Greenhouses come in many varieties. You can buy a kit from a reliable DIY shop, hardware store or a garden centre. This could be a plastic-sheeted economy version or a high-end glazed version. There are many types of eco-friendly greenhouses.
In the worst-case scenario, you could hire a specialist builder to install the greenhouse of your choice.
What You Should Do
If you opt for the DIY route, first of all you have to make an honest assessment of your own DIY skills. Greenhouses, like many other buildings, need to be installed on foundations. You cannot erect them just as you would a doll’s house, straight on to the carpet or lawn.
So be quite honest with yourself. Can you dig a trench deep enough to install some good foundations? These may be bought outright or can be made by you by pouring concrete. Are you comfortable pouring concrete and do you have the space to mix it or at least for a concrete truck to arrive to deliver it?
If the answer to these questions is no, opt for a simpler and lighter greenhouse. The simplest version is a set of bricks or a small wooden frame supporting an upper frame that is overlain with a transparent plastic material. The foundation frame need only be about one metre high. This is sufficient to grow cucumbers during an average British summer. Large greenhouses with window walls need more than this.
Greenhouses these days come as kits, with metal, plastic or wooden frames, glass or plastic windows and a huge variety of electrical conduits and mechanical vents. Decide on what you want to use the greenhouse for and your budget before you opt for a particular kind of kit.
The Size Of Your Greenhouse
You do not need a high greenhouse if you are only going to grow early-spring seedlings for planting out in the garden in late spring and early summer. The same applies to growing herbs during the winter. But if you want to grow large tomato plants or sweet peppers, let alone chrysanthemums and dahlias, throughout the second half of the year and all the way up to Christmas, you need a greenhouse that you will be able to stand up in.
Once you have decided on the size and nature of the greenhouse you need, make sure that you have applied for any necessary local planning permissions. In some areas, even the erection of a greenhouse in what may seem to be someone’s private back garden may need planning permission, especially if it overlooks the land of a neighbour.
When you have all of the necessary permissions in place, make sure that you have all of the tools you need to build the greenhouse. The days are past when you only needed a saw, putty, hammer and nails. Many greenhouse kits will need to be assembled using power tools.
Such items are not always the expensive versions used by professional builders. Inspect a shop version of the greenhouse kit you intend to buy to make sure you will be capable of putting it together.
You should also inspect the greenhouse site for possible electrical and drainage conduits. A greenhouse of any size will need some kind of lighting and heating later in the year. The best option would be to ask an electrician and plumber for advice on this and hire them for the work.