Blackout Light Deprivation Mushroom Tunnel Greenhouse 9m Wide 30m Long Shade Net House

Mushroom yields are decided in the first ten days, and light is the variable most growers get wrong. A pinning trigger needs a light drop to below 0.1 lux for 12 hours, not just a shade cloth thrown over a film house. This 9 m x 30 m blackout tunnel uses a 100 percent light blocking white on black film laminate with a double curtain overlap at the ridge, plus a separate 90 percent shade net for the summer, so the house can run oyster and shiitake blocks on a schedule that does not move with the seasons. The frame is 275 g/m2 hot dip galvanized, 1.0 m arch spacing, and the whole house is built to be washed down between flushes.

• 100 percent blackout cover: White on black 150 micron laminate, light tight to below 0.1 lux, with a 300 mm overlap at the ridge and double curtains on both gables.
• Separate 90 percent shade net: Runs on its own wire and pulleys, so you can shade without blacking out, and blackout without losing the summer cooling.
• Washable interior: Smooth film faces, sealed gutter and a concrete friendly base detail so the floor can be hosed and disinfected between crops.
• Insulated roof option: Double layer film with a 100 mm air gap raises the roof R value and reduces condensation drip onto blocks.
• Forced air and cooling ready: Pre framed 500 mm fan ports and evaporative cooling pad openings on the gable, sized for 20 air changes per hour.
• Hot dip galvanized frame: 275 g/m2, 1.0 m arch spacing, rated 0.40 kN/m2 wind and 0.30 kN/m2 snow.

Shade percentage and light tightness are different measurements, and suppliers often quote one when you asked for the other. A 90 percent shade net still passes daylight that will trigger pins on a bright day; a true blackout laminate brings the internal level below 0.1 lux at noon, which is the figure that matters. Check the seams as carefully as the sheet: most leaks happen at the ridge, at the gable, and where the curtain meets the end wall. This house uses a 300 mm overlap at the ridge, double layer curtains at both gables and a zip closure on the door, and we send a light test protocol with the shipment: close the house at noon and walk the inside with a lux meter at nine points. Readings below 0.1 lux pass.

Oyster mushrooms want 22 to 26 C during spawn run and 15 to 18 C for fruiting, with 85 to 90 percent relative humidity and fresh air at the same time. That combination is the hard part: closing the house to hold humidity traps CO2, and opening it to refresh air drops the humidity. Our recommendation is a 500 mm fan on a timer with a 20 percent fresh air damper, plus a fogging line on a humidistat, so air changes and humidity are controlled separately. For shiitake on logs, the house is usually run cooler at 12 to 16 C with more air, and the same frame handles both schedules. Roof insulation is worth adding if your night temperature swings more than 10 C.

Contamination is a house design problem before it is a lab problem. A smooth washable cover, a gutter that does not trap debris, and a floor that drains to one point make the difference between a two hour clean and a two day one. We detail the base with a 100 mm upstand so wash water runs inward to a drain rather than under the film. Shelving is not included as standard because growers have strong preferences, but the frame takes 25 kg per metre of purlin so four tiers of loaded blocks are within rating. Between crops, most customers steam or use a 2 percent hypochlorite wash; the film and galvanized frame both tolerate that routine.

Four people stand the 30 m frame in three days on a level pad, then the blackout cover goes on in one long day with no wind. Fit the shade net first if the site is exposed, because it protects the blackout sheet during installation. After closing up, run the light test, then the fan and fogging test, then a full wash down to check drainage. We supply a numbered panel plan and a commissioning checklist, and a technician is available by video call for the first light test if your site is far from a service partner.

Oyster and shiitake farms in China, Korea, Vietnam and Thailand running 10,000 to 40,000 blocks per cycle; specialty mushroom growers in Poland, the Netherlands and Canada; and farms in the Gulf using the house with evaporative cooling for year round production. The 9 x 30 m set loads into a 40HQ at about 33 cubic metres, with the blackout cover rolled on a core and crated separately from the frame to avoid creasing.

The blackout sheet is rolled on a core, wrapped in woven fabric and crated upright so it does not crease in transit; creases become light leaks. Frames ship in numbered bundles, hardware in labelled bags by bay. Before loading we run a light test on a sample panel assembly, check zinc weight, measure film thickness at six points, and confirm the fan port cut outs against the drawing. The frame carries a 10 year warranty and the blackout cover 3 years against delamination. Replacement panels, zip sections and curtain hardware are stocked for 10 years, and we can supply a lux meter with the first order if you do not already own one.