3 mm glass or 4mm

need so help here ,looking for our 1st greenhouse a 8 x 10 - hurcules or a rino, we can spend about �£1500 but do I go for a nice green hurcules or a plain finished rino but with the thicker glass . dont know if the thicker glass is realy necessary ,there will be a fence to the rear but the rest is fairly open . We live in the middle of a housing estate and the greenhouse will catch the prevaling west wind

 

Hi snoo, I'm not sure but unless the thicker glass is toughened I cant really see the point,
other than maybe the 4mm will be flat, whereas the 3mm will probably be a bit distorted that is.
I'm sure Paladin will be along later with the right info. he's our professional glazier. :D

 

both the 3 and 4 mm glass would be toughened and in single sheets , not concerned at distortion just is it worth the extra cost of �£200

 

Ah, well probably no distortion, greenhouse have moved on alot since I bought my last one.
3mm seems a bit thin to me to be in large sheets,I think if I was paying �£1500, I 'd go that bit extra and go for the 4mm.

 

I had 3mm in sides and 4mm in roof of mine, before I dismantled it. If glass is toughened tho' I think 3mm would be okay. However, might be worth sending paladin a pm if he doesn't see your posting.

 

Hi there!! Did someone call??? :D

Pete is right about the insulation values,not that much difference,not enough to worry about anyway.
If the largest sheets are no bigger than Dutch light size of 4x2ft then the 3mm toughened is fine,though I doubt they would be bigger. These days the largest size supplied is more like 2x2ft toughened or otherwise.
Toughened glass gets distorted anyway,4&3mm,so that's not an issue here.
Thicker glass is heavier for sure but I just double up on the glazing clips to hold the glass down in an exposed site...and a dab or six of clear silicone under each pane works wonders!

So I'm in favour of a nice green coloured PPC one...after all..that's what they are aren't they ??!! ... :D

 

The only thing which crosses my mind on this is that with 4mm glass there is 33% more weight on the frame, a factor to consider in regard to wind damage. If the frame is heavier then no problem (or if the frame is over strong for the 3mm glass).

 

Hi Snoo, go with the 3mm toughened, it`s unlikely that you are going to have Dutch Lights ( 56" x 28 3/4") so the weight problem does`nt exist. David.