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Subject: Re: Should I insulate my greenhouse?
From: "Laphan" <laphan@ukonline.co.uk>
Organization: [posted via Easynet]
Date: Mon, 20 Aug 01 03:43:03
Message-ID: <MOD$010819.10430@rec.gardens.ecosystems>



Should I insulate my greenhouse?

A greenhouse gives discerning gardeners many advantages in their battle with
the elements. A greenhouse will offer protection against wind and rain, and
when shaded it will protect plants from leaf scorch. Humidity and water
usage can also be controlled when growing plants under glass.

Cold greenhouse

Temperatures within an unheated greenhouse, however, are very much dependent
on what is happening outside. This is because the interior of the greenhouse
will be warmer than the temperature outside on bright and sunny days, but at
night and during cloudy days the temperature inside, (wind chill aside) will
be very much the same as the temperature outside. A greenhouse without some
form of artificial heat source such as the one described is usually referred
to as a "cold greenhouse". This type of greenhouse has limited advantages,
and is used mainly to extend the growing season by promoting early growth in
spring and extending the ripening period in autumn. Cold weather and severe
frosts, however, will penetrate the cold greenhouse, rendering it useless
for storing things such as tender plants, tubers, corms or bulbs or for the
early propagation of seedlings. For this purpose some form of heat source is
required

Cool greenhouse

When a heat source sufficient only to keep frosts at bay is supplied, this
type of greenhouse is called a "cool greenhouse". To keep a greenhouse
frost- free need not be expensive, especially if some of the following steps
are taken. Try to site your greenhouse where it is sheltered from prevailing
winds and where the winter sun can reach its longest side. Reduce draughts
by filling in gaps with putty or similar material. A full greenhouse
maintains its heat better than an empty one so where possible leave full
water containers in the greenhouse so that the heat absorbed during the day
can be slowly released at night. Partitioning the greenhouse so that only a
small portion of the structure need be heated is another way of saving
costs. Insulating the greenhouse will certainly improve results but savings
where a cold or cool greenhouse is concerned would have to be worth the
initial outlay.

Hot greenhouse

Much higher minimum temperatures are required if the greenhouse is to be
used for all year cultivation, the growing of tender plants, or for the
early propagation of bedding plants. This type of greenhouse is referred to
as a "hot greenhouse". In this type of greenhouse fuel efficiency is of
paramount importance, and since glass is a very poor insulator, every means
of fuel saving must be considered. A thermostatically controlled heater will
cut fuel bills but remember, the faster the heat disperses through the
glass, the faster the heater will have to come back on to maintain the
required temperature. Insulating the greenhouse can slow the rate at which
heat is lost through the glass, reducing costs and helping to reduce large
fluctuations in temperature.

Several types of insulation are available, but if the type you choose is
made of plastic, make sure it is UV stabilised so that it doesn't start to
deteriorate after just a couple of years' use. Also choose one that allows
the maximum amount of light possible to enter the greenhouse as light is at
a premium during the winter months. Fuel is set to become more and more
expensive as governments come under greater pressure to reduce greenhouse
gasses. After all it really doesn't make sense to pay good money simply to
contribute to global warming.

Author - K.R.McGrath inventor of the Insulite Panels greenhouse insulation
system

Tested and approved by:
Professor S Sharples - Sheffield Hallam University
Chris Day - Amatuer Gardening Magazine
Bernard Salt - Garden Answers Magazine

The tests carried out by Sheffield Hallam University showed fuel savings of
46%

Save money on heating costs and reduce your contribution to global warming,
whilst at the same time improving results in the greenhouse - buy our
Insulite Panels!

Email: info@insulitepanels.co.uk

Web: http://www.insulitepanels.co.uk