If you are thinking of investing in a greenhouse, it is essential that it has a sturdy, level and square base. Nathan James Dodd answers some frequently asked questions.
We're often asked what makes the best greenhouse base and floor, and whether they are difficult to construct, here we answer some of your questions.
Do Greenhouses Need A Base?
Yes, do not place a greenhouse directly on top of soil or turf.
Don't All Greenhouses Have An Integrated Base?
Many greenhouses have a built-in base as with the Elite and Juliana ranges, with other freestanding greenhouses such as Halls, Vitavia and Eden they are an optional extra. Even with a base, a greenhouse needs to be located on firm foundations.
Can I Build A Greenhouse Base?
You can, without much difficulty and with few tools.
What's The Best Material To Use?
Pressure treated 4in x 6in timber (4in x 4in for small greenhouses) or paving slabs are ideal.
How Do I Start?
Pick the location, dig down to solid earth and level off the area, clearing away all stones and vegetation. Note the outside dimensions of the greenhouse (measure them yourself, published dimensions are approximate).
If you are using timber, cut the lengths of wood to size, arrange them on the ground and fix together, making absolutely sure everything is level and square i.e. the dimensions diagonally from corner to corner must be equal.
How Are The Base And Greenhouse Secured?
First use ground anchors to secure the base, then bolts are best to fix the greenhouse to the timber base.
How Are Paving Slabs Used?
Dig out a spade's width to a depth of 5in - 6in around the edge. Fill the bottom 3in - 4in with rubble, hardcore, stones etc. and crush it in. Either add 2in - 3in of concrete mix on top or add a few more smaller stones, firm down and top with 1in sand. Lay the slabs on the sand and then fix the frame to them.
What Flooring Is Best For A Greenhouse?
Avoid concrete as water will have nowhere to drain. That's why paving slabs on top of hard core and sand are preferred, as they are easy to lay and water can escape through the gaps. You can also think about bricks, and gravel on which standing water will not collect.