Hoop House Calculator
Plan the frame and cover for a hoop house, low tunnel or high tunnel. Enter the width (span), length and peak height, pick a hoop spacing and your pipe stock length, and get the bent pipe length per hoop, the number of hoops, the total pipe and sticks to buy, and the greenhouse-poly cover size and area — with an optional cost, by-spacing and by-width tables, and a downloadable PDF.
| Spacing | Hoops | Total pipe | Sticks |
|---|---|---|---|
| Enter a space to compare | |||
| Width | Pipe / hoop | Total pipe | Cover area |
|---|---|---|---|
| Enter a space to compare | |||
How to use the hoop house calculator
Four quick steps turn your hoop house size into a frame and cover shopping list — pipe per hoop, number of hoops, sticks to buy and poly area — with by-spacing and by-width tables and a downloadable report.
Enter the size
Give the width (span), length and peak height of the house in feet.
Pick hoop spacing
Choose 2, 3, 4 or 6 ft on center — closer for snow, wider for light duty.
Set pipe & cover
Enter your pipe stick length, the cover overhang, and prices if you want a cost.
Read results & save a PDF
Get hoops, pipe, sticks and poly, compare spacings and widths — then download a report.
How the hoop house materials are calculated
Each hoop is a circular arc through the span and peak; the hoop count comes from the length and spacing, and the cover wraps the arc plus an overhang. Here is the exact math the calculator runs.
Worked example — 12 × 24 ft hoop house, 7 ft peak, hoops 4 ft on center, 10 ft pipe sticks, 2 ft cover overhang
Radius: (6² + 7²) ÷ (2 × 7) ≈ 6.07 ft · Pipe per hoop: ≈ 20.94 ft
Hoops: floor(24 ÷ 4) + 1 = 7 · Total pipe: 7 × 20.94 ≈ 146.6 ft · Sticks: ceil(146.6 ÷ 10) = 15
Cover: (20.94 + 4) × (24 + 4) ≈ 24.9 × 28 ft · Area: ≈ 698 sq ft · Ground: 12 × 24 = 288 sq ft
≈ 7 hoops, 147 ft of pipe (15 sticks of 10 ft) and about 698 sq ft of greenhouse poly.
Hoop house reference charts
Handy lookups for how spacing, width and peak height change the pipe and cover you need. Always add extra for legs, splices and offcuts.
| Spacing | Hoops | Total pipe | 10 ft sticks | Best for |
|---|---|---|---|---|
| 2 ft | 13 | 272.2 ft | 28 | Heavy snow |
| 3 ft | 9 | 188.4 ft | 19 | Snow and wind |
| 4 ft | 7 | 146.6 ft | 15 | Typical home use |
| 6 ft | 5 | 104.7 ft | 11 | Light duty, mild weather |
Sticks are total pipe ÷ stock length, rounded up, assuming offcuts are reused.
| Width | Pipe / hoop | Total pipe | Cover area |
|---|---|---|---|
| 8 ft | 19.53 ft | 136.7 ft | 659 sq ft |
| 10 ft | 20.10 ft | 140.7 ft | 675 sq ft |
| 12 ft | 20.94 ft | 146.6 ft | 698 sq ft |
| 14 ft | 21.99 ft | 153.9 ft | 728 sq ft |
| 16 ft | 23.21 ft | 162.5 ft | 762 sq ft |
| 20 ft | 26.00 ft | 182.0 ft | 840 sq ft |
A 14 ft width with a 7 ft peak is a true semicircle. End walls are not included in the cover area.
| Peak height | Pipe / hoop | Shape |
|---|---|---|
| 4 ft | 15.29 ft | Low, flatter arch |
| 5 ft | 16.95 ft | Low arch |
| 6 ft | 18.85 ft | Semicircle |
| 7 ft | 20.94 ft | Tall arch, more headroom |
| 8 ft | 23.18 ft | Tall arch, sheds snow |
Bent arc length only — add extra for legs set into ground posts and for splice overlap.
Everything the calculator works out
Three dimensions and a spacing give you the full frame and cover picture — hoops, pipe, sticks and poly — with an optional cost and side-by-side comparisons.
Key figures behind the estimate
Built for any hoop structure
From a single low tunnel to a walk-in high tunnel, the same calculator turns your dimensions into a materials list.
Building a walk-in hoop house to start seeds early and grow later into the fall, and wants a clear shopping list.
- Enter width, length, peak
- Keep 4 ft spacing
- Read sticks and poly
Planning a larger tunnel for production beds and needs to compare widths and spacings before ordering steel.
- Compare widths
- Tighten spacing for snow
- Add prices for a budget
Covering a raised bed or row with a short tunnel against frost and pests, using conduit or PVC hoops.
- Use a 2–4 ft peak
- Set your stick length
- Read cover size
7 things to know about building a hoop house
A few details keep a hoop house estimate accurate and the frame standing through wind and snow.
Hoop house calculator FAQ
The hoop, pipe and cover questions people ask most when planning a hoop house or tunnel.
