Greenhouse Buyer's Guide: How to Choose One

Most bad greenhouse purchases come from deciding these in the wrong sequence - usually starting with price, which forces every other decision afterwards. This is the order that leaves you with a structure you keep.

1. Width. Fixed for the life of the building. It decides whether you get benches on both sides of a usable aisle, and it cannot be changed later.
2. Length. The cheap dimension, and the one to spend spare budget on. Adding length does not add doors or end walls.
3. Glazing type and thickness. Decides your heating bill and your winter capability. Also unchangeable without re-glazing the whole structure.
4. Frame material and rating. Check the wind and snow figures against your own address, not against an average.
5. Site and base. Sun, drainage, access, and a level square foundation - all of it before the pallet arrives.
6. Ventilation plan. Cheap to design in, expensive to retrofit after glazing.
7. Everything else. Benching, heating, irrigation, automation. All of it can be added next season out of ordinary spending.

Specification pages in this category are unusually vague, and the vagueness is rarely accidental. Here is what a complete one contains and what each line is hiding when it is missing.

Two numbers decide whether a greenhouse survives where you actually live, and both are published for your address by your county building department: the ground snow load and the design wind speed used for permits in your area. Look them up before you shop, then buy against them rather than guessing.

Be careful with how ratings are presented. A range of models rarely performs identically, so a single figure quoted across a whole catalog is usually the best model's number applied to all of them. We state ours per series because they genuinely differ: 75 mph on the Arc Series, 65 mph on the Loft Series, 65 mph on the Gable Series, with 5 ft of snow shed across all three. Averaging those would flatter two of them and mislead you.

And remember what a rating assumes. It describes a frame properly anchored to a properly built base. Unanchored, none of the numbers mean anything.

A greenhouse does not arrive by parcel courier. It arrives on a pallet, on an LTL freight truck, and the process works differently in ways that matter:

• The carrier calls to arrange an appointment. You need to be there.
• Delivery is curbside, not to your chosen spot. Getting several hundred pounds of pallet from the roadside onto your property is your responsibility, and it is worth arranging help in advance.
• You must inspect the shipment before signing. A clean signature on the delivery receipt is the carrier's evidence that everything arrived undamaged, and it makes a later claim much harder. Note any damage on the receipt before you sign.
• There is a damage-claim window. Photograph the pallet before and after unwrapping.

Compare delivered prices, not sticker prices. Freight on a unit this size is real money, and a low headline with freight added at the final step is the most common way a greenhouse ends up costing more than you planned. Our prices include curbside freight to the lower 48 states; Alaska, Hawaii, US territories and PO boxes are quoted separately. We do not promise a transit time, because the LTL carrier is not ours to promise for.

• Rounded dimensions with no exact figure anywhere. If the listing says 10x20 and the spec table does not say what it actually measures, assume it is not 20 ft.
• One wind rating quoted across an entire catalog. Different shapes and spans do not perform identically.
• A strikethrough price with no real reference behind it. A permanent "sale" against an invented list price is not a discount. Where a genuine reference price does not exist, the honest thing is to show no strikethrough at all.
• Reviews that do not belong to the seller. Imported, purchased or generated reviews are worthless and, in the US, misrepresenting them breaches FTC rules.
• Ticking clocks and stock counters on a made-to-order freight product. They are theatre.
• Monthly payment figures quoted in the headline. A specific monthly number is a credit advertisement and the real figure depends on the term you are approved for.
• No published parts list. You should know what is in the box before it arrives.
• Polycarbonate with no mention of UV protection. Unprotected sheet yellows and embrittles quickly.

1. What are the exact external dimensions and the peak height?
2. What is the wind rating for this specific model, and what snow load or shed depth?
3. What thickness is the glazing, and is it UV-protected on the exterior face?
4. What is the frame section size, and is it hot-dip galvanized or coated some other way?
5. What exactly does the warranty cover, and for how long?
6. What is included in the box, and what will I need to buy separately?
7. Is freight included, is delivery curbside, and which states are covered?
8. What happens if parts are missing or damaged on arrival, and who files the claim?
9. What is the return policy, and who pays return freight?

Since we just told you to ask, here are ours in the same order.

• Dimensions are stated exactly on every listing and spec table. Our lengths are metric conversions - 6.5 ft, 13 ft, 19.5 ft and up - and we publish them that way. A 10 ft x 19.5 ft unit is never listed as a 10x20.
• Ratings are per series: 75 mph wind on the Arc, 65 mph on the Loft, 65 mph on the Gable, with 5 ft of snow shed across all three.
• Glazing is UV-protected twinwall polycarbonate in 4 mm or 6 mm.
• Frame is 1 in. square hot-dip galvanized steel tube.
• Warranty is a 3-year frame warranty.
• Included: frame, glazing, both Dutch doors, hardware and the assembly manual. Not included: base materials, ground anchors, benching, heating and ventilation accessories.
• Freight is included, curbside, to the lower 48. Alaska, Hawaii, territories and PO boxes are quoted separately. We do not promise a transit time.
• Returns require unopened, original condition with undamaged polycarbonate, and the customer pays return freight.