An aluminum entrance door that has started dragging on the threshold or catching at the top corner is telling you something specific: it has dropped. Not warped, not swollen — dropped. The whole leaf has rotated a couple of millimetres out of square because whatever was carrying its weight has worn out.

On a commercial aluminum door that weight is carried in one of two ways, and knowing which one you have decides whether this is a straightforward part swap or a job that touches the frame.

Pivot or hinge — identify it before anything else

Offset pivot doors

Look at the bottom of the door on the hinge side. If you see a metal arm running from the door bottom into a fitting in the threshold, and the door swings around a point set slightly in from the edge, it is on offset pivots. The entire weight of the door and its glass rests on that bottom pivot.

This is the standard for aluminum storefront entrances because it handles heavy doors and lets the leaf clear the frame cleanly. The trade-off is a single wear point taking all the load.

Centre-hung pivots

The door pivots on a point roughly in the middle of the door thickness, usually with a floor closer buried in the slab underneath. Common on double doors and on entrances with concealed closers. Here the floor closer itself often carries the load, which makes a failure more expensive.

Continuous or butt hinges

A full-height hinge running the length of the leaf, or three to four individual hinges. Load is spread out, so sag is slower and more gradual — but when it does happen, the fix involves the frame side, not a single part.

What the sag pattern tells you

• Catching at the top corner on the latch side, gap opening at the bottom hinge side — classic bottom pivot wear. The door is rotating about its top pivot.
• Dragging evenly across the whole threshold — the door has come straight down. Bottom pivot or floor closer spindle.
• Binding at the hinge side, tight all the way up — frame movement, not door wear. Something has shifted in the opening.
• The gap changes with the weather — thermal movement in a long extrusion, usually tolerable, sometimes fixable with an adjustment rather than a part.
• Corner joint visibly open, stile separating from rail — the door has been running out of square long enough to damage itself. This is past adjustment.

Why it wears out in the first place

Three things kill bottom pivots, and all three are avoidable.

Grit. The pivot sits at floor level right where sand, salt and street dirt collect. That grit gets into the bearing and grinds it. Entrances that get swept at the threshold last noticeably longer than ones that do not.

Water. A threshold that pools instead of draining sits water directly in the pivot fitting. In winter it freezes there.

An over-tightened closer. When the closer is set too strong, every cycle slams the door into the frame and shock-loads the pivot. A closer adjusted so the door latches firmly without slamming will roughly double the life of everything below it.

What the repair involves

If the pivot is worn but the door is still square, this is a good outcome. The leaf comes off, the bottom pivot and top walking beam get replaced, the door goes back and gets shimmed to sit square in the opening, and the closer is re-adjusted. Same-day work in most cases.

If the corner joints have opened, the stiles and rails have to be pulled back into square and re-secured before any new pivot goes in. Installing a new pivot under a racked door just wears the new part out on the same schedule. Proper aluminum door repair addresses the geometry first and the hardware second.

If the floor closer has failed, expect a bigger job — the unit is set in the slab and reaching it can mean cutting floor finish. This is the one failure mode worth catching early, because a leaking or seized floor closer only gets more expensive.

The check that costs nothing

Once a season, stand inside the entrance and look at the gap between the door edge and the frame from top to bottom. It should be even — roughly the thickness of a nickel, all the way up. If the top is visibly wider than the bottom on the latch side, the door has already started to drop, and you are in the window where a pivot swap fixes it completely.

Wait until it drags on the threshold and you are usually into re-squaring as well. On a busy entrance that window is measured in months, which is why commercial door repair on a scheduled basis costs less than the same work done reactively.

When replacement makes more sense

A door that has been racked long enough to deform its extrusions, or one where the frame anchors have loosened in the opening, may not come back to square reliably. At that point the honest comparison is a rebuild against a new leaf — and if the glass is also being replaced, new usually wins. That decision is worth getting a straight opinion on rather than paying for repeated adjustments that never quite hold. Any competent door repair company in Toronto should tell you when a door has passed that point.

Frequently asked questions

Can I adjust the door myself to stop it dragging?

Some pivots have a limited height adjustment, and shimming can buy time. But if the underlying pivot is worn, adjusting it just moves the contact point. You will be back within weeks, and meanwhile the door is still out of square and damaging its own joints.

How long should a bottom pivot last?

On a moderate-traffic entrance, many years. On a high-traffic retail door with grit at the threshold and an aggressive closer, it can be under two. Cycle count and contamination matter far more than age.

Is a sagging door a security problem?

Yes. When the leaf drops, the deadlatch no longer lines up with the keeper, so the throw only partially engages. That is one of the easiest conditions to defeat, and it is invisible unless someone checks the engagement.

Why does the door work fine in the morning and stick by afternoon?

Thermal expansion in a long aluminum extrusion, usually combined with a door that is already marginally out of square. A properly square door has enough clearance to absorb that movement without binding.

Does the closer need to be replaced at the same time?

Not necessarily, but it does need to be re-adjusted after any pivot work — the geometry has changed. If the closer is leaking oil or no longer holds its setting, replace it while the door is already apart.