For most ordinary agricultural greenhouses, 4 millimeters is a more common and recommended choice.
|
Character |
3.2 millimeters (usually tempered glass) |
4 millimeters (usually float or tempered glass) |
|
Strength and impact resistance |
Extremely high (because it is tempered glass) |
Relatively high (if it is float glass, it is much lower than tempered glass) |
|
security |
high |
Depending on the type |
|
Light transmittance |
Slightly lower (about 1%-2% lower) |
Slightly taller |
|
Thermal insulation performance |
Basically the same |
Basically the same |
|
Weight |
Lighter |
Slightly heavy |
|
Cost |
Usually higher |
Relatively low |
|
Common uses |
The side of the greenhouse with high lighting and safety requirements at the top |
The side facade of the greenhouse and ordinary partitions |
How to choose: Key Decision-making factors
Application location (the most crucial!)"
Greenhouse top: Tempered glass must be used. Here, 3.2mm tempered glass is a very classic and reliable choice because of its high strength, safety and light weight. 4mm tempered glass is also a great option, with excellent strength as well, but it is a bit heavier.
On the side of the greenhouse: If the budget is limited and it is not in a location prone to impact, more economical 4mm float glass can be used. If personnel safety or possible external impacts (such as flying rocks or tool collisions) are taken into account, it is recommended to use 4mm tempered or 3.2mm tempered glass.
Climatic conditions
In areas with frequent hail and strong winds: Tempered glass is preferred. The impact resistance of 3.2mm tempered glass is sufficient to withstand common hail.
Mild climate regions: There is a wider range of choices, which can be decided based on the budget.
Budget
Tight budget: Using 4mm float glass on the sides and 4mm tempered glass (or the thickness that must be used according to the specifications) on the top is a compromise solution.
With a sufficient budget and a pursuit of the best performance and safety: Using 3.2mm tempered glass throughout the process is a better choice.
Types and uses of greenhouses
Ordinary production greenhouses: Cost performance is the key, and the mixed use (top tempered, side floating) is very common.
High-end scientific research greenhouses and ornamental greenhouses: Higher requirements are placed on safety and durability, and tempered glass is usually used throughout the line.
Conclusion and Final recommendation
Don't just compare the two numbers "3.2" and "4"; it's more important to consider the type of glass (float or tempered). Tempering treatment can enhance the performance of glass more effectively than increasing its thickness.
For the top of a greenhouse, the most mainstream and safe choice is 3.2-millimeter tempered glass.It strikes the best balance among strength, safety and weight.
If cost is taken into account, a common combination is: 3.2mm or 4mm tempered glass for the top and 4mm float glass for the sides.
If the 4mm glass you see is very cheap, it is very likely not tempered glass. Under no circumstances should it be used for the top of a greenhouse.
In summary, the top recommendation is 3.2mm tempered glass, which is especially suitable for the top. 4mm glass is an economical option, but it is used on the sides or must be ensured to be a tempered version before it can be used on the top. When making a purchase, please be sure to confirm the type and purpose of the glass with the supplier.
