— Cultivation HVAC & Controls

A grow room is a climate problem before it's an HVAC problem.

For cannabis operators, indoor farms, greenhouses, research facilities — every controlled environment where climate is the crop. Argus certification. Forty years of mechanical HVAC. Both trades, one crew. Most controls integrators don't self-perform mechanical. Most mechanical contractors don't carry Argus. We do.

Talk to us about a grow operation See our BAS work

Indoor agriculture climate control — HVACD and Argus controls under one crew

— The category

Cannabis. Produce. Research. Vertical farms.

Different buildings, same discipline — climate control tight enough to serve a live crop.

Controlled environment agriculture is a category, not a market. What ties it together is the room itself — sealed envelope, live plants, precision control on temperature, humidity, air movement, CO2, and light. "HVAC that happens to be in a grow room" is where most projects go wrong. The load looks like an office building until you add the transpiration curve. Then it doesn't look like anything you've seen before.

— Sub-markets we serve

Four buildings. One discipline.

Cannabis grow operation — environmental control across flower and veg rooms

Cannabis grow operations.

Flower rooms, veg rooms, drying rooms. Regulated environments where temperature, humidity, VPD, CO2, and light schedules directly drive yield. Most projects are retrofits — old warehouses and industrial space — which means the mechanical envelope is fighting the process from day one.

Research and biopharma facility — controlled environment including cold storage and vault refrigeration

Research + biopharma.

University plant science, USDA research, tissue-culture labs, seed-genetics facilities, cold-storage vaults. Tighter control tolerances than commercial grow. Regulated data-logging requirements. The mechanical side has to serve the science, not the harvest.

Commercial greenhouse ventilation — produce and ornamentals climate control

Commercial greenhouses.

Produce, ornamentals, propagation. Semi-open envelopes with active climate control. Fertigation and light supplementation matter as much as the mechanical side. Volume operations — the math is on cost per square foot, not per plant.

Vertical farm — multi-tier hydroponic HVAC and climate control

Vertical farms + indoor ag.

Hydroponic, aeroponic, aquaponic. Fully-sealed multi-tier growing. The mechanical problem is dense and repeatable — one zone design multiplied across floors. The controls problem is coordination — every tier talking to every other tier.

— The combination

One crew. Both trades. Under one roof.

Most controls integrators don't self-perform mechanical. They subcontract the HVAC or wait for the mechanical contractor to finish, then come in to program. Most mechanical contractors don't carry Argus certification. They install the equipment and hand off to whoever's doing the controls.

That handoff is where CEA projects lose money.

The controls team needs the mechanical sized right — for actual transpiration loads, not office-building assumptions. The mechanical team needs to know the controls sequence — because the sequence dictates equipment cycling, redundancy needs, and sensor placement. When they're different companies with different priorities, coordination gets expensive. Schedules slip. Sizing arguments happen after equipment is already bought. The owner watches from the middle.

We do both. Same people. Same schedule. Same accountability.

Athena crew on site — mechanical HVACD and Argus controls under one scope

— Capabilities

What we install. What we control.

The mechanical side and the controls side, side by side. Neither delegated to a subcontractor.

— The mechanical (HVACD)

Equipment we specify and install.

Desert Aire (GrowAire / GreenAire / DriCure).

Purpose-built integrated HVACD units for indoor cultivation. Modulating hot-gas reheat coils that use waste heat from dehumidification instead of burning new energy. DriCure specifically for drying rooms — a room type most controls integrators ignore.

Bard wall-mounts.

Wall-mounted split systems for smaller cannabis facilities and modular buildouts. Fast install, dense capacity per unit. Works when roof-mounted RTUs aren't an option. Usually paired with dedicated dehumidification.

AAON rooftop units.

Custom-configured RTUs for larger CEA facilities. Sized for actual latent load, not office-building assumptions. When the roof can carry the weight and the building is new construction, AAON delivers.

Fanwall arrays.

