Comments on: Greenhouse or Polytunnel?

By: leen

leen — Fri, 24 Apr 2009 16:27:17 +0000

so it is this polycarbonate gleasing thing .

By: leen

leen — Fri, 24 Apr 2009 16:24:49 +0000

Joaõ in Chão sobral mead a nice one with this material that they juse for roofs,it is long lasting ant rains clean but is expensive .Maby he can tel us the name

By: andy

andy — Fri, 17 Apr 2009 15:55:43 +0000

update: the weather has cooled, so we went to town to get some black plastic pipe to build a poly tunnel – using old scaffolding as the bottom walls/supports.
polycarbonate 6m lengths are less than 5 euros each, and will last longer than the ‘water pipes’ i intended to use.
the solar resistant plastic cost us 35 euros for 8m by 8m.

so a small home-made polytunnel is going to cost about 50 euros, compared to almost 2000 for a greenhouse! will post some photos as soon as the pipe is delivered and we get it up.

By: sophie

sophie — Thu, 16 Apr 2009 09:29:23 +0000

thanks everyone for your comments, keep ‘em coming!

at the moment i’m leaning toward the polytunnel (to be truthful i was from the beginning, if only because the ‘real’ ones are just too suburban garden for me!).

derek – i can get sail material but it’s VERY expensive. the plastic they sell in the agricultural co-op is designed for polytunnels so it’s reasonably long-lasting and cheap.

dylan – thanks for the comment. just visited your blog – looks very interesting, i will have a proper read later! also will read the Solar greenhouse resource linked from your blog which looks useful http://agebb.missouri.edu/mac/library/linkview.asp?linknum=4316

if anyone’s interested in more comments, there’s also a discussion going on over at facebook http://www.facebook.com/home.php?#/posted.php?id=536527081&share_id=69823432454&ref=mf#s69823432454

By: dylan

dylan — Thu, 16 Apr 2009 08:14:16 +0000

HI i’ve had good success with the homemade blue pipe tunnel, if you want to use less plastic face it south and use wood for the northside, it doesnt get much light anyway..
plastic obviously degrades and won’t break down in the environment for a couple of hundred years- it just gets smaller and smaller. so glass is probably a better ooption. There’s a lot of embodied energy and environmental damage in aluminium…
tough choice..

By: Derek

Derek — Wed, 15 Apr 2009 22:20:27 +0000

As a current glass green house owner i can tell you we have only had to replace 3 “panes” in the three years we’ve had it. You do have to wash it to keep that nice transparent effect,…sans the green mildew, but also ive noticed that our aluminum frame is oxidizing at structurally vital points, and wonder if this will be a problem in 2-3 years. Our green house is on a wood frame, which is rotting and will need to be replaced maybe next year, and every winter we get one serious hail storm, and one snow dump (here in the armpit side of Denmark), that tests the roof panes.
We have thought about it and like the idea of being able to ‘break-down’ the poly tunnel,…use bamboo for a structural material, and move/store it entirely to get it out of the summer sun, and to ‘cycle’ the underlying earth. Our vote is for the polytunnel.
Of course the concern for longevity of the ‘poly’ is noted, but why use polyethylene. Is it possible you could find a source of discarded transparent sail material or kite material (nylon, polyester, other?) the rest of the tunnel is so cheap maybe searching for a good long lived material that cost a bit more but would still provide that green house effect would be worth it.
Just an idea,
-d

By: Wendy, Aonghas & Oonagh

Wendy, Aonghas & Oonagh — Wed, 15 Apr 2009 15:02:15 +0000

As an ex-owner of 2 greenhouses who had to rebuild both (very carefully) from the ground up after a particularly violent Christmas storm where all we could do was sit indoors listening to the sound of breaking glass, I can certainly tell you that greenhouses are not necessarily likely to last any longer than polytunnels!!

Like the new look to the blog!

By: Nuno

Nuno — Tue, 14 Apr 2009 20:08:23 +0000

Olá Sophie,

I’ve been enjoying the blog for a while, congrats on the new look.

In Agrovida you can find some available greenhouses (by Rovero): http://agrovida.com/agrovida2.html

An advice someone gave me was to check out the local Grémio de Agricultores or Cooperativa Agricola for second hand sales, list is here:

http://www.confagri.pt/Associadas/Cooperativas/?wbc_purpose=basicdefaultdefaultdefadefaultd

Or maybe second hand sales on online ads like these:

http://bejacity.olx.pt/estufas-em-ferro-galvanizado-para-horticulas-iid-22384527

http://valedecambra.olx.pt/vendo-estufa-iid-18309425

Hope you can find something, cheers!

By: admin

admin — Mon, 13 Apr 2009 20:15:31 +0000

Well Gav has just thrown a spanner in the works with this:

“Go for polycarbonate whatever, most expensive but the only fire-resistant option – check out http://www.geodesic-greenhouse-kits.com/features.php for some ideas too – they have some great features in their greenhouses that could be translated to a self build xx”

Now … if I could get one of those in Portugal …