Aluminium Door Buying Guide: How to Choose the Right Door

Handing and opening direction: the decision that cannot be undone

Of everything in this aluminium door buying guide, handing is the item most often settled too late. A hinged or pivot door has to be built to open a specific way: inward or outward, hinged left or right. That decision determines which side the hinges sit, which side the handle and lock sit, and how the frame is assembled — and it cannot be swapped after manufacture.

Work it out by standing outside the opening, looking in. Decide whether the leaf should swing towards you or away, and which side it should hinge on so that it opens against a wall rather than into circulation space. Check the arc against furniture, steps, a boundary wall and any outward-opening window on the same elevation. On a patio, check it against the table.

Thresholds, drainage and where doors actually leak

Doors leak at the bottom far more often than at the top. The threshold has to do two jobs at once: let people cross it comfortably and shed water away from the building. A sliding door track sits proud of, or recessed into, the finished floor, and how that junction is detailed decides whether driven rain runs outside or inside.

Agree the threshold detail and the finished floor level before the frame is fitted, not after. Keep the drainage path clear — blocked weep holes trap water in the frame, and trapped water is what damages seals, stains finishes and eventually reaches the glazing line. On an exposed elevation this matters more than any other single detail.

Hardware, locking and security: aluminium door buying guide

The frame usually outlives its moving parts. Handles, hinges, rollers, stays and gaskets wear long before the aluminium does, so hardware quality is where a door earns or loses its reputation. On an exposed or coastal site, stainless fixings are worth specifying up front, because replacing them later means dismantling a leaf that is already installed.

Security on a glazed door comes from the whole assembly rather than the lock alone: the locking points, the frame fixing into the structure, and the glass itself. Coetz™ glazes as standard with 6.38 mm clear laminated safety glass, which holds together on impact because the interlayer retains the fragments — a meaningful difference on a ground-floor door.

Measuring: what to send and what to check: aluminium door buying guide

Measure the structural brick opening, not an existing frame. Take the width at the top, middle and bottom and the height at the left, centre and right, then work from the smallest figure in each direction. Check both diagonals for square. Coetz™ frames are manufactured 10 mm under the catalogue size in each direction to give fitting clearance, so the opening should be measured as it is, not as it was drawn.

For a replacement, measure once the old frame is out. Old steel frames are commonly built into the masonry and packed out, so measuring the frame simply repeats somebody else’s error. Our step-by-step guide to measuring aluminium doors covers the sequence in more detail.

Coordinating supply with your installer

Coetz™ supplies aluminium doors; installation is arranged by your own builder, contractor or installer. That split works well provided the responsibilities are clear. The supplier is accountable for manufacturing to the confirmed dimensions and specification; the installer is accountable for how the unit is packed, fixed, sealed and made weathertight. Agree who signs off the completed opening before work starts.

Give your installer the lead time — 1–2 days from order — and confirm access and lifting arrangements for the larger units. A 2.7 m sliding door is a two-person lift at minimum and must be moved upright, never flat.

Compliance and when to ask a professional

Glazing in and around doors carries safety requirements, and large or unusual glazed assemblies can raise structural questions that a catalogue cannot answer. Where a decision has safety or regulatory consequences, work from the current published standards issued by the South African Bureau of Standards and have the specification confirmed by a suitably qualified person for your project.

Where to go next

Browse the Coetz™ aluminium doors range to compare configurations and sizes, or search the shop by size if you already know your dimensions. If you are weighing aluminium against other materials, the aluminium versus timber and aluminium versus uPVC comparisons set out where each genuinely wins.