Knowledge base · Technical note
Disc lock or cylinder lock? Choosing by door type
Most self-storage hardware mistakes are made before the order — the wrong family was chosen for the door. Here is how the decision actually works.
Start with the door, not the lock
The lock does not define the specification; the door does. Three questions settle it:
- Is there a hasp or padlock eye already on the door, or a cut-out for a cylinder?
- Does the tenant key the unit themselves, or does the facility issue the lock?
- Is the door exposed to weather, or inside a covered corridor?
The answers point to one family. Choosing by product photo instead is how facilities end up with hardware that does not fit and a maintenance backlog.
Unit door with a hasp — disc or combination padlock
This is the common case. The door already has a hasp, so the lock has to resist cutting rather than disassembly. A disc padlock protects the shackle inside a hardened body, which makes it far harder to attack with bolt cutters than a standard padlock.
Choose a combination padlock instead when you do not want to issue keys at all — for short-term or self-service units. The trade-off is that a forgotten code is a support call, where a lost key is a replacement sale.
Unit or corridor door with a cylinder — cylinder lock
If the door has a cam or mortise cut-out, you need a cylinder. This is also the family that lets you standardise: replacing mixed cylinders with one model is what makes a key plan possible at all.
Cylinder size is the parameter that decides fit. Measure across the cylinder face, or send a photo with a ruler — that is usually enough for us to identify it.
Roll-up door — latch and hasp
Roll-up doors do not take a padlock directly in most cases; they take a latch and hasp assembly, sometimes with a slide bolt. This is the family where a millimetre of mounting-hole pattern decides whether the part fits, so we work from a photo of the existing part or the door manufacturer's drawing.
Vacant and delinquent units — overlock hardware
A separate job with separate hardware. An overlock plate or lockout bracket has to clear the lock body and the door track through the full swing, which is why it is verified against a sample door rather than a drawing.
How to confirm before you commit
Send the door type, the cylinder size or mounting dimensions, or a photo. We confirm fit with a physical sample before you commit to a quantity — fit confirmed by sample, not by drawing.
Confirm it on your own doors
Send a door photo, the cylinder size or the mounting dimensions. We confirm fit with a physical sample before you commit to a quantity.
What readers ask next
Once the door type is agreed, buyers usually ask these.
Can you send one of each to compare on our own doors?
Yes. Comparing both families on the actual door settles the decision faster than any catalogue does, and sample lead time begins at five days. Tell us which door types to cover.
Can both families be ordered in one batch?
Yes, they can be supplied together and packed by door type. It also keeps both lines on one keying plan if a single key is to serve the site.
If we choose the wrong family, how expensive is the fix?
A wrong family is not repairable on site because the door decides the fit. That is why the comparison happens on a sample before the bulk order, and why we ask for a door photo before quoting.