Allotment Gardening Advice Help Chat

Chatting => Design and Construction => Topic started by: Wavertree Red on May 01, 2011, 20:08

Title: Greenhouse Glass 3 or 4mm?
Post by: Wavertree Red on May 01, 2011, 20:08

Hello,

We've just acquired an 8x6 aluminium greenhouse....but without the glass.

A friend of mine is a glaser and has a LOT of spare 4mm glass he'd cut to shape for me but is adamant that 3mm is required as the clips would break anything fatter.  Is this the case?  He doesnt get much 3mm going spare and obviously Im trying to keep the costs down.  Also, is 3mm recommended because of its light transmission?

Any advice appreciated.

Thanks

Title: Re: Greenhouse Glass 3 or 4mm?
Post by: trev_pulsecity on May 01, 2011, 21:03

If it's the basic aluminium clips I would have though 4mm would be ok.

Certainly I have seen my dad put the odd 4mm pain in my gran's greenhouse.

Though loading the whole thing with 4mm might be different. It weighs more and where the panes of glass overlap it would be 8mm instead of 6mm. I guess you need to get a handful of samples first and try it, it could be ok.

Title: Re: Greenhouse Glass 3 or 4mm?
Post by: alancas on May 02, 2011, 11:45

i'm a glazier also he is right about the clips but you could use silcon to bed the glass on the only problem if the glass breaks in the future it's a bit harder to get out, to hang the thicker glass get some lead strips and beat with a hammer until it gets thinner this can used to support the glass until the silicon goes off the lead can be fed between the overlapping glass and bent around it snip off excess with scissors, hope this helps.

Title: Re: Greenhouse Glass 3 or 4mm?
Post by: ex-cavator on May 02, 2011, 12:55

Is the weight going to be a problem? Glass is very heavy - a whole greenhouse glazed with 4mm instead of 3mm will weigh a third as much again - will this be too much of a strain on a fairly flimsy frame designed to take just the weight of 3mm glass - particularly when it gets windy? :unsure:

Title: Re: Greenhouse Glass 3 or 4mm?
Post by: Wavertree Red on May 02, 2011, 17:35

Thanks for the replies.

I think I may just play it safe and get the 3mm glass.  There's plenty on ebay for around £1.20-£1.50 a sheet.  I'll just wait for some in my area.

Cheers

Title: Re: Greenhouse Glass 3 or 4mm?
Post by: trev_pulsecity on May 02, 2011, 21:20

Myself, being a cheapskate, I would get some 4mm pieces if they are free and see if its possible with the existing clips.

I can understand if you think its not worth while though and I am not exactly a greenhouse expert. I am yet to get one myself.

Title: Re: Greenhouse Glass 3 or 4mm?
Post by: Paul Plots on May 02, 2011, 22:33

Robinsons greenhouses are glazed with 4mm toughened glass (full sheets so no over-lapping) and some other makes with 3.3mm also toughened but again full sheets.

If you know the make of your greehouse give it a google to see if you can find a supplier as they may offer the same greenhouse with the heavier glass.

Generally agricultural glass is the lighter weight thinner stuff.

Title: Re: Greenhouse Glass 3 or 4mm?
Post by: alancas on May 03, 2011, 17:51

futher to my earlier thread i have glazed many greenhouses in 4mm glass where they should be 3mm and have no problems, why pay for more when you have some but that price you quoted was very good for 3mm glass.

Title: Re: Greenhouse Glass 3 or 4mm?
Post by: 8doubles on May 03, 2011, 18:36

If you are using steel W clips on the roof then the 4mm glass will be ok and stronger in wind ,hail or frost. The rubber sealing strips should just compress a bit more.
You may need to get 4mm S clips for the joins on the walls.