Hoop House Construction Cost Calculator

A hoop house construction cost calculator estimates the materials and money needed to build a hoop house, a low-cost greenhouse made of bent pipe hoops covered in plastic sheeting. It takes the length, width, and height of a planned structure and returns the number of hoops, the amount of plastic film, the length of pipe, and the total material cost.

What is a hoop house?

A hoop house, also called a high tunnel or polytunnel, is a simple type of greenhouse. Curved pipes, called hoops or bows, form the frame. Plastic sheeting stretched over the hoops holds in warmth and blocks wind and rain. Unlike a heated greenhouse, a hoop house relies on passive solar heating and on vents that open by hand for cooling. Farmers and gardeners use hoop houses to start seedlings earlier in spring and keep crops growing later into fall.

How to calculate hoop house construction cost

The calculator works from three measurements entered in feet: length, width, and peak height. It combines them with two building rules: hoops spaced 4 feet apart, and three lengthwise purlins (support poles) running the length of the house. A New Mexico State University construction guide sets the hoop anchor stakes every 4 ft and runs three pipes along the length of the inside for stability.

Step 1: Count the hoops

Hoops are the curved arches spaced along the house. The calculator places one hoop every 4 feet, plus one extra hoop to close the far end.

hoop count = ceil(length ÷ 4) + 1

Step 2: Find the arc length of one hoop

A hoop is a curved arch, not a rectangle, so its pipe length equals the arc across a half-ellipse rather than the straight up-over-down path. The calculator treats half the width and the full height as the two axes of that ellipse and applies a standard ellipse-perimeter approximation to find the arc. When the height equals exactly half the width, the arch is a perfect semicircle, and the formula simplifies to pi × width ÷ 2.

Step 3: Add up the plastic sheeting

The plastic must wrap over the hoop's arc, plus about 4 feet of extra material for burying the edges in soil or clipping them down. It must also run the length of the house plus twice the height, to leave flaps that drape over each end.

plastic area = (hoop arc + 4) × (length + 2 × height)

Step 4: Add base and brace pipes

Base pipes run along the ground on both long sides of the house: base pipe length = 2 × length. Brace pipes, also called purlins, run lengthwise along the ridge and sides to tie the hoops together. The calculator uses three of them: brace pipe length = 3 × length.

Step 5: Price the materials

The calculator applies two average unit prices: $1.25 per linear foot of pipe (used for hoops, base pipes, and brace pipes) and$0.15 per square foot of plastic sheeting.

• hoops cost = hoop count × hoop arc × $1.25
• plastic cost = plastic area × $0.15
• pipes cost = (base pipe length + brace pipe length) × $1.25
• total cost = hoops cost + plastic cost + pipes cost

Example: cost to build a 20 x 10 x 7 foot hoop house

Consider a hoop house 20 feet long, 10 feet wide, and 7 feet tall at the peak.

1. Hoop count: ceil(20 ÷ 4) + 1 = 6 hoops.
2. Hoop arc: about 18.98 feet, using the ellipse formula (7 feet is taller than the 5-foot height a semicircle of this width would need).
3. Plastic area: (18.98 + 4) × (20 + 2 × 7) = 22.98 × 34 ≈ 781 square feet.
4. Base pipe length: 2 × 20 = 40 feet.
5. Brace pipe length: 3 × 20 = 60 feet.

Costs:

• Hoops: 6 × 18.98 × $1.25 ≈$142.36
• Plastic: 781 × $0.15 ≈$117.20
• Pipes: (40 + 60) × $1.25 =$125.00
• **Total: about $384.56**, or roughly$1.92 per square foot of growing space (200 square feet).

Example costs for other hoop house sizes

Figures come directly from the calculator's formulas, using $1.25 per linear foot of pipe and$0.15 per square foot of plastic. Actual prices vary by supplier and region, and the total covers materials only, not labor, end walls, doors, or ventilation.

Materials a hoop house needs

• Hoops: bent lengths of pipe, usually PVC or galvanized steel, that form the arched frame.
• Plastic sheeting: greenhouse-grade film, such as the 6 mil plastic film the NMSU guide specifies, stretched over the hoops.
• Base pipes: pipes laid along the ground on both long sides to anchor the hoops.
• Purlins (brace pipes): pipes that run the length of the house to tie the hoops together and stop them from swaying.
• Wiggle wire or clips: hardware that locks the plastic edge into a channel along the base pipes.

Many builders also add end walls with doors, roll-up sides for ventilation, and ground anchors. This calculator does not include those extras.

Frequently asked questions

How much does it cost to build a hoop house?

Material costs in this calculator generally fall between about $1 and$2 per square foot of growing space, based on its price assumptions of $1.25 per linear foot of pipe and$0.15 per square foot of plastic. An example 20 x 10 x 7 foot hoop house costs about $385 in materials. Unusually tall or narrow designs use more pipe and plastic per square foot and can cost more. The NMSU guide puts a complete high tunnel at [around$2.50 per square foot](https://pubs.nmsu.edu/_circulars/CR606.pdf). The calculator leaves out labor, end walls, doors and ventilation.

What size hoop house should I build?

Size depends on available space and how much needs to be grown. Backyard hoop houses are small, while market growers use longer and wider structures. Because hoop length grows with both width and height, wider or taller houses use more pipe and plastic per hoop, which raises the cost per hoop even before the extra square footage is counted.

How long does a hoop house last?

The plastic cover wears out before the frame, because sunlight gradually breaks down the film. UV-protected greenhouse film can last up to 12 years if cared for correctly, according to the NMSU guide. Lower-grade film needs replacing sooner.

Can someone build a hoop house without hiring a contractor?

Yes. Hoop houses are a common do-it-yourself project.

What is the difference between a hoop house and a greenhouse?

A hoop house relies on sunlight for heat and hand-operated vents for cooling. A traditional greenhouse usually adds a heating system, powered vents, and other climate controls, which raises its cost well above a hoop house's material cost. Both extend the growing season, but a heated greenhouse can support growing through cold winters more reliably than a hoop house can.

Does building a hoop house require a permit?

It depends on the location and the structure's size. Some places exempt small, unheated agricultural structures from permitting, but rules vary by city and county. Check local building codes before construction.

References

1. New Mexico State University Cooperative Extension Service. High Tunnel Hoop House Construction for New Mexico (Circular 606, revised by D. Jimenez). Circular 606 (PDF) — passive solar heating; anchor stakes every 4 ft; three lengthwise pipes for stability; 6 mil film lasting up to 12 years; about $2.50 per square foot.