Scottish Rock Garden Club Forum
Cultivation => Cultivation Problems => Topic started by: newstart on December 06, 2009, 09:45:09 PM
-
I am thinking of biting the bullet and buying a glass greenhouse. I seem to remember on reading some of the forums a while back that it was said that removing some of the glass panes made the greenhouse more accustomed to there surroundings. Can this be cleverally done to prevent other panes falling out in high winds. I thought to cut down the wind factor in replacement of each pane removed I could put some green shading windbreak netting so the wind would not come through so violentally. I am not in a really exposed location but it suprising how fast these gusts build. Any simple advice would be handy thanks!
-
David, I do think you will find a million and one reasons why a glass house is a good idea, when you do buy a glass house. :D
I'm not sure about the reasoning behind removing glass to keep the glasshouse more stable in wind. I wouldn't have thought that was the case. Certainly many of us do remove panes along the sides in the summer to help keep a good flow of air round alpines and other plants that might not appreciate the heat build up and stale air that might otherwise result, but I would guess that nearly all of us who do so, will replace those panes for winter.
Reason being that with greater wind speeds and strength likely in the winter, there is more chance of panes being blown out of the house then if there are gaps to begin with. If a really bad wind storm blows up in the summer that would also be a chance, but less liable to happen then. In winter, even though our glass house doors are nearly always left open, we do close them in very windy weather, in case the wind rips in through the door and straight out through the glass!
A cracked pane of glass can similarly be a risk in high winds to allow the wind to enter the glass house and then cause havoc as it seeks a way out again. :o It is sensible when siting a glass house not to have the door facing the direction of the prevailing wind for that reason.
That being said, I hope I don't sound like every glass house is just waiting to blow apart in the first breezy day! A standard aluminium glass house, properly assembled on a decent level base, can be perfectly sturdy and last for a great many years without incident or accident. I would not think your idea of windbreak netting as an aid to reduce wind travel is a good one.
Hope this is some help!
-
In a sheltered garden I have a 12'x8' glass/aluminium greenhouse with the glass removed from the sides at bench height. I also have one vertical run removed at the end without a door. I must empahsise that the greenhouse is sheltered from N, S and W winds by buildings, tall hedges or fences within a few metres but it has survived thus for 12 years with no damage. I do not replace the glass in winter ... so I cannot grow plants which cannot cope with a bit of frost.
-
Tony, I didn't know you managed to keep the glass out all year. As you say, this is in a sheltered spot, of course.
-
The aluminium frame of a greenhouse is very unstable and it requires the glass to give it rigidity. Having said that, in summer we remove severel panes of glass from each gable end of one of our houses to improve ventilation and replace them for winter.
With the second greenhouse I did not put any glass at all in the gabel end! I made up some wooden frames and covered them in green mesh and fitted these in place of the glass panes. This gives the rigidity but allows much more ventilation. The door of this house is treated similarily.
-
I quite forgot to say :-[ that when we remove the panes of glass we replace them with pieces of sturdy weldmesh which helps stabilises the aluminium framework.
-
here is a pic from my greenhouse - I can lift one complete side ....thats perfect for the ventilation !!!
On the other side are also all windows open ( from middle of April until end of October )
The roof has on east side also 3 windows which are open the whole summer - in winter I use automatic opener for the roof and the east side ....soon I have more than 10 ° the windows open .
Sometimes I use in winter a fan on the ground area -special when I have watered.
I think the most importet for my plants ( many cacti and bulbs ) is a lot of fresh air
Never had a problem with the wind or storm !!!
this are older pics from 2007 ......in meantime I have build tables ( outside ) so I can grow my shade loving plants the whole summer on the east side - this area is now protect for to much sun with a shade net
Hans
-
Now this is what I call well ventilated Hans !! ;)
-
I like what you have done
-
I like that too and it looks the perfect solution! One day when I have one built to my own specifications...
Meanwhile - My 7m x 2.5m wooden greenhouse has a large pane removed in the end opposite the door. This allows a through-draft and I think it is essential given that I just have standard ventialtion in the rest of the structure. I have a big piece of thick acrylic which bolts onto the frame to cover the hole in storms & hard frosts. There is galvanised mesh over this and all the vents (inlcluding a false mesh door inside the real one) to exclude the wildlife.
-
Hi Maggie and anyone else who got confused. When i say that the greenhouse would be more accustumed to the surroundings i mean that for the alpines they need more ventilation like the ones which grow outside, rather than making the structure more stable. It certainly would not make the structure more stable thats for absolute sure. Ho ho!
