Glass V Plastic

Lotus-eater

peter_the_piper wrote: »

We have a mix of plastic tunnels and glass houses. Glass may be more expensive but you only have to replace when broken. Plastic means a replacement sheet any time from 4 years to 8 years depending on quality of sheet used. Glass houses are easier to insulate and shade and I believe (but not totally sure) that that glass does not transmit heat to the outside of the house as quickly as plastic.

Pretty sure it's the other way round, glass loses heat faster than plastic. Although I doubt it often makes much of a difference.

demystified

Glass is heavier and makes the glasshouse less likely to move in high winds, plastic will go milky and deteriorate if it's not UV resistant. Plastic is more expensive I believe. It also scratches more easily.

If the glass is constantly breaking theres something wrong somewhere breakages have been very rare in all my glasshouses

calisto

Ahem, perhaps mischievous little scamps are the problem? Not that I ever threw a pebble at a greenhouse when I was a member of the Dennis the Menace and Gnasher fan-club (badges and all). Oh no!

DC Thomson comics of Dundee have a lot to answer for, not me guvnor!

alanobrien

peter_the_piper wrote: »

We have a mix of plastic tunnels and glass houses. Glass may be more expensive but you only have to replace when broken. Plastic means a replacement sheet any time from 4 years to 8 years depending on quality of sheet used. Glass houses are easier to insulate and shade and I believe (but not totally sure) that that glass does not transmit heat to the outside of the house as quickly as plastic.

Glass, at least the type we put into greenhouses has a much higher thermal conductivity than plastic (2 to 10 times depending on the type) essentially this means that a glass greenhouse heats up quicker than plastic but also looses heat quicker as it cools.

SailorSam

LincolnshireYokel wrote: »

you can get 2' x 3'10" twin wall polycarbonate sheets that fit greenhouse perfectly, but they're £8 a throw.

I got the twin wall plastic for my greenhouse from B&q, i thought it was expensive but 'cos i lived near to the local Comp i thought in the long term it would be worth it. And it's much easier to cut to size than glass.

alandbailey

To overcome similar problems I fitted 10mm polycarbonate sheeting over each glass panel - there is just enough room to secure outside with W glazing clips.
I did not replace any cracked/broken glass panes, just doubleglazed over them.
I obtained the sheeting from a builder on freecycle who was demolishing a conservatory and these were the roof panels - had to cut them down to size, of course.
I no longer need to put up shading or insulation inside - my greenhouse is no longer a cold house but a warm one.
moneysaving result!!!