DRAWING THE SHEET —
CULTIVATION / CANNABIS — THE ANCHOR BUILD
A greenhouse sealed tight enough to hold VPD through lights-off.
A few hours of near-saturated air in late flower writes off a crop worth more than the steel and the glazing combined. This house seals, so your climate system can win the night.
- VPD HELD THROUGH LIGHTS-OFF
- LIGHT-TIGHT LIGHT-DEP
- SEALED + SCREENED ENVELOPE
GENERAL EDUCATION, NOT LEGAL ADVICE — CANNABIS LAWS VARY AND CHANGE. CONFIRM EVERY REQUIREMENT WITH YOUR REGULATOR AND ATTORNEY.
CANNABIS LOADOUT — SERIES 200, LIGHT-DEP + SCREENS + TRAP
A starting point you can edit. Book prices.
01 — THE ENEMY — THE WET NIGHT
The write-off comes from a wet night.
THE FAILURE MODE, ON ONE CARD
Lights off.
AC off.
Dehumidification off.
COMFORT HVAC DEHUMIDIFIES ONLY WHILE COOLING — THE NIGHTTIME HUMIDITY SPIKE IS BUILT IN. (HPAC ENGINEERING)
Botrytis needs leaf wetness and 9–21°C air held for hours (Scott et al. 2023), and a flower room becomes both when comfort AC quits at lights-off. This building is the part of the defense you pour a foundation for.
02 — THE MECHANISM
Seal the envelope and the setpoint holds.
CLONES
0.4–0.8
kPa — soft air while roots form
VEG
0.8–1.2
kPa — building leaf and structure
LATE FLOWER
1.2–1.6
kPa — dense buds kept too dry for mold
THE STAGED VPD BAND — FULL EXPLAINER
The envelope seals, so a dehumidifier gets a room it can win in.
Insulated IMP endwalls, polycarbonate or air-gap glazing, and sealed roller doors are all lines in the build tool.
Light-dep that stays light-tight, because a leak re-vegs a crop.
A blackout curtain runs a 12/12 schedule for about $15,000 in the book, sold as a package with its climate scope.
Screened vents keep spores and thrips off the crop.
Bug screens run $850 and the light trap $2,500. See bug screens.
Cool Lock white steel keeps solar heat out of the cooling budget.
About 69% less solar heat than bare galvanized (NASA Publication 1121): why the frame is white.
PE-stamped steel clears the permit desk and the lender.
A county-sized wind load and snow load on the IBC / ASCE 7 basis, with 14-foot sidewalls. Pick the rating on The Series.
Start a cannabis build
A STARTING POINT YOU CAN EDIT.
03 — THE CLIMATE SYSTEM ITSELF
The equipment that holds VPD is quoted to your room.
~70%
OF IRRIGATION WATER TRANSPIRES BACK INTO THE AIR — 100 GAL/DAY WATERED IS ~800 PINTS/DAY TO PULL BACK OUT (HPAC ENG.)
LIGHTS-OFF
IS WHEN THE MOISTURE LOAD PEAKS — WHICH IS WHY COMFORT AC CAN'T COVER IT
HVACD
INTEGRATED HEATING, VENTILATION, AC + DEHUMIDIFICATION, SIZED TO YOUR CANOPY AND PHOTOPERIOD (PE-AUTHORED MANUFACTURER STUDY, 2023)
That system is scoped to your room and priced in your quote. Start at VPD control or read VPD, explained for buyers.
04 — THE REVENUE LEVER
Light-dep flowers the house on your schedule.
Pull a light-tight curtain to a 12/12 cycle and you flower on your calendar, multiple cycles a year. The closed curtain traps heat and moisture, so we sell light-dep as a package with matched dehumidification scoped in the quote.
Full detail: light-deprivation systems and the ROI of light-dep.
