Bin cage guide: the cheapest enclosure that clears the figure

A large food-grade polypropylene storage tub with a mesh panel cut into the lid clears the 775 square inch published hamster minimum for less than most pet-store cages cost, and takes about an hour. The part people get wrong is ventilation: a tub with a small vent is a humidity trap, and the mesh panel needs to be most of the lid rather than a token square.

This is the honest cheapest answer to hamster housing, and we recommend it knowing it earns us almost nothing. A tub conversion beats every pet-store cage on floor area and on bedding depth, which are the two specifications that matter most.

Choosing the tub

The taper point matters more than any other on that list. Storage tubs are molded to stack, which means the base is always smaller than the rim, sometimes by three inches per side. Take a tape measure to the shop and measure the floor.

The ventilation calculation

This is the part that decides whether the conversion works. A sealed plastic box over ten inches of damp substrate is a humidity trap, and high humidity over damp bedding means mold — which is a genuinely worse problem than a slightly small cage.

1. 1.Cut out most of the lid. Leave a frame of two to three inches around the edge for strength and remove the rest. A token six-inch vent square is not enough, and it is the most common mistake in these builds.
2. 2.Add a side panel too, if the tub is tall. A lid-only vent gives you vertical airflow and no cross-flow. A panel cut high on one long side, above the substrate line, makes a real difference.
3. 3.Use galvanized hardware cloth, quarter-inch or eighth-inch aperture. Quarter-inch holds a Syrian; eighth-inch is the safer choice for a dwarf and is what we would use by default. Not plastic mesh, which gets chewed through.
4. 4.Attach it properly. Sandwich the mesh between the lid and a frame, bolted or riveted, with no gap between the mesh edge and the plastic. A loose mesh edge is both an escape route and something an animal can get caught in.
5. 5.File or cover every cut edge. Cut hardware cloth is sharp, and a chewed galvanized edge is the one scenario where the zinc question in cage materials safety actually matters.

The build, step by step

1. 1.Mark the lid. Draw the panel you intend to remove, leaving a two to three inch frame.
2. 2.Cut it. A rotary tool or a jigsaw with a fine blade; drill a starter hole in a corner. Go slowly — polypropylene melts and grabs a fast blade.
3. 3.Cut the mesh two inches larger than the opening on every side.
4. 4.Sandwich and fix. Mesh over the opening, a second frame of plastic or thin ply over the mesh, then bolts or rivets every three or four inches. Washers on the inside.
5. 5.Deburr everything. Run a file over every cut plastic edge and fold or cover every mesh edge.
6. 6.Wash and dry the tub thoroughly before anything goes in.
7. 7.Fill to ten inches, layered and lightly damped per deep bedding.
8. 8.Add the wheel, hides and food areas, then leave the setup a few hours before the animal moves in.

What a tub conversion is bad at

• It looks like a storage tub. No amount of care changes that. If the enclosure lives in a living room this is the real argument against it, and it is a fair one.
• Scratched plastic clouds. Polypropylene marks, and the view degrades over a couple of years.
• No climbing surface. Same limitation as every solid-walled enclosure.
• Lid security depends on your build. A bought cage has a latch designed by someone. A tub has whatever you fitted, so check it.
• Height for a 12-inch wheel can be tight. A 14-inch tub with ten inches of substrate leaves four inches. Grade the bedding, or use a taller tub.

Two things not to do

Do not stack two tubs with a hole between them. It is a popular build and it creates a fall hazard, a ventilation dead zone in the lower tub, and no additional continuous floor — which is the thing you were trying to add.

Do not use a tub with no mesh at all and prop the lid. A propped lid is not a lid. A hamster that can push a lid will push it, usually at three in the morning.

One closing comparison. A tub conversion typically costs less than a Kaytee CritterTrail Super and gives roughly 780 square inches against that cage's 448, with ten inches of possible substrate against about two. That is the whole argument, and it is the reason this page exists on a site that makes its money from product links.