How we judge greenhouses, brands, glazing, and product claims

What goes into a guide

We use manufacturer documentation, published specifications, engineering specs and wind and snow-load standards (ASCE 7 and local ground-snow-load references), horticultural sources, and a large amount of buyer-friction analysis: what breaks budgets, what fails in the first winter, and what owners regret after the first hot July.

The specs we verify on every glass greenhouse: glazing type (tempered, horticultural, or float glass) and light transmission, frame material and section strength, whether the base and anchoring are included or extra, the rated wind and snow load, ventilation (vent area as a share of floor area, and whether automatic openers are included), warranty length and what it actually covers, and realistic assembly labor. On every polycarbonate or kit greenhouse: wall count and thickness of the glazing (single, twin, or triple-wall), UV coating and expected yellowing life, frame gauge and how it anchors, whether it ships with any vents at all, snow and wind rating, and the real assembly difficulty behind the “easy setup” claim.

And on every recommendation, the all-in range, not just the kit price. A kit price without the base and anchoring next to it is marketing, and we don't print it that way.

Where the buyer's voice comes from

Catalog pages tell you what a greenhouse should do. Owners tell you what it does in the second winter, in a July heatwave, and in the first real windstorm. We source from:

• r/greenhouses and r/gardening, where the sizing questions, base debates, and “mine blew away / yellowed / cooked my plants” reports run in the buyers' own words
• GardenWeb and Houzz greenhouse forums, where the long-term owners tell you what they'd do differently after 15 years
• YouTube greenhouse-tour and build comments, which are more candid than the videos above them about real cost and real regret
• Facebook greenhouse-gardening groups, for the Delegator and step-up buyer's brand debates and quote-shock stories
• Verified purchase reviews for greenhouses over $2,000
• Manufacturer and dealer sales teams, who we question directly: real all-in ranges, lead times, warranty terms, base requirements, and “what do buyers regret not asking”

How we use manufacturer replies

If a manufacturer answers our questions, that can improve factual clarity. It can help us verify glazing specs, wind and snow ratings, warranty terms, base requirements, or the failure modes their service team sees most.

It does not improve placement on a roundup page. A reply is evidence. It is not a ranking boost. Access improves accuracy, never ranking.

The weaknesses database

For every brand we cover seriously, we keep a record of sourced, defensible negatives: the issue, the detail, the source, and how severe it is. A pattern of glazing panels yellowing early in owner groups, a frame that racks without the optional base, a warranty that turned out to exclude storm damage, a company that stopped answering after the sale. Raw scraped signals stay unverified until a human has read the source and confirmed the pattern. One angry post is an anecdote. Five owners with the same cracked-panel-in-two-years story is a data point.

This is why our brand pages can name what the catalog page won't.

How verdicts are formed

We judge fit, not prestige. A $15,000 heirloom glasshouse can be excellent and still wrong for someone who starts seeds in April and stores pots in winter, and a $1,600 polycarbonate kit can be the smarter buy and still wrong for a buyer in a high-wind, heavy-snow site with no proper base. The verdict explains where a greenhouse belongs, where it doesn't, and what the buyer gives up either way. It is allowed, and often correct, to recommend the mid-market option. It is also allowed to recommend no greenhouse at all: if the real goal is a heated room to work or read in, that is a garden office, and we point you to backyardoffice.guide.

What we never do

We never fabricate ratings, prices, owner quotes, or test results. If we haven't verified a number, we don't print it. If the evidence is thin, the page says so. If we're not sure, we say we're not sure.

How we handle structural safety

Structural-safety pages are written more conservatively than product pages, because a greenhouse is a structure that can fail in a storm and take your plants, your fences, or a neighbor's window with it. Wind-anchoring, snow-load, glass-safety, and overheating are treated as life-of-the-structure and horticultural-loss topics: we cite ASCE 7 and manufacturer engineering specs, we keep those pages free of product links and email capture, and we never soften the answer to keep a page commercially useful. When the safe answer is “you need a proper anchored base for that wind exposure” or “that roof pitch won't hold your snow load”, that is the answer we give.