THE BOOK LINE
Interior light dep package
$14,999
CURTAIN + DRIVE, TO A 12/12 SCHEDULE. MATCHED DEHUMIDIFICATION IS SCOPED IN YOUR QUOTE.
05 — COMPLIANCE-AWARE
We build to the spec your regulator hands you.
Light-pollution / dark-sky ordinances.
Blackout screens block up to 99.9% of light both ways. Confirm your local rule.
Pesticide-residue and lab testing.
Physical pest exclusion cuts the chemical inputs standing between you and a clean result.
Security and controlled access.
Sealed door options double as biosecurity and access control. See doors.
Odor and site conditions.
Requirements vary widely; we build to the spec your consultant hands us.
Your regulator decides what's required. We build to it. General education: cannabis compliance basics.
06 — THE NIGHT, HELD
Week seven, third night of the stretch.
The lights went off two hours ago on a soaked, still night. VPD is holding at 1.4 kPabecause the system kept pulling moisture after the lamps quit. In the morning you'll walk the rows with coffee and check the crop.
07 — THE OBJECTION LEDGER
The five objections, answered at the tailgate.
“It costs five times what a hoop house does.”
It does. The extra money buys an envelope your climate system can hold a setpoint in, plus a stamp your permit desk accepts. Worked builds run $51,050 to $364,250, computed live in the cost article and the build tool.
“My AC already dehumidifies.”
Only while it cools. At lights-off it stops.
“Can my crew build it?”
Yes: 22 kinds of parts, one kind of bolt, four people, 10–14 days, no crane.
“What's the lead time?”
Steel is on a truck 7 days after your order, then 10–14 days on the pad. The list of what can stretch that is in how long a greenhouse takes.
“Will it clear my permit and my lender?”
The plans arrive PE-stamped on the IBC / ASCE 7 basis at your county's wind load and snow load, and both desks read the same stamp. See greenhouse permits.
08 — THE FIT FILTER
Who this house fits.
IT’S FOR YOU IF
You're running commercial cannabis, you sell on consistency, and a single lost flower batch would hurt more than the building costs.
IT’S NOT FOR YOU IF
You're pricing a backyard tent or a hobby room. Cheaper structures serve that better, and if the plan is comfort AC and hope, buy the climate system first.
09 — QUESTIONS, ANSWERED
What cannabis buyers ask before they call.
What is VPD and why does it matter for cannabis?
Vapor-pressure deficit is the one number that says how hard your plants are working to move water, and holding it in a staged band guards against botrytis and powdery mildew. The full explainer lives at /answers/what-is-vpd.
Can I just run air conditioning to control humidity?
A comfort AC removes moisture only while it cools, so it quits dehumidifying at lights-off, the window a flower room is most at risk. Precision VPD control needs dehumidification sized as its own job.
How much does a cannabis greenhouse cost?
The frame starts at $40,000 in our book, and worked builds run from about $51,050 to $364,250 by size and covering. The climate system is scoped and priced in your quote. Price your structure at /build.
Does the light-dep package include the dehumidification it needs?
The light-dep book line covers the curtain and drive. The dehumidification and controls that keep a blacked-out room safe ride in the climate scope we quote with you, so the curtain arrives with its safety equipment.
Do you help with cannabis compliance?
We build to the requirements your regulator and consultant hand us: light-pollution screening, sealed vestibule entry, physical pest exclusion. Legal advice stays with your attorney, so confirm every requirement with your regulator.
What wind and snow rating do I need?
Your county decides. Series 100 is 120 mph wind load. Series 200 is 140. Series 300 is 160. Snow load is 60–80 lb+ by configuration. The county lookup is on The Series page.
MORE OF THESE AT THE ANSWER DESK, INCLUDING THE HARD ONES.
Price the cannabis house today.
The preset build opens with the sealed envelope, the blackout pair, and screens already on. Edit it, price it from the book, and a Greenhouse Expert scopes the climate system to your room.
WE STAMP THE WIND LOAD AND THE SNOW LOAD.