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An important rule of thumb is NOT to choose a greenhouse model that is too small. After installing their new greenhouse a lot of first-time buyers experience...

Whether you should opt for glass or polycarbonate as your greenhouse filling depends of what you are trying to accomplish...

The location of your greenhouse is a decisive factor in regards to the climate inside the house as well as other things. If your goal is to accomplish...

Before you setup your greenhouse it is essential that you provide a strong and stable foundation. Whether you opt of a do-it-yourself approach or use a...

Glass vs. Poly for the Greenhouse?

For decades, hobby greenhouses were constructed from an aluminum frame with glass as a glazing material. Most Juliana greenhouse models come with a 3 mm split glass as standard.

Glass vs polycarbonate for the GreenhouseIn recent years, glass has increasingly been replaced by polycarbonate insulation panels.

It is easy to understand why!

Polycarbonate sheets are constructed in 2 layers with embedded air channels and this construction provides many advantages over glass (10 mm poly are built in 3 layers).

Most professional growers use today polycarbonate instead of glass

Facts: Glasshouses

Light penetration

  • (+) It is possible to look through the glass and watch the plants.
  • (+) In the spring when there are few hours of light, the plants need all the light they can get.
  • (-) During summer there is a need for shading, either blinds or shade pasta, and then you can no longer see into the greenhouse.


  • (-) There are significant temperature differences between day and night. This can inhibit plant growth. It is possible to compensate for temperature differences by means of window, shade / shadow pasta and warmer. Even in summer it may be necessary to heat the greenhouse.
  • (-) The large temperature differences can cause damage similar to that actual frost damage.
  • (-) Heating of a greenhouse with glass without insulation is expensive and almost impossible during winter months.


  • (+) Glass does not decompose by sunbeams.
  • (-) The glass can easily break eg. by small stones from a lawnmower, falling branches or children playing.


  • (-) The glass should be treated with caution when installing it.
  • (-) The glass may break during transportation, which may delay the installation.

Facts: Poly Greenhouses

Light penetration

  • (+/ -) 4 polycarbonate sheets are not easy to look through. This actually improves with 6 and 10 mm polycarbonate where you are able to actually see the plants.
  • (-) In the spring when there are few hours of light, the plants may suffer from the absence of light. This can be adjusted with artificial light.
  • (+) You do not need extra shade using shade curtains or shade pasta.


  • (+) During summer when the sun gets really hot poly protects not only against the sunrays, but it also stabalises the core temperature of the greenhouse whcih provide your plants the best growing conditions.
  • (+) Provides less radical temperature de/increases and extends the greenhouse season with 1-2 months compared to a greenhouse with glass.
  • (-) Greenhouses with polycarbonate are often better isolated than greenhouses with glass. This leads to the emergence of a greater humidity because window operators opens later than a greenhouse with glass. This can be solved by frequent ventilation.
  • (+) Heating of a greenhouse with polycarbonate is cheaper than a greenhouse with glass. To overwinter plants, 10 mm polycarbonate is recommended.


  • (+) Polycarbonate sheets have a UV protected surface against the sun's destructive rays. Juliana provide a 10-year warranty against yellowing of the plates.
  • (+) Polycarbonate sheets can easily tolerate small stones from lawnmowers, falling branches or children playing. So enjoy that extra safety in your garden.


  • (+) polycarbonate sheets are easy to install, there are no sharp edges that can cut on.
  • (+) polycarbonate is very rarely damaged during transportation.

10 Good Reasons...

10 good reasons to choose Juliana
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