Replies

1. 
   Louis_Wilson | Mar 25, 2001 04:54am | #1

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   I've only built one greenhouse, did it a few years ago with pre-bent, pre-drilled galvanized metal tube. We site built the end walls out of treated lumber to fit the arched profile of the ends. This was basically a framework that a fairly tough plastic is stretched over to create the greenhouse. Problems with disassembly from what I saw is that the short vertical starter tubes are embedded in concrete. They might yank and they might not. Given the high moisture and fertilizer environment, seems like you might have some corrosion on fastners making them tough to take apart short of a Sawzall or grinder. If lots of time is your friend, I could see eventually getting it apart and rebuilt elsewhere. For your intended size, I would look in a commercial greenhouse supply catalog like "Stuppys" (spelling?) and check out kit prices. The stuff is modular, so you can work small if you need to. I would look real closely at an existing greenhouse prior to making any offer to buy. Really, I would probably be more inclined to tell them how much I will charge them for disassembly and removal from site. Treat it like a job, not a purchase. As to the gravel floor, that's how we did it per the specs supplied. One thing that comes to mind relative to the concrete slab is that plant watering will slop on the floor and then what? So you have a drain, but I bet you will still have puddles. I don't know about father-in-law's reasoning, he may be right. Gravel seems to work better for comfort, no puddles, and costs less by a margin. Seems like the soil under the gravel would become saturated and act like a rehydrator when humidity levels in the greenhouse drop. I am not a greenhouse expert at all. Most nurserys that I have been to seem to be constructed along these lines and I pay attention just out of interest. Hope this helps.

1. 
   david_seyfert | Mar 25, 2001 10:21pm | #2

   *Thanks for your input. Maybe I need to advertise myself as a "greenhouse removal specialists" as a way to find a used one and make a little money at the same time. I'm still not sure what the effects on the enclosed section of the house would be. Was your greenhouse free standing or attached? If attached, how has the house held up?

1. 
   Cal_Howard | Mar 26, 2001 02:06am | #3

   *David- I have a shed lean to that I built years ago. P.T. 4x4 frame in ground in filled w/p.t. 2x4 16 o.c.. P.T. ply buried in grade w/tar coating on exterior below grade and as sheathing ( matching sidewall and trim). Rafters are 2x6 cedar with drip cap flashing on top and 1/2" parting strip down center. Glass cut 1/4" less than space between parting strips and bent copper glass hooks with glazing laid on like shingles. Cedar strip over finished glazing / parting strip w/ stainless screws. Interior rigid insulation under shiplap walls. Floor crushed stone over sandy soil with a deck walk on sleepers removable to rake stones and water down spilled dirt. Dirt containment can be a big problem. Soon to build an open grate planting area with catch under. Hydrolic roof vent a must- Charlies Greenhouse supply (somewhere in the mid-west) had them. Lower vent to encourage air flow. Good luck it's all worth it. Cal

1. 
   Steve_Turner | Mar 26, 2001 03:04am | #4

   *David, for several years I sold and erected residential and light commercial greenhouses. I've built a bunch of 'em, and have one at my own home.First, don't use a slab. Pea gravel is what I generally used. Some pre-cast stepping stones might be desirable, but the basic gravel floor is just what you want. The excess moisture from watering will come to assist you in the form of humidity.All of the pre-fab greenhouses I'm familiar with set on a low masonry sill (glass-to-ground models), or on a masonry wall. Rot won't be a problem.Footings are critical... the foundation a green house sets upon must be level and stable. The slightest shift will result in broken glass and a virtually impossible job of reglazing.You CAN disassemble a quality aluminum greenhouse (i.e., Lord & Burnham), but you'll be without benefit of the drawings so helpful for reassembly.If you do decide to take down an existing unit, you will probably get it for free (or quite likely the owner will pay you to take it down).Most of a greenhouse assembly/disasembly is mechanical work (presuming we're talking about pre-fab greenhouses erected from aluminum extrusions and utilizing barcap glazing). You probably own all the tools you need except a suction cup, and the trick is to know the sequence of events as you take things apart and put them back together.A critical point: you must break away the mortar or other masonry to expose the sill anchors, and then cut them loose with a sawzall... don't try to detach the sill by prying it away: you'll end up destroying a critical and possibly irreplaceable extrusion.There's too much to share with you here right now... E-mail me if you find a used greenhouse you like, and I'll go into all this in detail and pass along some critical safety tips.Good luck, Steve

