The Accidental Smallholder Forum

Growing => Vegetables => Topic started by: Fleecewife on December 21, 2019, 06:17:44 pm

Title: Keder Houses
Post by: Fleecewife on December 21, 2019, 06:17:44 pm
I'm looking into Keder houses with a vague a idea of getting one in a couple of years time, depending on whether or not it seems worthwhile.
We currently have a 7m x 14m Northern Polytunnels tunnel on our very windy upland site.  We also have a 6'x8' greenhouse inside the tunnel, near one end, as glass outside has no chance of surviving flying debris or strong wind gusts.  Neither is heated so not much grows in them in the winter, just some brassicas, leeks and overwintering garden plants.  In the summer the tunnel is used as most people would use their open garden, and only potatoes, broad beans and peas and some brassicas live outside.

@Anke I remember you mentioned getting a Keder house.  Did that go ahead?  How have you found it, and do you think it was worth the investment?  What size did you get and is it large enough for your needs?

Does anyone else have one?  Any advice?  I am trying to get an idea of prices, but the adverts don't give any actual figures, which makes it impossible to get a true idea, and implies that they are horribly expensive  :thinking:
Title: Re: Keder Houses
Post by: pgkevet on December 21, 2019, 08:08:46 pm
No experience of the keder but my citrus house is glazed with twin-wall polycarbonate. Was expensive back when i bought it 20+yrs ago but if oen could pick up a decent secondhand greenhouse with no glass it'd be worth considering DIY glazing.
Title: Re: Keder Houses
Post by: Anke on December 21, 2019, 08:24:37 pm
I just love my Keder - best decision we made (btw our polytunnel is also still going strong, but is used mainly as a hay storage facility, and I grew squashes/pumpkins in it this year). Our Keder is 3mwide and 10m long (5 sections of 2m each), and even though it doesn't stay frost-free, I am growing a good amount of spinach, winter salads in it, also have still some carrots and parsnips in it. It has 3 roof openings and they are automatic, so not so much of a panic if I don't open it first thing in the morning... I am also doing no-dig in there successfully.

If you are at a loose end - why don't you come over and have a look at it some time?
Title: Re: Keder Houses
Post by: Fleecewife on December 22, 2019, 01:58:28 am
Thanks Anke - come the summer when the days are longer we might just do that.  It would be interesting to compare it with ours.
I eventually found some prices. Yours sounds a very useful size and wouldn't totally break the bank.  I will have to work on 'him indoors' for a few months before he would agree, so plenty of time for research.
How is it in the wind? Ads claim it's specially designed to resist wind, so it should be fine here I think, especially now we have thick hedgerows, as long as it lives up to the claims.  Does it get roasting in the summer, or do the vents deal with that efficiently?

@pgkevet It's the overall structure of the keder house I'm interested in.  We have twin-wall polycarbonate for our henhouse windows but they are not strong in the wind, and the basic greenhouse we have would be too flimsy outside here.  Initially I worried about the glass greenhouse in the tunnel, with having lots of grandchildren around who all loved digging 'Granny Traps' in the tunnel, but it's been fine and they're old enough now to be sensible.
Title: Re: Keder Houses
Post by: pgkevet on December 22, 2019, 07:15:57 am
I'm not sure about your comment re strength in wnd. That's down to the basic design/construction. My Citrus house has had odd panels blow off in very high winds - but easy to put back.. but that's cos they're only held on with simple spring clips. At least they don't shatter hitting the deck and they are large sheets. The structure itself is solid even when I had the original version using just ground anchors (lengths of downpipe buried in ground and filled with concrete holding the ally anchors). It wouldnlt take much effort to make up more robust ways of holding the sheets in place. Sadly simply bonding them isn't too bright 'cos of their expansion coefficient unless using smaller sheets (as in pane sizes) or thicker single wall stuff.
way back when i built a conservatory kit and the polycarb roof holding system on those is very robust but more expensive. The downside to any of the twinwall or keder bubbel polycarb is lack of through visibility. I much prefer woking in my glass house with good views out the sides. it's not claustrophobia just much more like being outdoors but without the weather and enjoying the scenery. Downside is 1-2 broken panes a year and poorer insulation.

To be fair I do like the look of some of those keder houses but any 'gardener' size greenhouse doesn't have enough height for proper sized folk  :eyelashes: so mine are all on dwarf walls and wider than necessary to get the extra ridge height. Sadly I've got to the stage of age/back pain when a larger house wouldnlt get used enough 'cos I liked the design of the bigger keder stuff.

A lot of years ago i did design my ideal greenhouse - essentially simple brick columns between standard off the peg 'cheapish' UPVC double glazed patio doors and a polycarb roof. DIY it wouldnlt have been too terribly expensive but thoe sorts of construction days have also passed me by.
Title: Re: Keder Houses
Post by: Anke on December 22, 2019, 08:15:57 am
We have the "Gardener's" version, unfortunately the commercial size ones were just out of our budget... but we put a row of sleepers in as foundation (we had to dig into the side of a slope to make sure it is totally level) and that has added a bit of height. I have also build raised beds, about 1ft high only, but I think these will increase with time...
Height is not a problem.
The only thing you have to be aware of is to build it with regard to the main wind direction, and if high winds are forecast during reasonably warm weather you can screw the roof vents shut. If you were unlucky and had damage to the polythene, you can replace individual 2m sections of it, or the front and end panel separately, so no total recovering required. Snow also slides off easier due to steeper roof angle.

It does get warm in summer, but with vents open plus window and door at each end it wasn't as stifling as my polytunnel gets.  I have three vents, you wouldn't want more. Also got strengthening bars across.
Definitely two person job to put it up though.
Title: Re: Keder Houses
Post by: Briggsy from Gower on December 22, 2019, 10:03:05 am
Hi Fleecewife,

Bit of a tangent but there are oriental green that cheerfully grow throughout the winter given a bit or protection.

Check out Real Seed Catalogue, I grow Komatsuma (I am eating leaves and sprouts now and I know the plants will put on a new spurt of growth by early feb to replace my havestings) and WaWa which have stems that swell up throughout feb to make frightening looking but tasty veg.

They can take a serious frost and still bounce back. I know this as we chose to replace our existing tunnel during the beast from the east a couple of years ago so indoors became outdoors for the duration and they thawed out absolutely fine.
Title: Re: Keder Houses
Post by: PhilW on December 23, 2019, 08:31:58 am
Hi Fleecewife,
We bought a Keder "garden" greenhouse about 8 years ago. We are in a fairly windy spot in North Lincolnshire have had winds of 60mph+ over the years and the Keder had been very good while others type locally have collapsed. You must make sure the side faces the prevailing wind as recommended by Keder, the steel structure is concreated in, although a friend of ours has just put his directly into the ground and he has not had any problems. I would also ensure the vents/windows are on the opposite side to the prevailing wind, not essential but it does help. No problems with ventilation as both ends can be opened as required (door & window). By the way it is 3mtrs wide and 6mtrs long and you can extend the length in 2mtr sections.