Greenhouse advice sought from SoCal, Southwestern folks - Page 4 - Orchid Board

Ray · #31 01-11-2018, 06:47 PM

Another vote for height, but for a different set of reasons.

The lower the surface-to-volume ratio, the more stable the interior environment will be, year round. A cube is better than an elongated structure, but not as good as a geodesic dome.

With added height, you get significant differences in light levels, based upon the distance from the glazing, as the glazing is the "source" of the light, and inverse-square still holds true (although the size of the "light" is huge).

Concerning the slab, that really shouldn't be much of an issue. A decent carbide-tipped drill bit to make holes, and expanding anchor bolts to attach the base to the slab is really all you'll need.

Orchidbyte · #32 01-11-2018, 07:05 PM

I would use cinder blocks as base, build wall 3 to 5 high, fill holes with concreate, you might want to add some rebar, drill holes in slab and insert rebar, make sure you chip some of the cinder blocks to put a 2" or larger PVC pipe so you have drainage out. Paint wall with a waterproof paint, Put GH on that wall and there you go. I do know a great mason that is inexpensive if you need, also know electric and plumber guys as well, since I'm a landscaper, it all comes with the trade.

It will cost you more to build your own GH then to get a kit, the headaches with building from scratch are numerous. At least with a kit you get a warranty. Make sure you can get electrical and plumbing out there easy enough, make sure Electric is on its on circuit, since it will have to run fans, heaters and a swamp cooler or 2 depending on size of GH.

If you need any help I'm only a stones throw away.

darby · #33 01-11-2018, 09:48 PM

Excellent, thanks. I have an electrician and plumber but they're not always available, so I may have to ask for your guys.

Yeah, a kit probably makes the most sense. I like the idea of building from scratch but the chances of screwing it up up seem high.

Ray · #34 01-12-2018, 09:46 AM

My last greenhouse (#5) was the only kit I've ever had. It looked nicer than the others, which were all made from pressure-treated lumber, by the way, but frankly, there's very little to "screw up", if you're reasonably handy with tools.

darby · #35 01-12-2018, 01:21 PM

Hmmm. I'd say I'm reasonably handy, yes (I managed to build an 8x10' shed from a kit that's still standing) but I've heard more than one person say, like orchidbyte, that building from scratch would cost more in the long run than just going with a kit. What's your take on that?

I looked through the Roger Marshall "How To Build Your Own Greenhouse" book and it suggested using pressure-treated lumber coated with (I think) marine-grade epoxy and paint as an alternative to cedar/redwood--did you do something like that?

Roberta · #36 01-12-2018, 01:48 PM

A consideration on DIY in southern California - termites. Pressure-treated wood is quite resistant, redwood pretty good, cedar not so good. Since we don't have hard frost, termites have a field day. (Essentially all houses need fumigation after 20 years or so, greenhouses are warm and wet and have issues sooner).

darby · #37 01-12-2018, 02:04 PM

Good point...

Ray · #38 01-12-2018, 02:05 PM

Quote:

Originally Posted by darby

Hmmm. I'd say I'm reasonably handy, yes (I managed to build an 8x10' shed from a kit that's still standing) but I've heard more than one person say, like orchidbyte, that building from scratch would cost more in the long run than just going with a kit. What's your take on that?

I looked through the Roger Marshall "How To Build Your Own Greenhouse" book and it suggested using pressure-treated lumber coated with (I think) marine-grade epoxy and paint as an alternative to cedar/redwood--did you do something like that?

Do-it-yourself has always been less-expensive for me. I'm not sure what might make it more, longer term. However, the Turner Greenhouse kit looked a great deal better than anything I constructed. Maybe if I had been concerned about covering up glazing joints and the like, it would have added up, but I was more concerned about function than appearance early on.

My use of lumber was always unpainted, treated lumber, I even used it for tiered benches, and it never hurt any of the plants. In fact, I ended up replacing the wooden benches with polymer ones, because the roots didn't "grab" the plastic as well, making them easier to separate without damage.

dounoharm · #39 01-12-2018, 02:58 PM

a commercial cut flower operation I worked for in California used a copper based 'paint on' treatment every couple years...I think that is no longer available (anything that really works gets changed, lol)....also, most of the houses there were up on a 'knee wall' of cement block....

I built a knee wall here in texas also, because I love to use cedar....the legs of my benches are treated, but the top is cedar....

its very satisfying to be able to say, 'we built it ourselves'....and I always have at least one 'mistake' bravely shown....lol...