-
Hi David,
I agree with Hans a roof shelter with part sides rather than a conventional greenhouse is more useful. I have two parts to my commercial greenhouse. One part is just a roof with 3 open sides and one against the proper greenhouse. I use this all the time for my young plants where as the greenhouse proper doesn't have any plants in it, just potting benches :) .I found that it got too hot in the summer and wasn't much use as frost protection in the winter. For propagation I now use a double bubble tunnel which I heat and doesn't have many plants in it in the summer, I am planning an extension to the shelter with a bubble polythene greenhouse with drop down sides (very expensive) You will find if you buy a normal greenhouse from the likes of B & Q it is best to adjust it with lots of ventilation or it will be like an oven in the summer. As you can see forumists are great inventors maybe you can copy some of their ideas. A lot of commercial tunnels have net side, I don't know if you can get small ones, maybe that is a good idea as well.
Susan
-
With reference to B & Q and other large shopping giants, I am always tempted by the design of those trolley shelters. Many of the larger ones would make unbelievably sturdy and practical alpine houses - though the cost would, of course, be quite prohibitive (and neighbours might object to any introduction)? :D
-
I also meant to ask about the toughened glass greenhouses. The one I was thinking of buying has toughened glass from top to bottom vertically. I am not sure about the roof this might be individual panes. I thought this could be a good option as there would then be no glass to remove away from the other panes on removal and replacement and less chances of accident with this with the winds. Also one single vertical piece of glass would be easier to erect I would think. I of course appreciate the fact that the 60cm x 60cm panes may give better control over the ventilation in winter if only a 1-3 are removed. I would probably just have the door open in winter if not windy and 2 vents at the top if particularly windy.
Also when it comes to shading in summer does the galvanised mesh ,which is attached to aluminium with wood frame, get covered with shading material. If anyone can provide a photo of how the wood frame attaches over the aluminium with mesh then I could guess the rest with how shading goes on behind this. If not I could always ask in summer again when the mesh and shading is on. Also how what mm or cm gap is there between the mesh and is it rigid or bendable.
thanks for the very helpful answers so far - all excellent!
-
David, the weldmesh we use has approx 2cms square mesh.
-
Good idea Cliff. A lot of companies are making smoking shelters now a days :-\
Susan
-
David, I think using non toughened glass gives you more flexibility in removing individual panes without impinging on the rigidity of the structure. (ie taking into account an 8x6 aluminium house the side elevation would give you 12 individual panes of non toughened glass per elevation and you could take out a few of these as well as adding some louvre vents. Toughened glass would give four very large panes per elevation) Or have I confused you further?
-
We have a lot of bike sheds similar to that 'trolley shelter' design on campus and like you Cliff, have wondered about them.
-
No David that is a fantastic answer thanks! On a cold or mild summer day it would still give good ventilation if you closed down the other vents then. My idea I think would have less flexability probably. Also its pritty costly for toughned glass which you probably dont need. I will be getting an 8 x 6 as well.
-
Just had a quick look at the trolley shelters on net they are £2500 so yes a little expensive and may not be that flexable for various needs a greenhouse could give probably. Anyway I shall await the answers for the shading in summer over Mesh to the wood connected to aliminium frame. Hope I am not imposing to much. It seems everyone is enjoying answering and I am of course very greatful.
-
£2500 ?? :o good grief, you can buy several off the peg aluminium houses for that money!
-
I like the look of some of the bus shelters we see around here (and we know that they are well ventilated!) but I gues that they would be even more expensive.
-
No David that is a fantastic answer thanks! On a cold or mild summer day it would still give good ventilation if you closed down the other vents then. My idea I think would have less flexability probably. Also its pritty costly for toughned glass which you probably dont need. I will be getting an 8 x 6 as well.
David, just to give you an idea in my 8x6 with non-toughened glass in autumn/winter/early spring I have:-
one pane removed from each of the door and end elevations both openings covered with good grade plastic mesh.
one louvre vent kit in each side elevation always open at maximum.
two roof vents, one each side, on automatic openers set to be closed (as far as these can be set!) only when it is really frosty (it's just a question of trial and error to get them right).
From late Spring and through what passes for summer here, in addition to the above I have
the door open all the time with a home made mesh screen as an inner door.
an additional pane removed from the end elevation
and an additional pane removed from each of the side elevations.
Being a devout exponent of the "Heath Robinson" style of DIY I have had numerous attempts at making frames to hold mesh to replace panes. None of them have existed for more than a few days without collapsing and thus causing much mirth to my other half :P
-
I use clear silicone sealer to repair any broken glass. Perhaps you could use this to glue mesh onto the inside of the openings, you would have to allow for the glass to be replaced.
Susan
-
Good idea Susan, Heath Robinson didn't tell me that! ;D
-
David, if you want greater coverage, whether against bugs orsun or wind, than the weldmesh provides, then it is simple to "sew" wind mesh over the rigid frame of the weldmesh ...... seeemples.... as the TV aristocratic meerkat says!!
-
Why don't I have all these ideas ??? Thanks Maggi.
-
Why don't I have all these ideas ??? Thanks Maggi.
bless you, David, it is the lack of good Scots blood, I fear!! ;D ;)
-
I remove one row of glass above bench high both sides of the greenhouse with my Disa in it comes out in late March and I put it back the end of October.
