”

 Qube uses sustainably sourced high-performance materials for their modular constructions that are well-suited for constructing garden offices and studios.

 “We have developed a panel with a difference. Our Bio Structural Insulated Panels, or Bio-SIP Panels for short, have an outer skin made from hemp which is a very strong plant material forming two outer boards which sandwich inside insulation that is made from 100% recycled PET plastic bottles which can be recycled again at end-of-life – what is being called ‘cradle to cradle’. And 30% of the epoxy resin we use to bond everything together to make a rigid panel is plant-based. The panels are very strong and thermally they perform very well and are lightweight compared to say wooden panels.”

Sustainably constructing garden buildings

The panels, which lock together without the need for bricks or cement, are delivered as flat packs that are quick and straightforward to erect. The building’s windows and doors click into place and only basic tools are needed to secure the floor and roof.

“For the structural material hemp is amazing. Every ton of hemp takes out 1.6 tons of CO2 from the atmosphere whilst it is growing. And as well as extracting all of that carbon out of the atmosphere it nourishes the ground as well. In Henry VIII’s time all farmers had under law to grow at least a hectare of hemp just to enrich the soil. It makes you wonder why are we not using hemp more as a construction material.

Hemp is the future for sustainable construction building material

There is another product called hempcrete which is basically hemp and concrete mixed together. It’s only a very small percentage of concrete and the concrete is obviously not a sustainable building material but for this it is fit for purpose. Hempcrete is much stronger than concrete and it is a fraction of the weight. And moving forward we will be using more of these materials. And it’s not a modern innovation as they have been using hemp for centuries for a whole cross-section of building materials. The hemp we use is grown in Yorkshire. Go to the British Hemp Alliance’s website to find out more about this amazing agricultural crop.”

“In my training for Passive House Consultant I realised how to make a panel that is thermally very efficient. There is no what is called ‘thermal bridging’ in our panels. Thermal bridging is basically where you have a cold side, so the panel facing out, and you have a piece of wood in-between as part of the structure. And what happens is that cold air from the outside will transfer through the wood to the inside – which is the thermal bridge. Wood is not thermally efficient. So our panels are what we in the industry call ‘thermal bridge free’.

Jaffa and Justin

Qube started by focusing on building garden offices because of the increased demand due to the work from home ethos developed during the Covid pandemic. Their panels can be used to build outdoor structures for a wide range of activities including cabins, glamping pods and studios. And they are investigating ways where you can design your own building online and then for this to be flat packed and shipped out to you ready to be installed.

And Justin emphasised just how seriously they take their environmental sustainability at all levels. “We have designed it so that there is zero waste on site too. The pallets we deliver the panels on are part of the structure and all of the packing materials we use to protect the unit while it is in transport are used within the building.”

Phil Kemp is a Godalming-based writer and photographer.

FIND OUT MORE on vantage point magazine :

The British Hemp Alliance

For more information on our Bio-Sip panels please visit here. For a list of our garden building kits visit here.

Mini Cart