How to Measure and Specify a Custom Strip Drain

Ordering a custom drain is straightforward when you know what to measure and what to decide before you get in touch. Get the specification right and the drain arrives ready to install, made to the millimetre for your project. Get it wrong and you're working around a product that doesn't quite fit.

This guide walks through how to measure and specify a custom strip drain, covering length, width, depth, outlet position, grate style, and material, whether the drain is for a pool surround, a driveway, a shower, or a commercial site.

When a custom drain is the right call

Standard drain lengths suit standard situations. The moment your project has a fixed dimension that the drain needs to match, a pool coping run, a driveway width, a door opening, a shower recess between two walls, custom is the correct answer rather than a compromise.

Joining multiple short standard drains end to end to make up a length looks poor, creates leak points, and complicates the install. A single drain manufactured to the exact length is cleaner, faster to install, and more reliable. Custom strip drains can be manufactured as a single piece up to 3640mm, with longer runs handled by joined sections aligned on site.

Measurement 1: Length

Measure the full run the drain needs to cover, in millimetres. For a shower, this is usually wall to wall. For a pool, the length of the coping edge you're draining. For a driveway, the width of the driveway at the collection point. For a threshold, the full width of the door opening.

Measure at the finished surface level, and measure twice. If the drain sits between two fixed surfaces, like walls in a shower, tell us that when you order. A wall to wall drain is made slightly under the measured dimension to allow for install, and we handle that allowance for you.

Measurement 2: Width

Channel width is partly practical, partly aesthetic. Wider channels move more water and suit high flow situations like driveways and pool surrounds. Narrower channels suit showers and thresholds where flows are lower and a finer line looks better.

As a starting point: 100mm wide suits most shower and bathroom applications, and wider channels come into play for driveways, pools, and commercial areas where volume is higher. If you're not sure, tell us the application and we'll recommend the width.

Measurement 3: Depth and the substrate

The drain needs to fit the depth available in the slab or screed. In a retrofit or a slab with limited set down, depth can be the constraint that shapes the whole specification, so check what you have before deciding anything else.

Also worth confirming early: what the drain is sitting in. A drain cast into a new concrete pour is detailed differently to one set into a screed over a membrane. If there's a waterproofing membrane, the drain needs the right flange detail for the membrane to dress into.

Measurement 4: Outlet position and size

This is the specification that catches people out. The outlet needs to line up with your plumbing, and on a custom drain you choose where it goes: centre, offset to one end, or at a specific measurement along the channel.

Measure from one end of the drain run to the centre of the existing or planned waste pipe, and note the pipe size. Horizontal or vertical outlet orientation matters too, a vertical outlet drops straight down into the waste, a horizontal outlet suits shallow installations where there's no depth for a vertical drop.

Another consideration is whether the drain requires or would benefit from a fall to outlet (F2O) for efficient water flow to the outlet. 

Choice 1: Grate style

Two grate styles cover most projects.

Wedge wire is a stainless steel bar grate with consistent slots. It handles high flow, cleans easily, provides slip resistance underfoot, and gives a defined linear look. It's the usual choice for pool surrounds, driveways, and outdoor areas.

Tile insert has a recessed tray that takes a cut piece of the surrounding tile or stone, so the drain all but disappears into the floor. It's the pick for bathrooms and any area where a seamless finish matters. For a warmer metal finish, tile insert drains are also available in solid brass, not coated steel, solid brass throughout.

Choice 2: Material

For outdoor, pool, and coastal applications, the specification is 316L marine grade stainless steel. The L grade has better corrosion resistance at weld points, which is exactly where cheaper drains fail. Chlorine, salt air, and constant moisture will find out a 304 grade drain within a few years.

Every Strip Drains product is fabricated with metal components throughout, channel, grate, outlet, and end caps. No plastic fittings anywhere in the drain.

What to send us for a quote

You don't need a formal drawing, though we'll happily work from one. For most projects, this is enough:

• Length of the run in millimetres, and whether it's between fixed surfaces
• The application: shower, pool, driveway, threshold, commercial
• Outlet position measured from one end, and the waste pipe size
• Available depth, and whether there's a membrane
• Grate preference: wedge wire, tile insert, or brass tile insert

A sketch on paper with measurements photographed on your phone does the job. From that, we can confirm the specification, flag anything that needs a decision, and quote the drain.

Made in Sydney, to your measurements

Every custom drain is manufactured in our workshop in Caringbah, Sydney, and we've fabricated drains for everything from single bathroom renovations to full apartment developments and commercial forecourts. Because we make them here, lead times are short and we can talk through the detail directly with your builder or plumber if anything needs clarifying.

If you've got a project that needs a drain made to size, send us your measurements or fill in an order form, and we'll take it from there.