I'm thinking about building a greenhouse in the front yard for next year's garden since planting on the side of the carport didn't work out so well this year.
Somewhere inside or around the staked in area because that's where I get the best light.
My thought going forward is to dig into the hill and make the floor level with the lowest spot, then framing it in.
Would I be better off with cedar or PT lumber since it's going to be up against the dirt?
I'm hoping to only have to build it once, but we do get a healthy amount of rain every year.
Cedar is rot resistant but will still rot, especially with ground contact. Pressure treated will eventually fail (ie, termites don't like it as food but they can eat through it to get to better wood.) but will last a lot longer. I would use "ground contact" rated pressure treated.
In reply to Dr. Hess :
But while pessure treated is good for contact with dirt, it is heavy, real heavy compared to Cedar and there is potential to leech toxic’s into the soil.
Dont fall in love with wood. Stone works well and It may not be significantly more expensive. Wood prices are very high compared to the past. Due to the import tariffs with Canada.
In reply to frenchyd :
Cinder blocks and paving stones are another option I've been considering. I haven't priced them out yet, but it's a hell of a lot more work than grabbing 6 2x12s and some studs.
I still haven't decided if in going to build panel style or hoop house style. Wood is much easier to attach everything for a panel, but blocks already have holes for a hoop house.
Modern PT doesn't have the issue of leeching toxins that old pt used to, just fyi.
In reply to RevRico :
How long do you plan on living there?
Useful life of wood is likely 5-7 years. Useful life of paving blocks and anything made from cement is 20 years or so.
Useful life of stone somewhat depends on the stone but 35 years for more sedimentary type to hundreds or even thousands of something like granite.
To be fair some of that life depends on things like earthquakes and other ground movement such as freeze thaw cycles. Plus the care you spend in stacking them
The. thing I like about stone is often you can find it free or near free. A neighbor “ rescued” granite paving stones and used them to line his driveway. It gave his driveway a real British flavor.
Decades later a developer shoved them in a pile and I missed getting them for free by 1 day.
I would have used them as edging around my bricks in the driveway. Those bricks date back to 1903 ( and I got about 30,000 delivered free for a case of beer)
The Granite paving stone came from St Paul and predated the civil War. Rimmed around the reddish bricks with Gray stone would have been such a rich look.
bluej said:
Modern PT doesn't have the issue of leeching toxins that old pt used to, just fyi.
Anything that is used to prevent wood from rotting is not something we should treat lightly. Use gloves etc.
Plus even pressure treated in constant contact with water and dirt will eventually decay.
I’m not saying don’t use pressure treated. Just realize that it too has limitations.
We build basements out of pressure treated lumber around here, and with all the sulfites (?) in the soil around here, they last about as long as a concrete basement. I would probably go with wood, and research what they use for treatment/sealer on the outside for basements.
frenchyd said:
Useful life of wood is likely 5-7 years. Useful life of paving blocks and anything made from cement is 20 years or so.
20 years for cement? You are aware that house foundations are in ground contact and made from concrete. 100 year old concrete blocks are not uncommon. My first house was built in 1928 and the foundation concrete blocks looked like new.
Wood is also going to last way longer than 5-7 years. I have a redwood play set I just got for free and, despite being totally untreated, it held up for 15 years or so before the insect damage got to be too much. I've cut out and replaced parts with pressure treated. It's a copper compound - the toxicity is no worse than copper pipes. I expect the wood to outlast the usefulness of the play set to me, which is probably about 10-12 years given my youngest is 2. Treated wood can be expected to last 40 years in ground contact installations if done right (good drainage, no pooling, insect infestations kept under control).
He wants to build a garden greenhouse and you're seriously recommending granite for the foundation?
He wants to build a garden greenhouse and you're seriously recommending granite for the foundation?
Yea, were talking a "structure" that's gonna be like 30 sticks of 1" pvc and some 6 mil plastic. Probably gonna spring for another roll of 1/4" hardware cloth to pretend I'm snake proofing the floor.
I've built these before above ground, but taking the hill slope into account messes with my math and makes all the plants sit angled to fall down, so I'm burying the base, 12-15" at the deepest along the side closest to the house. Probably a little mow secure from the wind dug in too.
I am jealous of people that live close to big cities for the sole reason everything free and useful on Craigslist isn't 3 hours and a tank of gas round trip for them.
Ill ask about ground contact PT when I'm at the lumber yard next. Maybe I'll get an extra yard of gravel when I redo the driveway to put around the perimeter too.
dculberson said:
frenchyd said:
Useful life of wood is likely 5-7 years. Useful life of paving blocks and anything made from cement is 20 years or so.
20 years for cement? You are aware that house foundations are in ground contact and made from concrete. 100 year old concrete blocks are not uncommon. My first house was built in 1928 and the foundation concrete blocks looked like new.
Wood is also going to last way longer than 5-7 years. I have a redwood play set I just got for free and, despite being totally untreated, it held up for 15 years or so before the insect damage got to be too much. I've cut out and replaced parts with pressure treated. It's a copper compound - the toxicity is no worse than copper pipes. I expect the wood to outlast the usefulness of the play set to me, which is probably about 10-12 years given my youngest is 2. Treated wood can be expected to last 40 years in ground contact installations if done right (good drainage, no pooling, insect infestations kept under control).
He wants to build a garden greenhouse and you're seriously recommending granite for the foundation?
