High Humidity in the Greenhouse
Humidity is a moisture balance: crop transpiration and evaporation from wet surfaces add water vapour, ventilation and condensation remove it. Chronic high humidity almost always means the removal side is undersized or badly controlled.
Engineering guidance is indicative and planning-level. Final system design, sizing and performance are confirmed by the appointed supplier or engineer for your site. No yield, savings or performance outcome is guaranteed.
Should I control relative humidity or humidity deficit?
Professional climate control generally uses humidity deficit (or vapour pressure deficit) because it reflects the air's actual capacity to absorb moisture at a given temperature, whereas relative humidity alone can mislead across a day-night cycle.
Likely causes
Vents closed for temperature protection at night trap moisture.
Classic control pairs minimum pipe heat with a vent crack to move moisture out.
Excess drainage and standing water raise the evaporative load.
Single-skin coverings and thermal bridges drip onto the crop.
In tropical regions the outside air itself is near saturation.
Quantify it
Systems that resolve it
Forced exchange and controlled vent positions.
Humidity-deficit-based control rather than RH setpoints alone.
Screens, air circulation fans and pipe heating.
Distributed sensors reveal wet zones and stratification.
Reduce over-irrigation feeding the moisture load.
Frequently asked questions
Move high humidity in the greenhouse into a structured RFQ
Editorial · not a sales pitchThis page is reference material. When you are ready to convert planning into pricing, a structured RFQ replaces weeks of unstructured email with days of comparable, supplier-neutral offers.
The facts a complete, supplier-neutral request on this topic includes. Use it as a checklist before submitting.
- Covered area (m² or ha), bay/gutter layout preference and target gutter height
- Site location, altitude and design loads (wind, snow, seismic) if known
- Crop and production system (soil, substrate, hydroponic, nursery)
- Covering choice: polyethylene film, polycarbonate or glass — and expected lifetime
- Climate scope: ventilation, screens, heating, cooling/pad-fan, CO₂, controls
- Irrigation/fertigation scope and water source quality
- Target commissioning date, phasing and budget band (USD $250K+)
- Incoterms, destination port/site and who handles civil works and erection
- Site plan or coordinates with plot dimensions
- Soil/water analysis where available
- Any existing concept drawing, BOQ or previous supplier offer
Opens the RFQ Builder pre-scoped as a greenhouse project so suppliers quote structure, covering, climate and irrigation on the same basis. You stay in control — nothing is submitted until you review and confirm.
Free to submit · supplier-neutral · reviewed by a specialist before any supplier is contacted.
What to do next
Most organizations move through these four steps in order. Each one can be started independently, and nothing is shared with suppliers until you approve the scope.
Turn your project scope into one supplier-neutral request qualified manufacturers can price consistently.
Site, water, energy, permits and documentation — the readiness work lenders and EPC contractors expect before quoting.
Debt, leasing, blended and export-credit structures for commercial agriculture CAPEX, assessed alongside the technical scope.
Supplier-neutral guidance on greenhouses, CEA, irrigation, nurseries, packing houses and project finance.
How this guidance is produced
We do not manufacture equipment and do not represent a fixed vendor list. Guidance reflects the project, not a catalogue.
Content is prepared and reviewed by sourcing specialists working on live commercial agriculture projects, supported by proprietary technology.
Practice drawn from greenhouse, CEA, irrigation, nursery, packing-house and processing projects across multiple climates and regulatory environments.
Project details stay private. Nothing is published, listed or shared with suppliers without your approval.
Editorial approach and company background: About SeedMatch Group.
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