Hoop greenhouses: Stretch the season at both ends · Alt Ordo Systems Guide
A hoop house (also called a high tunnel or polytunnel) is a row of steel hoops covered in greenhouse film, with soil for a floor and no heater. The sun warms it by day, roll-up sides let the heat out, and a layer of row cover inside holds a few degrees at night. That modest shelter is enough to plant tomatoes weeks earlier, pick greens through winter and keep rain, hail and many pests off the crop. It is the cheapest square foot of protected growing space you can build.
This guide helps you pick, size, build and run an unheated hoop house that puts tomatoes on the table a month early and keeps salad greens coming through the dark of winter, on a budget from a few hundred dollars up.
What's inside. 19 pages in 9 chapters (At a glance, Where it works, How it works, Size it, Parts and cost, Build it, Run it, Rules and permits, How it connects), then the sources and a notes page. 9 numbered figures drawn for this guide, including a fit map of every US county. You also get a worked example with a fill-in worksheet, 11 numbered steps, a year-round calendar, and a troubleshooting table.
Three builds, costed line by line (typical US prices, October 2026):
- Bare-bones: ≈ $400–$550
- Standard: ≈ $1,520–$2,290
- Comfortable: ≈ $5,100–$7,300
Sourced and fact-checked. Facts and figures are cited to the 21 sources listed at the back, and the whole guide was fact-checked before release. General guidance, not engineering advice: your county and a qualified pro have the last word on your site.
Pairs with other Alt Ordo Systems Guides: The off-grid vegetable garden; Roof rainwater catchment; Composting; Canning and food preservation. For your county's permits and rules, see our county and state guides.
Instant PDF download. After checkout you get a download link by email. Letter-size pages, made to read on screen or print at home.