This is a frame sold by the tonne as much as by the metre, which is why the pipe table matters more than the picture. Pre-galvanized tube runs from 21.3 to 114.3 mm, hot dip from 21.3 to 600, with zinc at 5 to 25 micron or 35 to 200 depending on which you buy. Cover is PE, PO or panda film at 120 to 200 micron, and a film rolling machine comes with it. It is also the easiest shape to extend later, because the next bay is the same bay.
A single arch tunnel is the plainest structure in the catalogue, and that is the point: it is bought by growers who want covered area at the lowest cost per square metre and are willing to do the work themselves. What separates one supplier from another at this level is the pipe, the zinc and the film, not the shape. It is part of the tunnel greenhouse range on this site.
Panda film is a two-sided cover: white on one face and black on the other. The white face reflects light back into the house, which is useful on a crop grown low to the ground, and the black face blocks light and weed growth where the film is used as a skirt or a floor. On a tunnel it is usually ordered for the lower section rather than the whole roof.
For a normal vegetable house, PE or PO at 120 to 200 micron is the standard answer. Panda is the option for growers who want reflected light at bench level, and it is quoted alongside the standard film rather than instead of it.
Two pipe families are supplied. Pre-galvanized tube runs from 21.3 to 114.3 mm with a zinc coating of 5 to 25 micron and a wall of 0.6 to 2.5 mm. Hot dip galvanized tube runs from 21.3 to 600 mm with 35 to 200 micron of zinc. The second is the one to specify on a coastal or high-rainfall site, and the price difference is real.
Steel grades are Q235, Q345, S235JR, S275JR, STK400, STK500 and S355JR, to BS1139, EN1039, EN10219, JIS G3444, GB/T 3091 and ASTM A53. On a quotation, the grade and the zinc weight are the two lines that tell you what you are actually buying.
| Product type | Single arch greenhouse |
| Pre-galvanized pipe | 21.3 to 114.3 mm, wall 0.6 to 2.5 mm |
| Hot dip pipe | 21.3 to 600 mm, wall 0.8 to 25 mm |
| Zinc coating | 5 to 25 micron pre-galvanized, 35 to 200 micron hot dip |
| Steel grade | Q235 / Q345 / S235JR / S275JR / STK400 / STK500 / S355JR |
| Pipe standard | BS1139, EN1039, EN10219, JIS G3444, ASTM A53, GB/T 3091 |
| Cover material | PE, PO or panda film |
| Film thickness | 120 / 150 / 200 micron, or to order |
| Accessory | Film rolling machine |
| Minimum order | 2 tonnes |
| Delivery | Within 25 days |
| Payment | T/T or L/C |
The rolling machine is the part that decides whether a side wall is opened once a day or never. It is a geared drum that winds the film onto a tube along the wall, and it is fitted at the base rail on each side of the house. On a long tunnel it is the difference between ventilation being a habit and being a chore.
The minimum order is two tonnes, which on this type of house is usually a tunnel plus a spare set of arches, or two short houses. Delivery is quoted within twenty-five days, payment by T/T or L/C. Because the order is priced by weight, the span and the pipe diameter move the number more than the length does, and it is worth asking for the weight breakdown before comparing two quotations.
Agricultural engineering and protected cultivation research is published by UC Davis, and commercial growing coverage by The Grower.
It is used for vegetables, fruit and cut flowers, and for the low-cost end of commercial growing: rented land, seasonal blocks and growers adding a house a year rather than building a range at once. The single arch is also the easiest shape to extend later, because the next bay is the same bay.
A house with side and roof vents on the same frame is described on the vented single span tunnel page, and a gothic hoop house on the gothic hoop house page.
Film suits low-cost tunnels on 3-5 year replacement cycles. Glass delivers the highest light transmission and the longest lifespan, at the highest cost. PC sheet insulates better than film and suits cold or high-humidity climates. The right choice depends on climate, crop and budget.
Ziyang Bozong Greenhouse Industry Co., Ltd. is a manufacturer based in Ziyang, Sichuan, China. We produce the hot-dip galvanized steel frame in-house, cutting and drilling to drawing, and supply covering materials, ventilation, cooling and irrigation systems as one coordinated package.
Send your growing area, span and length, crop type and local climate. If you already have a layout drawing, that is enough to start. Our engineers then return a quotation with a structure drawing and a bill of materials.
The hot-dip galvanized steel frame is designed for a 15-20 year service life in normal agricultural environments, with a double-sided zinc coating of 200-275 g/m². Film covers are replaced every 3-5 years, while glass and PC panels carry their own manufacturer warranties.
Panda film is white on one face and black on the other. The white face reflects light back into the crop and the black face blocks light and weeds. On a tunnel it is usually specified for the lower section rather than the whole roof, alongside PE or PO film.
Two tonnes, which is roughly a tunnel plus a spare arch set or two short houses. Delivery is quoted within twenty-five days, payment by T/T or L/C. Because pricing is by weight, span and pipe diameter move the number more than length does.
