The cabinet is labelled 24 inches wide. The space between its hinges is not. Under a sink, the bowl, drain and faucet hose make the available space stranger still. Measure the space the complete system travels through, not the cabinet name.

Check the opening at the narrowest point

Record clear width between the open door and frame, usable depth to the first obstruction, and height beneath the sink or drawer above. Include hinge arms and any door hardware that enters the opening. Photograph the plumbing with a ruler in the frame so a supplier can see what the dimensions refer to.

IKEA Canada: HALLBAR pull-out frame 204.228.53 is one example of a pull-out frame designed around specified compatible bin combinations and cabinet installation. Use the complete system dimensions and instructions, not a bin's volume as a proxy for fit. A 20-litre bin and a 20-litre pull-out assembly are not the same-sized object.

Test all four bin movements

  1. Pull out

    The frame clears the door, hinges and nearby handles.

  2. Open lid

    The lid clears the sink bowl or drawer above.

  3. Lift bin

    The full bin can leave the frame without tipping into plumbing.

  4. Return

    The bag rim and handles do not snag on the way back.

Do not spend the shutoff's space on a larger bin

Leave access to shutoff valves and drain connections. Check the full travel of a pull-down faucet hose, which may descend behind the bin. A hose that rubs every time you sort recycling can turn a storage upgrade into a leak. Keep the appliance's or faucet's required clearances; do not reroute plumbing casually to gain a few centimetres.

A separate cabinet beside the sink may hold bins more efficiently than the sink cabinet itself. A smaller under-sink bin can also be easier to empty and clean than a tall one trapped beneath a drain. Make a cardboard box the size of the proposed bin if the removal path is difficult to picture.

Choose the capacity after checking the routine

List the streams your household actually separates and check your municipality's current accepted materials and bag rules. A large recycling bin and smaller food-scrap container may suit you better than equal bins. Check how the bags fit the rim and whether replacement bins are readily identifiable by model.

Confirm the system's load rating for the intended installation, including full bins, and use the specified fixing method. Keep cleaning access under and behind it. If you see dampness during measuring, trace that water first; an organizer should not conceal a cabinet floor that is already deteriorating.