Door Security Chain & Guard Buying Guide: Fit, Types & RFQ Checklist
A door security chain, concealed chain and swing-bar guard use different mounting geometry and opening limits. Select from the door and frame construction—not only from appearance.
1. Choose the guard type
| Type | How it operates | What to confirm |
|---|---|---|
| Surface security chain | A chain links a door plate and frame plate while allowing a limited opening | Chain length, sleeve, plate positions, opening gap and mounting strength |
| Concealed security chain | The chain or lock body is recessed or partly hidden | Required mortise, body dimensions, edge distance and installation machining |
| Swing-bar door guard | A hinged bar engages a receiver and limits opening | Bar travel, receiver alignment, door/frame offset and release clearance |
| Right-angle or special guard | Guard geometry suits a particular frame or door relationship | Installation orientation, handing, plate angle and approved drawing |
2. Measure the door and frame relationship
Provide a plan view and inside elevation showing door thickness, frame or architrave profile, rebate, available flat mounting areas and opening direction. Measure the offset between the door surface and frame surface. A guard can look correct in a front photo but fail to align when the surfaces sit at different depths.
3. Define the permitted opening
State the required limited-opening gap and where it is measured. Check that the chain or bar can engage and release without striking the frame, handle or nearby trim. If the product is intended for controlled access, hospitality or another regulated use, provide the applicable project requirement; an ordinary product family should not be assumed compliant.
4. Confirm plates, holes and fasteners
Record plate length, width and thickness, hole diameter and centres, countersink, chain/bar connection and operating clearance. Confirm which screws are supplied, but have the installer select fixings for the actual timber, metal, composite or reinforced substrate. Security performance depends on the complete mounting system.
5. Treat printed loads carefully
Some supplier images show printed load options. Record them as supplier-labelled references only unless the test method, fixture, loading direction and report are available. Do not convert a printed value into a certified forced-entry claim.
6. Material, finish and environment
Specify material grade and decorative finish separately. A silver or brushed surface does not prove stainless steel. For exterior, humid or coastal use, describe the exposure and request evidence for the selected plates, chain/bar, pins and screws.
Door-security RFQ checklist
| Application | Residential, hotel, apartment, office or another project; applicable standard if any |
|---|---|
| Door/frame | Material, thickness, rebate, offset, opening direction and inside mounting surfaces |
| Function | Chain, concealed chain, swing bar or special guard; required opening gap |
| Geometry | Plate/body dimensions, chain/bar travel, hole pattern, handing and clearance |
| Finish | Material requirement, finish, environment and matching fasteners |
| Commercial | Quantity per variation, included parts, packing, sample, destination and delivery date |
Common buying mistakes
- Choosing by finish without measuring the door-to-frame offset.
- Assuming a printed load is an independent security certification.
- Ignoring screw withdrawal strength and frame reinforcement.
- Using one chain length or bar geometry for every door profile.
- Failing to confirm handing and inside mounting orientation.
Browse and enquire
Review the door security chains and guards collection, then send an inside door/frame photo and dimensioned sketch with the enquiry.
Prepare a door-security quotation
Send the guard type, door/frame geometry, opening requirement, finish, quantity and destination.