Choose under-sink storage only after mapping the plumbing and the space needed to access it. Cabinet width alone will not establish fit. The sink bowl, waste fittings, hoses and valves can all occupy space above or behind an organiser, and a moving unit needs clearance throughout its full travel.
Draw the space in three dimensions
Start with a front-facing sketch of the cabinet interior. Record internal width, depth and height, then mark the sink bowl and every visible service. Add a side view if the waste projects forward or the bowl hangs low into the cabinet.
Measure the locations of obstacles from fixed cabinet surfaces, not only the gaps between them. That gives your installer a clearer picture of where a proposed tray or bin will sit. Include hinges and door-opening restrictions as well as plumbing.
Photographs are useful, but perspective can hide depth. Pair them with written dimensions and identify anything you could not measure reliably. Leave uncertain measurements for the installer or plumber rather than treating an estimate as a clearance.
Preserve access to services
Storage should not block shut-off valves, trap access or the ability to inspect connections. Flexible hoses should not be compressed, stretched or rubbed by a drawer. Do not move or alter plumbing to suit an organiser without an appropriately qualified tradesperson assessing the work.
Consider how the storage will be removed if a repair is needed. A neatly packed cupboard can become difficult to service when every item must be dismantled first. Ask the installer to explain the intended access arrangement before the layout is finalised.
Check closed fit and moving fit
For a pull-out unit, trace the full opening path. Check the rear of the assembly, the top of its contents and any moving lid. Then allow for lifting containers out. The closed position is only one stage of normal use.
Also consider what you plan to store. Tall bottles may extend beyond a tray's stated height, and a bin needs space for waste and removal. Do not use the organiser's empty dimensions as a substitute for the complete loaded arrangement.
Read under-sink product specifications carefully
The Imperial 50L under-sink bin system for an 800mm cabinet lists an adjustable width of 700–740mm, depth of 423–490mm and height of 270mm. It includes three bins, lids and a mounting tray; runners are not included.
Its description identifies a Blum TANDEMBOX drawer-system application and states that load capacity depends on the runner system. Confirm the exact compatible components and your cabinet's available space. The term “under-sink” identifies an intended application, not a guarantee that every plumbing arrangement will clear it.
For purpose-designed vanity drawers, the ONDA plastic pipe cut-out insert lists a 150mm × 235mm cut-out, suitability for a 16mm base and M-height drawers. It is a component to evaluate within a drawer design, not permission to cut an existing drawer without assessing its construction.
A practical clearance record
- Actual internal cabinet dimensions and clear opening.
- Sink-bowl depth and position.
- Waste, trap, hose and valve locations.
- Required service-access areas confirmed by the tradesperson.
- Full organiser travel and container-removal clearance.
- Exact drawer, runner and mounting components required.
Choose a layout that stays manageable
Review the under-sink storage collection with your measured plan, not just the cabinet width. Keep cleaning products in their original labelled containers and follow their storage instructions, including requirements concerning children and separation from other items.
If the space is complicated, contact Imperial Glass & Timber with the sketch and photographs before ordering. Resolving one awkward pipe or inaccessible valve at the planning stage is much easier than discovering the conflict after the storage system arrives.