With standard Elite Greenhouses there are built in bases which allow the greenhouse to be built on any surface, however if you wish to have your greenhouse on blocks, concrete or bricks a flat base is an essential requirement for a greenhouse to stand on. Swallow greenhouses, Eden zero threshold greenhouses and the Juliana range all need solid flat bases.
If your site is not flat and level you will not be able to construct the greenhouse as square and as well as possible. It may seem that the base work is a large part of the overall cost of a greenhouse project but it is also one of the most important aspects.
There are several options available for a base, however pavers are currently the most popular. We usually build a base 1 foot larger all round than the greenhouse, i.e. An 8' x 6' house would stand on a 10' x 8' base. Concrete is another option but can suffer from pooling water during damping down which could lead to slippery areas. Block bases are also used which allows planting directly into the soil. Please bear in mind that current advice is to replace the border soil or sterilise it every 2 - 3 years. Examples of block and paver bases are shown below.
Cutting corners with bases is not a good idea, however anyone with average DIY skills (and ideally willing help), can build their own base and save a lot of labour costs. We recommend for paver bases 4" of compacted aggregate and 2" of sand on top, with the thickness of the paver that entails digging out around 8" of earth to allow the base to be level with the original area. We work with local firms who we trust to work to our specifications and have proved they can lay bases correctly and without compromise.
One thing we always struggle with, along with everyone else in the industry is lead times. Any good builder or landscape gardener will be booked out for many months at the busiest times of the year. If you are thinking of a greenhouse base please try and plan well in advance as we will not be able to drop anyone onto a job at a week's notice.
This is a paver base we built for a High Eave 8' x 6' The customer specified a wider gap between the fence than usual so this house sits on a 12' x 10' base. Quite a wise move as cleaning access will be very easy.
This High Eave 8' x 6' sits on a block base to allow planting directly into the border soil. 3 pavers were laid as a path down the middle. This base is a very economical option.