How to measure a bin
The designer sizes the rack from the bin, not from a generic shelf opening. Measure the bin the way it will sit in the rack: lip up, sliding in from the front. All inputs are inches.
A catalog size is a starting point. Bins from the same product line are not identical, a lid changes the height, and a printed “30.4 in” is not a promise about the tote in your garage. If you own the bin, the tape measure wins. Presets and how they differ from the printed size are on the 27 gallon, Iris, and Brightroom pages.
Before you measure
- Empty the bin so the sides are not bowed by the contents.
- Decide whether you store it with the lid on. If you do, measure height with the lid on. The lip that sits on the wood is still the bin’s lip, not the lid’s latch, unless the latch is what would hit a rail.
- Measure outside dimensions. The rack has to clear the outside of the bin.
- Measure both directions and use the larger one when the bin is a little out of square.
The fields, in order
Bin depth
Front to back, outside, along the direction the bin slides into the rack. This drives the outer depth of the whole rack. The uprights sit at the sides of each bay, so the bin is not trapped between a front post and a back post. The rack is made as deep as the bin, plus any depth slack.
Depth slack
Extra depth beyond the bin, split evenly in front of the bin and behind it so the bin stays centered. Use a little when you want the bin to sit shy of the front face, or when the lid handle needs room. Zero means the rack depth equals the bin depth.
Bin width
Left to right at the widest point. On these bins that is the lip, the rim that sticks out at the top. Do not measure down at the floor of the bin. The body is narrower there, and using that number as the width will make the bay too tight for the lip.
Lipless width
The width of the body just below the lip, where the wall steps in. This is the part that has to pass between the inner edges of the two cleats. Bin width minus lipless width is the total lip overhang, left and right combined. Half of that, minus any bin-cleat slack, is about how much of each lip actually bears on a cleat.
On a preset, lipless width starts locked to bin width minus the overhang we use for that bin (2.75 in on the 27 gallon tote, 0.75 in on the Iris and Brightroom presets). Unlock it if your tape disagrees. If you are not on a preset, measure it yourself. The form will not invent a lip.
Bin height
Overall outside height, from the bottom of the bin to the top of the rim (or the top of the lid, if that is how you measured). This stacks with vertical slack to set how far apart the rows are.
Height above lip
From the lip seat up to the top of the bin. The lip seat is the underside of the lip, the flat that will rest on the wood, not the top of the lid and not the bottom of the bin. Height below the lip is the rest of the height. The form fills that in as bin height minus height above lip, and it is not edited on its own.
Getting this wrong moves the cleat. Too little “above lip” and the cleat sits too high, so the bin bottom collides with the cleat of the row below or the top rim hits the next cleat. Too much, and you waste a gap above every bin.
Vertical slack
Extra space between stacked rows, on top of the bin height. It is air between the top of one bin and the lip seat of the bin above. A little slack lets you lift a bin off the cleats without scraping the row above. A lot of slack makes a taller rack.
Top/bottom slack
Clearance between the lowest bin and the bottom rail, and the same clearance between the highest bin and the top rail. The default is ½ inch at each end. The rails are only 1½ inches tall, because the 2×4 is turned with its narrow face toward you.
Bin-cleat slack and lip-to-upright slack
These two move together.
- Bin-cleat slack is extra room between the two cleats, beyond the lipless body, both sides combined. More slack means the body passes more easily and each lip has less wood under it.
- Lip-to-upright slack is extra room between the outer edges of the lips and the uprights, both sides combined. The lip has to clear the upright as the bin goes in, then sit down on the cleat.
The form shows lip-cleat contact per side after both numbers. That is the bearing length of each lip on its cleat. The tool wants that contact to stay at least half of what you would get with zero bin-cleat slack, and it warns if the lip would run into the upright. If you see that warning, believe it and change the slack before you cut.
Layout and saw
- Bins across is how many bins side by side in a row.
- Bins up is how many bins stacked in a column.
- Kerf is the width of the saw cut the packing math throws away. The default is ⅛ inch. Set it to the blade you will actually use. The same kerf is used when a 2×4 is ripped into two cleat blanks.
A reliable sequence
- Measure depth, width, height, lipless width, and height above the lip.
- Enter them, or pick a preset and unlock anything your tape disagrees with.
- Leave slack at the preset until you have test-fit one bin. Then tighten or open it.
- Set bins across and bins up, and read the outer size against the wall you mean to use.
- Check the warnings under Dimensions before you trust the cut list.
Then read how the rack goes together. The picture only helps if the lip you measured is the lip that lands on the cleat.