Modular blower arrays for high-airflow requirements. Redundant, quieter at part-load, efficient across a wide capacity range. Retrofits into existing air handlers without full unit replacement.

VRF (with a caveat).

Great for multi-zone commercial buildings. Not the right primary tool for a grow room — VRF is designed for sensible cooling, not moisture. Independent Desert Aire studies show VRF-plus-standalone-dehumidifier configurations use 15% more energy than integrated HVACD.

UV-C sterilization.

In-duct UV-C lamps for pathogen suppression. Coil-surface UV for biofilm control. A layer on top of filtration and IPM — especially useful in propagation and tissue-culture rooms.

— The controls (Argus)

Climate variables we manage.

Temperature.

Setpoints by growth stage. Cannabis flower typically 68–80°F, tighter for research, wider for commercial produce. Argus schedules per zone, per stage of the harvest cycle.

Humidity.

First-class setpoint, not downstream artifact. 40–70% RH depending on stage. Coupled directly to dehumidification demand. Mold above 70%. Dehydration below 40%.

VPD.

Vapor pressure deficit — temperature and humidity coupled as the plant experiences them. The single most important controls metric in a working grow room. Managed as a first-class setpoint.

Air movement.

Uniform airflow across the canopy is the difference between one bad plant and one bad batch. Fanwalls, HAF fans, canopy circulation. Argus coordinates fan zones so micro-climates don't form.

CO2 enrichment.

Target ppm typically 800–1500 during light hours. Injection sequenced by Argus. Ventilation and worker exposure limits enforced on schedule. Purge cycles between phases.

Light.

Spectrum, DLI, photoperiod, sunrise/sunset ramps. Programmed per zone in Argus. LED and HID/HPS shift the HVAC load calc — the mechanical design has to know which fixtures are in the room.

Dehumidification stack in a cannabis grow room — latent-load-first mechanical design

— The mechanical challenge

Dehumidification is the first hard problem. Everyone's second.

Plants transpire. Water goes up through the leaves and into the air. In a full-cycle cannabis flower room, that means 150–200 pounds of water per hour per 1,000 square feet of canopy. That is the mechanical challenge. Everything downstream depends on getting it right.

Traditional HVAC calcs miss this. They size for sensible load — the temperature swing — and treat humidity as a downstream artifact. In a grow room, that math produces an underdesigned dehumidification stack and a compressor cycling itself to death. Then a mold event happens. Then somebody calls us.

The other one is light-heat coupling. LED fixtures shift the load calc one way. HID and HPS fixtures shift it a different way. The mechanical design has to know what fixtures are in the room, in what quantity, on what schedule. If the fixtures change halfway through construction — which they always do — the HVACD has to accommodate. Only in-house mechanical can move that fast.

Make no mistake: the mechanical is the first design decision. Everything else follows it.

— What we bring

The credentials, the trades, the service department.

Argus certification.

Manufacturer-trained on the platform. Our controls engineers know Argus the way they know Schneider EcoStruxure or Niagara — every day, in the field, not just in the training module.

Mechanical + controls in-house.

Both trades under one roof, one crew, one schedule. No coordination tax between contractors. No sizing arguments after equipment has been bought.

Design-build capability.

Through our general contracting arm. The shell, the mechanical, the controls — specified together, built together. Not three vendors that met at the pre-construction meeting.

Service department.

Grow rooms need ongoing tuning. Recipes change. Fixtures change. Crops change. For the record: our service team owns the lifecycle, not just the install.

— See it in action

Two videos worth the time.

Argus Axia — Grow Control Platform

Climate Control in Indoor Agriculture

— Insights

Reading from the field.

Access Expert or Security Expert? A field guide to Schneider’s two access control products (and who should install them)

Two Schneider access control products, one deep EcoStruxure Building Operation integration, one common installation mistake. A plain-English guide to Access Expert vs.…

Cloud-managed BMS, explained — what Neeve actually does.

What a cloud-managed BMS actually is, what Neeve actually does, and where it fits — from an integrator that runs it on…

Twisted-pair adapters, compared — the open T1L standard vs. Schneider’s free topology.

