For a toilet that rocks on a sound floor, Sioux Chief 460-11300 stiff polypropylene closet wedges (10 per bag) are the firm, interlocking choice, and Wobble Wedge 5030 is a 30-pack of flexible clear plastic wedges that hide well and trim easily. Shims fix a gap under the base only. They do not fix a leaking wax ring, a broken flange or a soft floor, so check for those first.
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Start with our wobbly toilet guide if the cause is uncertain. This buying guide helps distinguish the shim from the parts that secure and seal the toilet. It does not tell you to cover a leak with caulk or tighten the bolts until the movement disappears.
Toilet shim choices compared
| Exact product | Material and pack | Choose or skip |
|---|---|---|
| Sioux Chief 460-11300 | Stiff polypropylene, 10/bag | Interlocking wedge option; do not drive it forcefully against porcelain |
| Wobble Wedge 5030 | Flexible clear plastic, 30-pack | Trimmable option; confirm the exact material and gap fit |
| Sioux Chief 460-11310 | Soft PVC, 10/bag; dealer option | Different material from the similar-numbered stiff wedge |
| Danco 88523 | Plastic, 6-pack; dealer option | Interlocking design; exact Amazon offer not confirmed |
| Nelson CSH12/42/12/48B | Wood construction shims; dealer example | Use for a maker-approved construction detail, not as the toilet pick here |
STIFF POLYPROPYLENE · TEN SHIMS
Sioux Chief 460-11300: stiff interlocking wedges
Choose it when a stiff purpose-made wedge fits the required base support. The Sioux Chief product table (siouxchief.com) identifies 460-11300 as stiff polypropylene, ten per bag. The linked listing’s title and model field match that part.
The ridges are designed to interlock for stability and stacking. Use that feature to match a suitable gap; it does not establish an unlimited stack height or permission to raise the toilet away from its correct drain connection. If the gap looks substantial, investigate the installation first.
Skip it when the bowl is contacting the flange, the floor is moving or the base leaks. Although the maker describes the stiff material as drivable for general uses, do not interpret that as an instruction to hammer it beneath a fragile toilet. Follow the toilet’s actual installation method.
FLEXIBLE CLEAR PLASTIC · THIRTY SHIMS
Wobble Wedge 5030: flexible clear wedges
Choose it when a flexible clear wedge fits the support area and the toilet instructions permit that approach. The maker identifies its clear standard flexible 30-pack (wobblewedges.com) as SKU 5030 in the public product data. The Amazon model and manufacturer-part fields both read 5030, and the selected offer is sold by Wobble Wedges.
The maker describes moisture-resistant flexible plastic; its material discussion (wobblewedges.com) distinguishes flexible wedges from rigid versions and discusses porcelain applications. Match the exact material rather than treating the brand name as one uniform product.
Skip it if you actually need a rigid shim, another size or a repair beneath the toilet. A larger pack is useful for keeping spare wedges, but quantity should not decide the support material. Do not use a flexible wedge as a way to conceal continued movement after the toilet is secured.
Check the Wobble Wedge 5030 clear flexible 30-pack on Amazon →
Soft PVC and other dealer options
Choose Sioux Chief 460-11310 when you want a softer wedge. Sioux Chief’s product table (siouxchief.com) lists it as a soft PVC closet wedge, 10 per bag, and says soft PVC is easy to trim and resists slipping on tile floors. Some retail descriptions blur those materials, so check the complete part number rather than ordering from “WedgeIt” alone. Skip it if you need the stiff version.
Danco 88523 is another identified plastic wedge. The maker’s six-pack page (danco.com) describes an interlocking design and tells buyers to address a leaking seal before shimming. Skip it as a guessed substitute when the listing or package does not match. We did not verify an exact qualifying Amazon offer for these two dealer options.
Keep the shim choice separate from the brand of toilet. The relevant checks are the fixture instructions, the support contact area, gap and material. A package called universal does not remove the need to inspect those conditions.
Wood shims belong to a different job
Wood construction shims remain useful for work such as doors, windows and cabinets when that installation detail calls for them. The Nelson CSH12/42/12/48B (shims.com) is an exact wood-shim example: its maker identifies the material and construction applications. Select the required length, taper, fastening method and pack for that separate job.
Choose wood for a documented construction use that permits it. Skip ordinary wood scraps beneath the toilet in this guide. We favor the identified plastic toilet-support products above. Wood exposed to water can warp, stain or decay; a hidden leak should be repaired rather than tolerated because the shim is sold as resistant to rot.
