Short answer: Compare greenhouse quotations by design basis and supply boundary, not only by total price. Confirm the same area, dimensions, climate loads, steel specification, covering, ventilation, cooling, irrigation, automation, packing, installation support, warranty and exclusions before deciding which offer is lower.
Two quotations may use the same words while including different structures and systems. One offer may include gutters, insect net, cooling, irrigation and packing, while another may list only the frame and film. A low total can reflect a smaller scope rather than better value. Buyers should build one comparison sheet based on the required project outcome.
| Comparison item | What to confirm |
|---|---|
| Site and climate | City, wind, snow, temperature, humidity, rainfall and corrosion conditions |
| Layout | Total area, span, bay, gutter height, number of blocks, doors and service areas |
| Crop | Crop type, production season, growing system and hanging load |
| Structure | Steel grade, main section sizes, coating or galvanizing, bracing and foundation interface |
| Covering | Film layers and thickness, polycarbonate specification or glass type and fixing system |
| Climate systems | Ventilation, shading, fans, cooling pads, heating, fogging, screens and controls |
A bill of materials should identify the major structure and system quantities. It does not need to reveal confidential manufacturing details, but it should be specific enough to show what is included. Ask suppliers to identify optional items separately and state which items are supplied locally.
Steel weight alone is not a complete comparison, but missing section sizes and coating information are warning signs. Confirm the design load, column and truss sections, galvanizing or coating method, connector type and fasteners. For covering, compare usable specification, fixing accessories, warranty source and replacement practicality.
Confirm opening area and operation method for ventilation. For cooling, compare fan quantity, pad area, pump and water circulation scope. For irrigation and hydroponics, compare filters, tanks, dosing, valves, pipes, sensors and controls. A quotation that says complete irrigation system without a component list is difficult to evaluate.
Ask whether the quotation includes export packing, container loading plan, packing marks and estimated container quantity. The estimate can change after final design. Confirm the destination port, trade term and whether freight is a current estimate or included amount. Review container quantity only after the bill of materials is stable.
Separate the price and responsibilities for drawings, remote support, on-site supervision, local labor and full installation. Confirm whether commissioning covers motors, sensors, climate controls, irrigation and operator training. Travel and accommodation assumptions should be visible instead of hidden in a general service line.
Ask for warranty scope by component because steel, film, motors, controllers and pumps may have different conditions. Confirm the initial spare-parts package, recommended consumables and response process. Read the exclusions carefully: foundations, local electricity, water treatment, permits, taxes, unloading and lifting are often outside the supplier scope unless listed.
Design basis is complete and matches the site
Scope and exclusions are specific
Main technical specifications are visible
Drawings and bill of materials support the price
Packing and shipping assumptions are explained
Installation and commissioning responsibilities are clear
Warranty and spare parts are stated by system
Supplier answers technical questions consistently
Not until all suppliers are quoting the same design basis and supply boundary. A cheaper quotation may omit systems, packing or technical support that another offer includes.
Price per square meter is useful only when structure, covering, systems, loads, height and service scope are similar. It is not a complete purchasing standard.
Send one written clarification list to every supplier and request a revised scope table. Do not rely only on verbal explanations.
After the layout and bill of materials are confirmed. Early estimates can change when steel, covering or equipment changes.
Use the China greenhouse supplier evaluation guide and the quotation request checklist together with this comparison method.
For a scope-based quotation, send the same project information to NSR Greenhouse through the contact page.