Which twisted-pair adapter fits your building? A side-by-side of the open T1L standard, Schneider's free-topology approach, and where each one belongs.

Reuse the wiring you already have — upgrading building controls without a rewire.

How the Schneider SpaceLogic Twisted Pair Adapter lets you upgrade to BACnet/IP without pulling new cable — and where its limits sit.

— Reference material

The tables behind the recommendations.

For the deep readers — environmental targets, system comparisons, and the indoor-versus-greenhouse framework. Expand any panel for the detail.

Environmental targets by growth stage

Stage	Temperature	Humidity (RH)	VPD	CO2 (ppm)	Photoperiod
Seedling / Clone	72–78°F	65–70%	0.4–0.8 kPa	400–800	18 / 6
Vegetative	70–85°F	60–70%	0.8–1.2 kPa	800–1200	18 / 6
Early Flower	68–80°F	55–65%	1.0–1.3 kPa	1200–1500	12 / 12
Late Flower	65–75°F	40–50%	1.2–1.6 kPa	1000–1400	12 / 12
Drying	60–65°F	55–60%	—	ambient	Dark
Curing	60–70°F	58–62%	—	ambient	Dark

Sources: Desert Aire application notes AN25–AN35, Argus grow recipe libraries, and cannabis cultivation guidance from Anvil Agronomics / Zartarian Engineering (2023 cultivation HVACD study). Ranges shift by cultivar, growth medium, and light intensity.

Climate control system types compared

System type	Best fit	Strength	Weakness
Split systems (mini-split)	Small setups, single zone, hobby-scale	Cheap, simple install, ductless	No native humidity control, limited capacity
Packaged rooftop (RTU)	Warehouses, mid-size retrofits	All-in-one, roof-mounted, familiar to most contractors	Not designed for CEA latent load without upgrades
Bard wall-mount	Small-to-mid cannabis retrofits, modular buildouts	Fast install, dense capacity per unit	Needs dedicated dehumidification alongside
VRF	Multi-zone comfort buildings	Precision sensible cooling, energy-efficient at partial load	Weak on moisture — needs standalone dehumidifiers, wider swings
Chilled water	Large multi-zone operations, vertical farms at scale	Industrial capacity, stable, deep zoning	High capital cost, complex install and commissioning
Integrated HVACD (Desert Aire class)	Commercial cannabis, high-density CEA, purpose-built facilities	Sensible + latent in one package, lowest total cost per crop cycle	Higher upfront capital, requires HVACD-fluent designer

Comparison synthesized from Desert Aire's Cultivation HVACD System Comparison Study (2023, with Anvil Agronomics + Zartarian Engineering), Indoor Farming Hub HVAC system guidance, and Athena field experience.

Indoor vs. greenhouse decision framework

Factor	Indoor (sealed)	Greenhouse
Setup cost	Higher — full envelope, mechanical, controls, lighting	Lower — envelope, supplemental mechanical, some lighting
Energy cost	Higher — all light and all HVACD is powered	Lower — sun does most of the lighting
Environmental control	Full — every variable programmable	Partial — natural weather influences setpoints
Yield consistency	High — no seasonal variation	Moderate — seasonal effects on cycle timing
Cannabinoid / terpene profile	Precise, tuned via CO2 and light spectrum	Broader profile from full-spectrum sunlight
Best when	Cannabis with tight quality targets, research, biopharma, indoor produce	Commercial produce, ornamentals, propagation, cost-focused operations

Comparison drawn from Fluence Bioengineering and Amazol cannabis cultivation guidance. The choice usually comes down to product positioning (premium vs. volume) and local energy economics.

— Next step

Have a cultivation project?

Cannabis, greenhouse, vertical farm, research facility. New build, retrofit, ongoing tuning — whatever the stage, we can walk it. Argus controls plus the mechanical to back them. No queue. Real people.

Talk to us Or request service

— Other expertise

Explore the rest of what we do.

— Building Automation