The Swallow range of wooden greenhouses are made from Thermowood, which is manufactured from quality redwood pine. The process involves kiln drying the timber which is then put in a special oven, where a powerful compressor removes the air. The temperature is raised to 215°C, which bakes the timber.
This natural, chemical free process seals the capillaries, destroys resins and proteins, and stabilises the timber.
The benefits are that it can be left untreated as all bacteria is killed, resulting in an improved durability against decay. It also gives a consistent colour throughout the wood and paints really well – the finish lasting up to three times longer than it would otherwise.
The frame is also protected by a strong plastic ‘U’ section damp barrier.