Derek
-
David, I took four lengths of wood, about 1/2" square, and made a simple frame the size of a glass pane. I covered this with the wind mesh that Maggie just mentioned then nailed similar width wooden lathes over the mesh and into the frame. The lathes overlap the joints in the frame making it quite sturdy. I then used horticultural wire to 'tie' the frames to the aluminium support. These frames have formed the back wall of our new greenhouse permanently for three years without any maintenance at all.
-
David S, many thanks for that, very useful indeed.
-
What an intersting topic this is. One day when I buy a glasshouse..... My mesh tunnel has good ventilation but is too dark now with nearby trees keeping the light out.
-
Thanks everyone! you have all been very helpful. I think I will use the mesh idea with medium sized screws. I'd screwed right in so the heads should hold the mesh to the the aliminium frames. Would this hold okay or should wood be used to hold the mesh as discussed.
-
David, we use the same clips to hold the mesh that would be used to holdthe glass into the aluminium frame, no problem with that and allows easy change from mesh to glass when wanted.
-
I think I have an idea which may suit some. What about if you drill about 8 small holes thread sturdy green thickish garden wire through them and wrap the wire around the mesh also so its held tight to the frame. The wire cannot slip down if done correctly and shading or other materials can then be tied with raffia to the mesh tightly. Does this sound okay?
-
Oh ,okay Maggie does that mean the mesh has to be the same thickness as the glass-are you talking about the spring clips or the other slotted clip. thanks
-
Well, I suppose the weld mesh we use is around the same gauge as the glass. It is the spring clips... the elongated W shapes, that we use.
-
Hi sorry to be a pain but I was wondering what make of mesh as some can be to flimsy from B&Q etc. Or will the spring clip adjust to a thinner kind as long as its rigid and not flimsy. Here's a link to show I am doing some of the work here. This is from b&q- http://www.diy.com/diy/jsp/bq/nav.jsp?action=detail&fh_secondid=9436441&ecamp=trf-005&CAWELAID=266985194 (http://www.diy.com/diy/jsp/bq/nav.jsp?action=detail&fh_secondid=9436441&ecamp=trf-005&CAWELAID=266985194)
Just to add ,the link picture above can be zoomed in on up close as it has a zoom tab below the picture.
This is diagonal mesh but may not be suitable as the clips may need to go over the mesh to then hold it from pulling out rather than on top of the mesh to hold it pressed down. If so it would need to be straight squares and 2 cm's like you said before. Is it this stuff-http://www.stainless-uk.co.uk/product.asp?id=7 (http://www.stainless-uk.co.uk/product.asp?id=7) or the green coating of plastic would probably look better over this steel.
Thinking about it the spring clip would only go through just over an inch gap not a 2cm gap so I think the mesh would be trapped down like the glass. Is it mesh that is not bendable thus sturdy for good frame work if I am right? You said sturdy above which means not bendable I assume.
Thanks.
-
Yes, the galvanised weldmesh we use is of a similar gauge and construction to the steel type in your second link.
It is not bendy at all, very rigid and the wire clips hold it well in place. I would think that would be the case with either of the two types you show. The first one from B&Q looks to be more of a sort that might bend a bit, but if it is sold in sheets, which it seems to be, then it may stronger than it looks!
-
http://www.allshelters.co.uk/index.php?webpage=smoking-shelters (http://www.allshelters.co.uk/index.php?webpage=smoking-shelters)
-
Okay Maggie I shall get the 2cm stuff rather than the 1 inch stuff so the spring clips can go over it and hold it down. At least I know its got to be good stuff. If B&Q do not have it did you get yours in a garden centre. If you bought it online and you can easily remember can you let me know. If anyone else reads this also it may be handy to know. Its not a big problem though as I can sought it myself obviously.
Thanks Dave
-
David, ours all recycled material from scrap. :D Waste not, want not!
-
I find it hard to imagine you could grow alpines in a glass greenhouse without removing some glass. My greenhouse is for cacti and it still gets too hot. It is relatively well supplied with vents compared to some, but even with a fan and the door open I remove a row of panes when it is sunny and warm. They go back in when it isn't so sunny and certainly for winter. You might want to consider only removing glass down to a certain height to discourage cats or rats from wandering in. Keeping birds out is harder, but you can put mesh on openings if necessary.
You might want to examine any potential greenhouse purchase for build quality. The cheaper ones are pretty flimsy and I wouldn't want to vouch for them in the wind with glass sections missing. Of course relying on the glass for rigidity is asking for trouble anyway. A fully closed greenhouse is OK in the wind, but if one panel or vent blows then another one will go almost instantly because the wind gets trapped. With enough panes missing this might not be a problem.
Toughened glass is nice when its in and properly fastened down, but it tends to come in large heavy sheets and the edges are vulnerable to chipping. Given the cost that might not be ideal for putting in and out regularly.
-
Ian, our grenhouses are the cheapest possible from B&Q and I remove glass every year. I am not going to comment on any effect in strong winds because that would just be tempting fate! :-X