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We manufacture and supply quality polytunnels in easy to assemble kit form.
We also supply accessories for polytunnels. We offer a friendly and helpful service
and will do all we can to make sure you receive the polytunnel that suits your
requirements.
Our customers include gardeners, allotment holders, horticultural enthusiasts
and specialists, small holders, nursery growers and farmers.
You may find the following links useful:
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Types of Polytunnel
in Polytunnels introduction |
The basic structure of a polytunnel (hoophouse) is extremely simple,
but there are a few variations on the basic theme. As well as ‘regular’
ones, there are other types of polytunnel including rigid panel
models, which offer much better insulation. If you’re a practical
type, you could also choose to make a tunnel yourself using rigid
plastic piping and purpose-made poly sheeting.
Having made the decision that polytunnel ownership is for you, the
temptation is to rush off and order one straight away. Catering
for customers who do exactly that, there are some friendly-looking
sellers around who keep everything looking very simple and offer
you a choice of only a few different kits. Don’t be fooled;
this simplicity is for their benefit, not for yours. At best you
will miss out on some of the choices that make polytunnels such
a flexible asset: at worst you will end up with a completely unsuitable
product. (The Polytunnel Handbook, A McKee & M Gatter, 2009)
The basic structure of a polytunnel is extremely simple; a row of
hoops fixed onto stakes, a ridge-pole, a door frame or two, and
some means of securing the cover. But given just how simple the
concept is, there are quite a few variations on the basic theme.
Without going into too much detail about accessories, here are the
main types of tunnel.
Regular tunnels
A basic polytunnel is a single-span structure. Avoid models without
straight side-sections if you can; curved sides create an area at
each side where it is awkward to work, because of the lack of head
room. This is not important in very wide tunnels. Always opt for
doors at each end unless your tunnel is very small, because ventilation
is your main defence against moulds and fungi that can be troublesome
in humid conditions. If you choose a regular polytunnel, you have
to choose between two methods of fixing the cover in place; trenching,
and fixing to a base rail.
Trenching is the least expensive option and gives an extremely strong
result, with the tension on the cover provided by burying the edges
into the soil. However, it requires digging a 30cm x 30cm (1' x
1') trench all the way round the tunnel footprint – no joke
in heavy or stony soil. Tunnel manufacturers tell us that it is
very common for customers to telephone to ask for a base rail kit
once they realise how much work trenching in is going to be!
Base rails, clamped to the tunnel uprights at low level, offer a
way to fix the cover to the tunnel frame rather than to the ground.
This is a lot less work, but the loss of strength to the tunnel
structure has to be offset by concreting the corners of the frame
in place, or by using ‘anchor plates’ which clamp onto
the uprights.
Solar tunnels
Solar tunnels offer a standard straight-sided tunnel design, but
the cover is quite different. Instead of being wrapped in a single
sheet of polythene, their tunnels are clad in modular sections of
double-layer film reinforced with green nylon mesh. This means that
they are more resistant to damage and insulate better than traditional
film, and look better too, but light transmission is poorer. The
modular design makes it possible to extend a solar tunnel without
re-skinning the rest of it, but the price difference between solar
and regular tunnels probably negates this advantage.
small Keder house
Rigid panel houses
A successful hybrid between polytunnels and greenhouses, these structures
use a variety of polytunnel-type frames to support rigid plastic
panels. The best of these are of dual-wall construction with embedded
bubbles trapped between the layers (marketed in the UK as Keder
houses), giving a remarkably strong cladding that insulates better
than polythene or glass. The drawback, however, is the considerable
cost.
Self-build tunnels
Building a tunnel from rigid plastic piping and lumber is not difficult,
although the action of ultraviolet light will ultimately make the
piping brittle. There are no shortage of accounts of how people
approached the problem on the internet, and we give a step-by-step
guide of how to make a simple and strong tunnel in The Polytunnel
Handbook. Once again bear in mind how the whole structure will be
anchored to the ground, as if you get things wrong you could find
yourself flying the most expensive kite you have ever owned!
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