buying a greenhouse

We're thinking of taking the plunge and buying a greenhouse. The first stage in this was to visit a garden centre, decide that 6'x8' is probably the right size, and have tea and cake in the cafe!! Having done that, and started to research the subject on the internet, I've realised that there are quite a few decisions to make, and would be very interested to know what experience other people have. We're in the fortunate position of being able to buy a new one, but we need to think about what kind of base to put it on (it'll be on the bit of ground we used to call the lawn!), and whether to have safety glass or polycarbonate. The hens free-range around the area (and it'll be lovely for them to have a place to sit inside in the winter!) so safety for them is an issue, as they will peck up anything which looks interesting including glass.

Dandelion, how exciting!

Many people say that they wish they'd got a bigger greenhouse though personally I find my 8ft x 6ft is adequate. Mind you I'm not an avid greenhouse user.

I would say it needs to be glass, polycarbonate does not let through enough light. I didn't know you could get safety glass for GHs, must be pretty pricey.

I have fixed some lightweight plastic fencing around the outside of mine to discourage any creatures from thinking of breaking in. Once, in the early days, I had my quail in there while I was sorting out their accommodation and my dogs broke in through the glass and killed them  

Mine is sitting on bricks set into a little concrete but only at the corners and a couple of places along the sides. The floor is packed earth but I put a plastic membrane down and biggish gravel on top of that. Handy when you want to damp down on hot days.

The only other comment I have at the moment is make sure you get good ventilation. A through-draught is very worthwhile as are automatic openers. Already this year mine has got up to 35*C on a warm day and that's with a louvre vent open and a window in the roof. It goes to 40 in the summer even with some shading.

You've obviously already decided on your site. I inherited a greenhouse with the house and it is a lean to on a shed (I can enter it from the shed). The great advantage of a lean to is that you have te full height of the apex where it is against the wall - in fact, I've got netting on the wall so can grow things up it to about 8'.
Would agree with Flo about the glass - polycarbonate gets very discoloured after a couple of years and must cut down the light considerably.
Would also agree about the ventilation - it's often advisable to get additional louvres and / or roof vents to those included in the package. I think another optional extra to consider is guttering for rainwater collection.

My gh is 8' x 14' and it gets pretty full because there are so many things I can't grow outside. It has a concrete floor which I wouldn't recommend. It's cracked and subsiding now & I get plagues of ants coming up through the cracks and rat runs underneath. It is my intention to replace the gh when it finally gives way and I was thinking about putting a couple of good raised beds in with gravel & weedproofing in between. I thought that raised beds would be easier to empty occasionally to keep disease at bay than to plant directly in to the ground.

I think I agree with everything said already !

I have a building called "The Retreat" in catalogues. My father bought it for me when I got married - can't think why . Anyway, it combines a 6x8' greenhouse with a 4x8' shed. It is cedar, which is my preferene because it has much better resistance to rot than most other wood. Because we were anticipating a family, and it is near to a big apple tree that drops fruit all over, I went for toughened glass. I would definitely do the same again; not only has nothing ever broken, but because it is toughened big sheets of glass can be used, so fewer glazing bars and no lap joins full of algae. The result is a nicer looking building that lets in lots of light.

The things I would change are the base and height; it is straight onto a paved patio area, and I have considered excavating beds below the patio level to get height for more trusses of tomatoes - sunken beds ?

That is SO helpful! Thank you everyone. We had a little pootle out to the garden centre in Tewkesbury, which although small does have a good selection of greenhouses to look around. I think going round a few turned my mind from polycarbonate to glass: the greenhouse will be in front of the kitchen window, and I would rather look through it than at something opaque. We went into a lovely little wooden one (probably cedar by the smell) and it was much better than the others. Still at the planning stage, but I've got a lot more to go on now.

Will look forward to hearing more of your thoughts and, ultimately, the result of your deliberations, Dandelion.
The dandelions are starting to appear in the garden now - they are such delightful flowers.

I'm so glad you like dandelions Flobear, they are a high quality forage plant for bees when there's not much else around. I like to see people's expressions when I do bee talks for gardening clubs and tell them that if they want to help bees they should leave the dandelions.

Gosh they must love my lawn then

I used to leave the dandelions to grow when we had guinea pigs - it saved a lot of money, not having to buy them greens!!

Well, this is it. Finally it's finished, but fairly empty, because I don't want to rush into buying staging before I know what I really need.

Looks good D. I didn't realise that you aren't restricted to 2' square panes of glass, as you are with the cheap horticultural glass. It makes for a really clean looking greenhouse and it will be so much easier to keep clean as well.

There's posh Dandelion. I'm sure it won't look empty for very long. Is that a chicken I spy looking longingly at your plants? It hadn't occurred to me either about the long panes. My gh always has grotty green bits where the panes of glass overlap

It's lovely and clean at the moment - we've made a path down the middle through the gravel with (don't laugh) carpet tiles. We tried some decking squares, but they were just too high as I trip up easily. The carpet tiles were sitting there not doing anything so we thought we'd try them out. I know they'll get messy in the winter, but they'll brush clean. I am NOT taking the hoover into the greenhouse...

It does indeed look smart. That you can have large single sheets with toughened glass is good enough reason to go that way IMHO. I know it is a coal tar derived not so green product, but I have been using a few drops of Jeyes fluid to the water when I wash the outside of the greenhouse and conservatory. I'm still using the same can that was in the garage when we moved in here about 15 years ago ... it seems to delay the return of algae by quite a long time.

The carpet tiles might be good for a while, but will surely go mouldy eventually ? There are some sorts of rubber matting that might serve, if it doesn't get too slippy.

Thanks for the Jeyes fluid tip CH - the smell reminds me of working in a small rural garden centre on Saturdays when I was at school!
I'm going to keep my eyes open for a pathway alternative - Mr D gets very worried about me falling over, so this was an interim solution. I've just received my Amazon order of the Hessayon book on greenhouses, and one by Alan Titchmarsh. They complement each other (yes, that's my excuse for buying two books instead of one...) and seem to have some very practical ideas and suggestions.

I was catching up with Gardeners World on the iPlayer this evening. I watched the one filmed at the Malvern Show - and what had been used in one of the show gardens, but carpet tiles for some of the path! Great minds and all that....!

freebird wrote:I was catching up with Gardeners World on the iPlayer this evening. I watched the one filmed at the Malvern Show - and what had been used in one of the show gardens, but carpet tiles for some of the path! Great minds and all that....!

Sorry - I missed this.
Well - what can I say? We're only a short distance from Malvern: carpet tiles in the garden is obviously a regional thing!!

We have had to contact the greenhouse firm, as the door didn't actually shut properly. I photographed the strip of sky which could be seen when looking at the closed door from the inside, and emailed the firm. We have now had The Man round, who replaced the strips of brush-like insulation material round the door, but still isn't happy about the fit. I think The Other Man will be visiting next week to have a look, probably to put some extra bracing pieces in the push the door frame out. It must be a teething problem with the design: he had already done the same job for several other people.