Each hoop is a curved arc running from one ground edge, up over the peak and down to the other side, so its length is longer than the width. This calculator treats the hoop as part of a circle: the radius is (a² + s²) ÷ 2s, where a is half the width and s is the peak height, and the arc length follows from that radius and the angle it sweeps.
When the peak height is exactly half the width, the hoop is a semicircle and the length is simply π × width ÷ 2. A 12-foot-wide house with a 6-foot peak needs about 18.85 feet of pipe per hoop. Raising the peak to 7 feet lengthens each hoop to about 20.94 feet.
These figures are the bent arc only. Add extra for the legs that go into ground posts or are buried, and for any overlap where two pipes are joined.
About 4 feet on center is the most common spacing for home hoop houses and works well where snow is light to moderate. In areas with heavy snow, closer spacing of 2 to 3 feet makes the frame much stronger, while 6 feet is only suitable for light-duty, seasonal covers in mild weather.
Closer spacing means more hoops and more pipe. For a 24-foot-long house with 12-foot-wide, 7-foot-tall hoops, 4-foot spacing needs 7 hoops and about 147 feet of pipe, while 2-foot spacing needs 13 hoops and about 272 feet.
Wind exposure, the pipe you use and whether you add purlins or bracing all affect how far apart hoops can safely go, so lean toward closer spacing if you are unsure.
Divide the length of the house by the hoop spacing, round down, and add one for the hoop at the far end. A 24-foot-long house at 4 feet on center needs 24 ÷ 4 = 6, plus 1, for a total of 7 hoops.
The extra hoop matters because hoops sit at both ends of the house, not just between them. A 24-foot house at 3-foot spacing needs 9 hoops, and at 2-foot spacing it needs 13.
If the length does not divide evenly by the spacing, the last gap will be a little shorter than the rest, which is fine and slightly strengthens that end.
The cover has to reach over the full arc of the hoops and along the full length, plus an overhang on every edge so it can be buried, clamped or fastened to a baseboard. This calculator works it out as (arc length + 2 × overhang) × (length + 2 × overhang).
For a 12 by 24 foot house with a 7-foot peak and a 2-foot overhang, that is about 24.9 by 28 feet, or roughly 698 square feet of poly.
Greenhouse film is sold in set roll widths and lengths, so round up to the next size available. The end walls are not included in this figure and need their own film or panels.
They are all the same basic idea, hoops covered with plastic or fabric, at different sizes. A low tunnel is a small row cover, usually only 2 to 4 feet tall, that you reach into from the side to protect a single bed.
A hoop house is tall enough to walk inside, typically around 10 to 16 feet wide with a 6- to 9-foot peak, and is the most common size for home gardens. A high tunnel is a larger version used by market growers and farms, often wide and tall enough for wheelbarrows or small equipment.
This calculator works for all three. Enter the width, length and peak height of the structure you plan to build.
Steel EMT electrical conduit is a popular choice for home hoop houses. It comes in 10-foot sticks, bends cleanly with an inexpensive hoop bender and is strong enough to hold its shape under moderate snow and wind.
PVC pipe is cheaper, often sold in 20-foot lengths and easy to bend by hand, but it flexes more, can sag under snow and breaks down in sunlight over time. Galvanized steel greenhouse tubing is the most durable option and is common for larger high tunnels.
Enter the length of the sticks you plan to buy as the pipe stock length so the calculator can estimate how many to purchase.
A peak height equal to half the width gives a true semicircle, which is the simplest shape and uses the least pipe. A taller peak gives you more headroom near the sides and helps snow slide off rather than pile up on top.
Height has a big effect on pipe length. For a 12-foot-wide house, each hoop needs about 16.95 feet of pipe with a 5-foot peak, 18.85 feet with a 6-foot peak, 20.94 feet with a 7-foot peak and 23.18 feet with an 8-foot peak.
Choose a height that lets you stand and work comfortably along the center, and check that the hoop length still works with the pipe stock you plan to buy.
No. The calculator divides the total pipe length by your stock length and rounds up, which assumes every offcut can be reused. In practice, each hoop is usually made from whole sticks joined end to end, so leftover pieces are often wasted.
For example, a 20.94-foot hoop is just longer than two 10-foot sticks, so each hoop really needs three sticks. Seven hoops would then use 21 sticks rather than the 15 the total length suggests. Lowering the peak slightly, or using longer stock, can avoid that third stick.
Also allow extra for ground posts, legs driven into the soil, splice overlap and any purlins or bracing, which are not included in this estimate.
Estimate only — frame and cover material. This calculator works in US units (feet). Each hoop is the bent arc of a circular profile through the span and peak, where R = (a² + s²) ÷ 2s with a = width ÷ 2 and s = peak height. Hoops = floor(length ÷ spacing) + 1, pipe sticks are total pipe ÷ stock length rounded up, and the cover is (arc + 2 × overhang) × (length + 2 × overhang). Allow extra for bending springback, legs set into the ground, splice overlap and offcuts. Baseboards, end walls, doors, purlins, ground posts, clips and fasteners are not included. Confirm your design against your materials and local snow and wind loads, and check any local rules for garden structures before you build. For planning purposes only.