And a British V12 to run the irrigation pump.
In reply to RevRico :
Whatever the material use a waterproof membrane or coating on the exterior of the high side. Otherwise you will have ceaseless water issues inside and accelerated degradation of material.
In reply to dculberson :
It depends more on weather conditions than anything. Sitting in the dry desert wood, ordinary wood lasts a very long time. But here in the frozen north freeze thaw cycles play havoc with concrete sitting on ground.
I mention granite not just because of its durability but because it’s cheap and plentiful. Plus I love the variety of colors.
Perhaps you don’t know how to find worthwhile things cheap or free. I’ll admit that you can pay a lot for something but it’s also relatively easy to get stuff cheap or free. Next time you see a house/ building torn down, look at what goes into the dumpster. Visit a swap meet on the afternoon of the last day. Look in peoples back yards, behind the garage. Join social clubs and mention your intersts. I’ve given away plenty, when I was actively racing Jaguars, club members would come to me for free interiors HVAC. Stock wheels and tires. In turn I’d be offered free or near free whole cars just so the owner could get rid of it.
bluej said:
Modern PT doesn't have the issue of leeching toxins that old pt used to, just fyi.
There are working two creosote plants that I know of in this state. I wouldn’t want to grow vegetables around that.
Yes I do know some pressure treated isn’t as nasty as all that. Plus it’s possible the OP won’t grow food. But use it as a landscaping technique.
I just tore down a fence and a playhouse made of PT lumber. They were rotting badly and since they do not pressure treat quality grades of wood they were also split, twisted, warped and generall unsightly. I would go with good quality straight grain cedar. Even if it doesn't last a lifetime it will always look much better than cheap SPF pressure treated.
By the way the treatment now is a salt solution so you need to be sure to use the correct hardware. Regular deck screws will rot away in a matter of months.
bearmtnmartin said:
I just tore down a fence and a playhouse made of PT lumber. They were rotting badly and since they do not pressure treat quality grades of wood they were also split, twisted, warped and generall unsightly. I would go with good quality straight grain cedar. Even if it doesn't last a lifetime it will always look much better than cheap SPF pressure treated.
By the way the treatment now is a salt solution so you need to be sure to use the correct hardware. Regular deck screws will rot away in a matter of months.
You are right about the quality of pressure treated wood. To a degree!
Most high grade knot free woods command such a premium that they are sorted out and used for furniture and other special applications.
However occasionally smaller independent sawmills simply need to produce a large quantity of wood as fast as possible. That’s called mill run.
Mill run is the cheapest grade of wood and it’s also the best and worst grade. Because they don’t take time to sort wood nor have a grader grade the wood it is the least expensive wood.
Pressure treated can be graded or not.
I built a cedar gate and mounted it on a cedar 4x4 support post in my back yard 30 years ago. The post was just set in the ground, no concrete.
The post finally rotted and tipped over at the beginning of May. Considering how long it lasted, I guess I can't complain too much about it.
In reply to frenchyd :
Creosote and modern copper treated wood is not in any way comparable.
Decades of hunting around for scrap material is not practical if someone wants to build a greenhouse now.
dculberson said:
In reply to frenchyd :
Creosote and modern copper treated wood is not in any way comparable.
Decades of hunting around for scrap material is not practical if someone wants to build a greenhouse now.
+1 on the pressure treated.
Also concrete lasts a very long time 20 years is absurdly low figure. I mean....Hoover Dam was built in 1931. Seems to be working well....
In reply to dculberson :
With regard concrete, reportedly there is part of a Roman road done in concrete that’s over 2 thousand years old. Yet concrete paving bricks around here have started crumbling in as little as 7 years. I suspect freeze thaw cycles, how it was made, and other factors affect life.
Someone here claimed pressure treated is cooper while someone else said salt. The city of Mound used creosote treated on the wood retaining walls they erected.
It seems like maybe there could be a variety of treatments?
As far as hunting for decades? I got the bricks for my driveway the first summer I lived here. I found the good deal on timbers once I got my building permit. Within a month or so. Maybe I have a good eye for opportunities?
Now yes it took me decades to build my house, in fact I’m still working on it. I’m hoping to be finished by the time they start digging my grave.
How long does it need to last? I'd probably do a single layer of block for ground contact then some cedar. When it rots out in 30 years replace it.
Or look on CL for scrap wood and use literally whatever is available (on top of block or pavers)
In reply to ProDarwin :
Yes you can go cheap as in not costing a lot but looking nice.
Or you can go cheap as in not costing a lot and looking cheap.
The funny thing is, some people just don’t care and think they can’t have nice. While others are more creative.
only so much lipstick you can put on a structure like this. It's going to look cheap because it is, and I am firmly, heavily rooted in the function over form camp.
I do have time to search for deals, but when the whole project buying new comes in under $200 and less than 20 minutes round trip, I won't waste a day and a tank of gas trying to save a few bucks
I'll be happy if it lasts a season. If it lasts longer, awesome, if not, learn from my mistakes with a rebuild. I don't expect anything but the base to survive over the winter.
Now, if you've got a good way of moving all the dirt I need to move without spending a grand to rent a machine for a day or all summer with a shovel, I'm all ears. There are a bunch of machines in the neighborhood already, but I don't really know any of their owners, maybe a sign and some BBQ will help foster a trade.
