What a fabricator should ask of an aluminium door panel supplier

A fabricator should expect five things from an aluminium door panel supplier: proven compatibility with the profile system they use, a panel that is flat and stays stable over time, good quality powder coating with a colour that matches the windows, factory machining to an approved drawing, and lead times that fit the job. Everything else is brochure.

This guide covers each of these points and the questions to ask before placing a first order.

Will the panel fit your profile system?

The door panel has to work with the fabricator's profile system. There are two main cases:

• Infill panel, fitted inside the door leaf like a sealed glazing unit and held by glazing beads. Its thickness has to match the space available in the profile.
• Monobloc panel, bonded over the leaf on both faces so the frame profile is hidden and the door has a flush look from outside. Here the panel is designed to suit the specific leaf and system.

Before ordering, confirm:

• overall panel thickness and tolerance;
• profile system and series;
• opening direction (left-hand or right-hand) and hinge side;
• exact leaf dimensions, not the opening size.

A serious supplier asks for this information before quoting. If they don't ask, the question will come up later, in the workshop.

Will the panel stay flat?

The most expensive fault in a door panel is bowing. A door that does not close properly or lets air through always comes back to the fabricator, even when the panel is to blame.

What to ask

• What the panel core is and how the skins are bonded.
• What sheet thickness is used on each face.
• Whether there is internal reinforcement in the lock, handle and hinge areas.
• What precautions they recommend for doors on elevations that get a lot of sun.

Dark colours

Dark colours absorb more heat. On a door in the sun, the outer face gets much hotter than the inner face and the two faces expand at different rates. The supplier should be able to explain how the panel and the leaf cope with this. If the answer is vague, ask for references for dark doors already installed.

Powder coating and colour matching

Coating quality

The panel will be exposed to sun, rain and, in many coastal areas, salt air. Ask:

• whether it is powder coated and what pretreatment the aluminium receives;
• what coating thickness is applied;
• whether the powder coater holds a quality certification and which one, and ask for the current certificate.

Colour matching

The panel colour has to match the windows and the frames. Always state:

• the full RAL reference;
• the gloss level (matt, satin or gloss);
• the texture, where there is one;
• whether it needs to match windows already installed, in which case send a sample.

For wood-effect finishes, ask for the exact pattern reference and, if possible, a physical sample. Woodgrain patterns vary between film and sublimation suppliers.

Factory machining and cut-outs

Locks, cylinders, pull handles, vision panels, glazing and stainless steel details all need accurate drilling and cut-outs. Done in the workshop, they raise the risk of chipping the coating or misaligning the groove pattern.

Ask the supplier for:

• a technical drawing of the panel with dimensions for all machining;
• drawing approval before production;
• confirmation of the intended hardware (make and model), so the cut-outs match.

Technical documentation and CE marking

In the European Union, external pedestrian doors are covered by the product standard EN 14351-1 (published in the UK as BS EN 14351-1) and need a declaration of performance and CE marking. Responsibility lies with whoever places the door on the market, which in many cases is the fabricator who makes up and installs the door.

So ask the panel supplier for the technical data you need for your documentation, for example the panel's characteristics and thermal performance information where available. Be wary of figures given without saying which door configuration they refer to.

Lead times, packaging and service

Lead times

Ask for lead times on standard colours and on special colours, and whether the lead time runs from the order or from drawing approval. On a build, the front door is often one of the last items to arrive, and a delay there holds up handover of the house.

Packaging

A powder-coated panel scratched in transit is a lost panel. Check how panels are protected, especially if they are coming from another country.

Technical contact

When a question about sizes or hardware comes up, the fabricator needs someone on the other end who understands doors. Ask who that person is and how to reach them.

Quick checklist before your first order

• Did the supplier ask for the profile system and thickness?
• Did they send a technical drawing with machining for approval?
• Did they explain the core, skins and reinforcement?
• Did they say how they guarantee colour and gloss?
• Did they give clear lead times for standard and special colours?
• Is there a named technical contact?

How we work with fabricators

Portancora has been manufacturing aluminium panels for entrance doors for 25 years: flush, grooved, glazed and stainless steel, as well as complete monobloc and pivot doors. We powder coat in any RAL colour and produce wood-effect finishes. A large part of our work is for fabricators and window and door companies in Portugal, Galicia and other European markets.

To show your customer how the door will look, you can use the door visualiser. To ask about trade terms, technical drawings or a quote, contact us.