Do not assume every brown shim is wood or every composite has the same properties. Check the actual product sheet. A composite or wood construction wedge is not automatically interchangeable with a flexible toilet wedge simply because either can fill a gap.
Check the toilet before shimming
Check for water around the base, damp flooring, odor, visible cracks and movement in the floor. If water is present, stop using the toilet until the cause is established. Our toilet leaking at the base guide separates possible sources; a base shim does not seal the drain connection.
Do not decide that a leak must be the wax ring from one wet spot alone. The supply connection, tank and other sources can wet the same area. Describe when the water appears and have the actual source checked before ordering a repair.
On a new installation, use the toilet manufacturer’s fitting sequence to establish where support is needed. On an existing installation, do not force the bowl sideways or lift it casually to insert a shim. If the seal has been disturbed or the toilet must be removed, plan the appropriate reset and replacement sealing parts.
Fit, trim and finish carefully
Use the shim to fill the support gap without jacking the bowl away from its intended position. The toilet base should have the stable support required by its maker. Do not rely on hold-down bolts to bend the porcelain onto an uneven floor.
The Niagara Stealth installation manual (www.homedepot.com/catalog/pdfImages/53/53a48c94-bd25-4417-b6ba-d686bfa3a808.pdf) provides a manufacturer example of inserting shims beneath a rocking base and warns against overtightening the mounting nuts. Its directions belong to the listed toilets; obtain your own model’s current instructions for the complete sequence.
Trim exposed material using the shim maker’s allowed method. Work carefully around the ceramic, floor finish and supply connection. Do not use the toilet as a cutting board or drag a blade across the floor. Choose another product if the required safe cut cannot be made cleanly.
Complete the base joint as required by the fixture instructions and local code. Caulk is a finishing and sealing material, not a substitute for stable support or a repaired drain seal. Do not copy a universal rule about leaving the back open from an online comment; use the requirements for the actual installation.
When the flange needs attention
A loose or broken flange, incorrect elevation or damaged floor needs its own repair. Oatey’s flange repair guide (oatey.com) distinguishes flange and toilet-support work. A flange spacer changes the drain-connection assembly; a wedge beneath the ceramic base performs a different job.
If the flange sits too high and holds the bowl off the floor, stacking wedges until the wobble stops is not a diagnosis. If it sits too low, wedges do not raise the flange. Our low toilet flange guide explains why the seal and flange elevation need separate attention.
Use a plumber when the flange or subfloor condition is unclear, the toilet leaks or the fixture cannot be supported without a large unexplained gap. Keep the model number and photos of the conditions for the service visit. Do not continue adding shims to a base that still moves or conceals a growing wet area.
Toilet shims FAQ
Should I use plastic or wood toilet shims?
This guide favors identified plastic toilet-support products. Keep wood construction shims for their documented applications; ordinary wood scraps are not our toilet-base recommendation.
Will toilet shims fix a leaking wax ring?
No. Diagnose and repair the leak before treating the base support. A shim does not seal the drain connection.
Can I stack toilet shims?
Use only the product’s permitted interlocking arrangement and a suitable support detail. A large stack is a reason to investigate the floor, flange and fixture fit.
Should I tighten the bolts until the rocking stops?
Do not use the bolts to force a fragile bowl onto an uneven floor. Follow the fixture’s instructions for stable support and mounting, and avoid overtightening.
Are toilet shims the same as flange spacers?
No. A base shim supports the fixture at the floor. A flange spacer changes part of the drain-connection assembly and must be selected for that separate purpose.
How we chose
This is a document-based buying guide, with no claimed hands-on testing. We checked maker identity, materials, package sizes and the linked standard new Amazon offers on October 14, 2026. Both offers had in-stock cart availability; sellers and availability can change. We kept unresolved model variants unlinked. Read our selection method and about Plumbing Picks.
Primary sources
- Sioux Chief 460-11300 (siouxchief.com): stiff polypropylene and ten-shim package.
- Sioux Chief 460-11310 (siouxchief.com): soft PVC distinction.
- Wobble Wedge clear flexible 30-pack (wobblewedges.com): exact product and public SKU 5030.
- Wobble Wedge material discussion (wobblewedges.com): wood/moisture limits and flexible material applications.
- Danco 88523 (danco.com): interlocking wedge and leak-before-shimming guidance.
- Nelson wood-shim product (shims.com): exact wood model and separate construction uses.
- Niagara Stealth manufacturer installation manual, retailer-hosted (www.homedepot.com/catalog/pdfImages/53/53a48c94-bd25-4417-b6ba-d686bfa3a808.pdf): base support and mounting cautions for the named fixtures.
- Oatey flange repair guide (oatey.com): flange condition and repair context.