Custom aluminum starts with the function it performs within the greenhouse system

An aluminium profile in a greenhouse is never a standalone component. It forms part of a larger system in which structural integrity, light transmission, water management, ventilation, automation and installation must work together seamlessly. That is precisely why custom aluminium does not begin with the shape of the profile itself, but with the function it needs to perform within the greenhouse system.

For greenhouse builders and suppliers of horticultural technology, this presents an important engineering challenge. A profile must be strong enough for its intended application, while using material only where it is technically required. A slimmer profile geometry can contribute to increased light transmission within the greenhouse, yet the profile must still withstand the loads imposed by the overall system. Water must be managed and drained in a controlled manner, while in automated applications dimensions, straightness and tolerances can directly influence the reliability of moving systems.

According to BOAL Extrusion in De Lier, the real value of custom aluminium lies in aligning profile design with system functionality from the earliest stages of development.

Not a single requirement, but a combination of functions

Optimising an aluminium profile for one specific property is relatively straightforward. The technical challenge arises when multiple requirements must be fulfilled simultaneously.

For example, reducing wall thickness can save material and weight, but the profile must remain reliably extrudable while retaining sufficient strength. A slimmer cross-section may improve light transmission, yet the same geometry must also withstand the loads for which the greenhouse system has been designed.

Water management introduces another set of considerations. The geometry of greenhouse gutters, condensation gutters, drainage chambers, drip edges, joints and connections partly determines where rainwater and condensate are directed and how they are subsequently drained away. In some cases, a profile can integrate several functions that would otherwise require separate components or additional connections.

As a result, the design question shifts from "How do we manufacture this profile?" to "What does this profile need to do within the system?"

Automation increases the importance of repeatability

This approach becomes even more relevant as greenhouse operations become increasingly automated. Growing benches, shuttles and internal transport systems move repeatedly over long distances and must consistently position themselves with precision.

A minor deviation in a single profile may be barely noticeable on its own. However, when the same variation is repeated across multiple profiles or throughout an extended installation, the cumulative effect can become significant. Dimensions, straightness, tolerances, connections and repeatability therefore become more than product specifications; they become factors that directly influence the performance of the entire system.

This also requires attention to the production process itself. Alloy selection, heat treatment, extrusion, cut length and any subsequent machining operations can collectively affect the final result.

© BOAL Extrusion

Efficient material use starts with technical functionality

When it comes to more sustainable material use, the discussion does not begin solely with the choice of recycled or low-carbon aluminium. Profile design itself also plays a crucial role.

The key question is where aluminium is technically required. In some areas, material can be reduced locally, while elsewhere an additional rib, chamber or modified geometry may be necessary to achieve the required stiffness or functionality.

A few grams of aluminium per metre may seem insignificant, but across large production runs the same design decision can be repeated thousands of times. As a result, seemingly small optimisations can have a meaningful impact on material consumption, product weight, logistics and overall cost.

At the same time, factors such as material provenance, recycled content and CO₂e data are becoming increasingly important in material selection. This is driven not only by sustainability objectives, but also by growing information requirements across the supply chain and developments such as CBAM.

The greatest design freedom exists before the die is made

Many of these considerations come together before the extrusion die is manufactured.

When a profile has been fully designed before an extrusion feasibility assessment takes place, it may prove to be perfectly manufacturable. However, it may also mean that opportunities to further optimise wall thicknesses, tolerances, functions or connections are no longer available because surrounding components have already been designed around the existing geometry.

Early technical alignment does not mean that an existing design should automatically be changed. In some cases, the assessment simply confirms that the chosen solution is the right one. In others, a relatively small modification can affect material consumption, extrudability, secondary processing, assembly or repeatability.

Elke Tabak-Keller, Senior Account Manager, BOAL Extrusion Netherlands said "The interesting question is not simply whether a profile can be extruded, but above all what it needs to do within the greenhouse system. If that discussion takes place early enough, all parties can evaluate where material is technically required, which tolerances are genuinely critical and whether functions can be integrated more intelligently. Sometimes this leads to an adjustment, and sometimes it confirms that the original design is already the right solution. Both outcomes are valuable."

From profile drawing to system performance

The value of custom aluminium therefore extends beyond the freedom to manufacture a specific cross-section. What makes custom solutions truly relevant is the ability to tailor geometry, alloy selection, material distribution, tolerances, connections and any secondary operations to the function the profile must fulfil within the greenhouse system.

For greenhouse builders and suppliers of horticultural technology, the most important question is therefore not only about the profile itself. The real question is what that profile must contribute to the performance of the complete system.

For more information

BOAL Extrusion

Tel.: +31 (0)174 527 200

[email protected]

www.boalextrusion.com