1. 
   Jeff_Clarke_ | Mar 27, 2001 03:06pm | #5

   *david - As a house addition, how would your local/state code address overhead non-tempered glass? I'll be that most of the "free" greenhouses have non-heat-treated overhead glazing.Just 2 cents.Jeff

2. 
   Jim_K_ | Mar 27, 2001 05:36pm | #6

   *I used a redwood/mahogany kit 15 years ago. Worked great. Tempered glass, double pane. It was really strange to be able to clear snows off by walking on the glass (slippery, but I was younger then, too). Heed the advice to good ventilation. We never put in good enough venting, and paid the price every summer, all summer. The redwood still looks great, though. An elegant alternative to aluminum.

3. 
   Pete_Draganic | Mar 27, 2001 05:40pm | #7

   *There seems to be a mjor point being missed here. If I understand this matter correctly, you wish to build a greenhouse attached to your home. If this is the case, you will undoubtedly be introducing massive amounts of moisture into your home which is a very bad idea. This greenhouse should be either seperate form the home or attached by a breezeway in an airlock fashion although I suggest a seperate structure as the breezeway will still intorduce amounts of moisture into your home that you do not want.Pete

4. 
   Cal_Howard | Mar 27, 2001 10:11pm | #8

   *Pete - Typically a door or slider is put in to separate the rooms. Heat is the big problem as spring and summer roll around. In the winter a little humidity is o.k. too but like any special use room, it takes a little while to figure how to drive the thing.For instance some plants don't need high humidity. It depends on how you are going to use it. Seed propagation relies on base watering and covers. Certain exotic house plants like African Violets want heat and humidity. Hanging flowering type generally like to be misted- then you've got humidity. So it all depends. In general we find ours to be too dry as the vents open in the winter to let out extra solar heat build up on a regular basis. One other thing- don't forget the shade system for the sun and in really cold climates or just too much heat loss at night, roll down insulated barriers made for greenhouses. cal

5. 
   Steve_Turner | Mar 28, 2001 03:51am | #9

   *Pete, I figured he wants to add what we call a "lean-to" greenhouse, which is essentially half of a free-standing model. The greenhouse in this instance would not be open to the home, but would be placed against an exterior wall. Generally, there is some type of door directly from the residence into the greenhouse, but this is not always the case. I'm also presuming he wants to use the greenhouse as a greenhouse, and not for some half-baked solar collector.Anyhow, I've built a number of lean-to models (maybe 25 or so) and have neve had a problem with moisture infiltration. Admittedly, I made certain the party wall was well caulked and painted, although many were against brick structures.When the greenhouse is open to the residence, it becomes a "solarium" and a whole new set of issues arise...Regards, Steve

6. 
   Steve_Turner | Mar 28, 2001 03:54am | #10

   *Walking on the glass itself? You gotta be kidding! I's sooner try to walk on water (or would at least expect more success).Amazedly, Steve

2. 
   seyfert | Mar 28, 2001 03:54am | #11

   *
   I'd like to add a glass greenhouse (around 10' X 10')to the back of our house for my wife. My father-in-law, who has had a few hobby greenhouses, recommends avoiding pouring a slab and using just crushed stone for a floor. He says that a slab inhibits moisture to too great a degree for a greenhouse and even with misters it's hard to create a wet environment for plants. I have two questions. Does anyone out there have experience with this type of project and do they agree with the slab/crushed stone advice? With such a moist environment, how do I protect the framing and siding from problems with wood rot and mold? By the way, I've seen classifieds for used greenhouses which are fairly inexpensive, the catch is you have to disassemble. Anyone ever try this? Is this just a case of unbolt and stack or is this a job better suited for torches and cutting tools. Thanks for the input.