DIY Help Centre

An interlock is an aluminium extrusion fixed to the locking side of a sliding security door. There are two parts to an interlock system:

1. The frame interlock

The frame interlock is fixed to the non-locking side of your sliding screen door. It acts as a connector, sliding into the corresponding receiving interlock on the fixed glass panel when the door is closed. If you're ordering a SecOnline siding door from our security range, it will come with a frame interlock.

2. The receiving interlock

The receiving interlock is typically attached to the fixed glass panel. It's important to check for an existing receiving interlock when measuring your door, as most setups already have one. See images 1.1, 1.2 and 1.3 for where the receiving interlock is typically positioned and what it looks like. If you do need to purchase receiving interlock, it can be added on to your order via the SecOnline door builder.

There are three common types of receiving interlocks:

• A 3mm interlock

• A 7mm interlock

• And a Flat interlock

No Receiving Interlock?

Most, but not all fixed glass panel frames will have a receiving interlock either attached to or builtin to the aluminium frame; if you find upon inspection that you do not have a receiving interlock, see our interlocks measure guide to determine the type your require.

Option 1. Substitute the frame interlock for a bug seal this will eliminate insects coming from the through the gap between the door and fixed panel - indicate this change when placing your order.

Option 2. Purchase and install a receiving interlock; use the instructions below to ascertain what size receiving interlock you require and then select it from the list of Addons at Step 3 of the Product Builder.

How to select the correct receiving interlock

If you decide to purchase and install a receiving interlocks use the guide below ascertain what size receiving interlock you will require to suit your tracking then select this interlock as an Addon at Step 3 of the Product Builder.

There are three different sized receiving interlocks:

• 3 mm

• 7 mm

• Flat interlock