The roof is glazed with large 4mm toughened glass sheets that sit neatly between preformed ridges running down each rafter. Powder coated aluminium capping is screwed down into the rafters, holding the glass in place and sealing them with rubber gaskets. At the top end the sheets sit under the aluminium capping – you can see these details in the image above.
At the bottom the panes rest against a ridge on the aluminium gutter, so water running down gets deposited into the gutter and never comes in contact with timber (right).
The roof is fully weather sealed and virtually maintenance free. Yet, if a pane should ever be broken, it is simply a matter of undoing a couple of rows of screws and it can be lifted out.
Running along the entire top of the roof is an ingenious ridge ventilator. It is operated by wax filled cylinders that expand when the temperature rises inside the greenhouse, opening the vents along the entire length of the ridge. Being the highest point where warm air naturally collects this is very efficient at creating good air circulation throughout the greenhouse. The open vents also act like an umbrella, so rain hardly ever gets in – important when you are trying to avoid rain borne diseases like blight.