Plumber's Putty vs. Silicone

Standing in the plumbing aisle staring at putty, silicone, tape, and caulk? Here’s the short version. Plumber’s putty is a soft sealing compound used on non-pressurized plumbing fixtures like sink drains, basket strainers, faucet bases, and shower drains. It stays pliable instead of hardening, so it seals well, allows adjustment, and comes apart cleanly later.

Silicone is the other half of the decision. Silicone sealant is a polymer-based liquid that cures into a flexible, rubber-like seal. The rule that solves most jobs: putty for compression seals you may need to service down the road, silicone for permanent waterproof bonds, stone surfaces, and plastics.

Get it wrong and you can end up with stains on a granite countertop, a leaking sink drain, or a permanent mess that’s a pain to remove. Use the right one and you get a tidy, water-tight seal that lasts years and is easy to service when you need it.

When to Reach for Putty, When to Reach for Silicone

Putty works by pressure, not glue. Silicone bonds. Putty compresses. Those are different jobs. That distinction drives the whole decision.

Putty is the classic call for fixtures you might pull apart later. Plumber’s putty is the classic choice for sealing sink strainers, basket drains, and many faucet bases where a compressive, non-adhesive seal is required and you may need to remove the fixture in the future. Because it doesn’t set or glue things in place, you can tighten, re-seat or remove fixtures without chipping or scraping hardened caulk.

It has limits. Plumber’s putty is water-resistant, not fully waterproof in constant-immersion situations. It’s intended for static compression seals rather than joints that need flexible adhesive bonding.

Silicone covers what putty can’t. 100% silicone (kitchen & bath) is best for wet areas; waterproof and mildew-resistant. Reach for it on plastic drains, engineered stone countertops, acrylic tubs. Use silicone when you need permanent waterproofing, adhesion, or flexibility — for tub-to-wall seams, shower corners, undermount sink perimeters (especially with stone), and for any plastic drain / gasket connections.

The trade-off with silicone is time and removal. It comes out of the tube as a liquid and cures to form a hardened, rubbery seal. Silicone generally takes about 24 hours to dry completely. And once it’s set, it bonds and must be cut or dissolved with removers.

Property	Plumber’s Putty	Silicone Sealant
Type	Pliable, non-adhesive compound	Adhesive-based sealant
Best uses	Strainers, faucets, drains, tub waste fittings	Wet areas, stone, plastics, exterior joints
Cure time	None — stays pliable if sealed from air	Cures in hours up to a day
Flexibility	Stays soft but static	Handles up to ~50% movement
Waterproofing	Good for static compression seals	Permanent waterproofing
Removability	Easy before air exposure	Difficult once cured

What Plumber’s Putty Is and Where It Belongs

Composed of a combination of mineral fillers, linseed oil, and other binders, plumber’s putty is known for its flexibility and ease of use. It doesn’t dry hard. It does not cure hard. That is the whole reason it still earns space on a service truck. Under a basket strainer, pop-up drain flange, or some faucet bases, you want a seal that compresses evenly when the hardware gets tightened, then comes apart later without a fight.

The right jobs are specific. Putty is used for sink basket strainers, faucet bases, pop-up drains, and shower drains. On a kitchen strainer, for instance, you roll it into a rope, seat it under the strainer flange, drop the strainer into the sink opening, and tighten the hardware below. What the putty is sealing here is the contact point between the metal flange and the sink basin. That’s a flat, compressed joint, which is exactly where putty does its best work.

Just as important is knowing where it doesn’t belong. It is not an adhesive or glue. Thus, it should not be used in any pressurized connection, such as a gasketed fitting or on the thread of pipes. For those, use thread sealant or Teflon tape.

Skip it on toilets, too. Historically, plumber’s putty was used to seal a leaky toilet or toilet bowl to a finished floor. However, this product can’t support the weight of a toilet and is not waterproof. And it offers nothing for windows or doors — plumber’s putty does not have any insulating qualities; and therefore, is not the right choice for sealing windows or doors.

Shelf life matters if you want to reuse what’s in the can. Oatey Plumber’s Putty will last two years from the manufacture date if the lid is sealed properly.

Western Building Center carries plumber’s putty in a range of sizes — a 7 oz, a 9 oz oil-free, a 14 oz, and a 3/4-inch by 54-inch roll among them — plus thread seal tape and pipe thread sealants for the pressurized joints putty can’t handle.

Surface Compatibility — The Mistake That Stains Counters

This is where most DIY jobs go sideways. A lot of bad putty jobs start the same way. Someone swaps a faucet, lays down standard plumber’s putty under the base, tightens it up, and later notices a dark ring in the counter that was not there before.

The cause is the oil. Because plumber’s putty is oil-based, it can stain porous materials, such as granite, marble, quartz and sandstone. The big offenders: granite, marble, quartz, and Corian® are the big problem materials. On those tops, standard putty can leave staining or discoloration.

The fix is stain-free putty. Oatey and Hercules offer a stain-free plumbers putty for natural surface materials found in sinks, countertops, strainers and shower bases including granite, marble, quartz, sandstone and Corian®. It’s oil-free and will not stain the porous material.

Plastics are a different problem entirely, and stain-free putty does not solve it. Stain free putty should not be used on ABS materials. Instead, silicone sealant is recommended. Same goes for acrylic. Plumber’s putties could have an adverse effect on the acrylic finish similar to the same effect on ABS materials. You should only use 100% silicone for this application. Put plainly: plumber’s putty should not be used on plastics (PVC or ABS) because it will affect the integrity of the material and lead to product failure.

For the porous-surface stock, Western Building Center carries a 9 oz oil-free plumber’s putty.

Installation Basics for a Leak-Free Seal

A proper putty seal is simple, but the steps matter. Start clean. Before using plumber’s putty, ensure all surfaces are dry and free from hardened putty, dirt, wax, oil, and grease. Remove debris by wiping it with a cloth, scraper, or wire brush as needed, and dry the surface.

Then shape and seat it:

1. Knead the putty in your hands until soft and pliable. Then form it into a rope or a long, cord-like shape (roughly ½-inch thick).
2. Form a complete circle with the putty around the underside of the flange of the item you are installing, making sure to blend the two ends where they meet. If the rope is too short, start over and roll a longer one.
3. As you secure your product, the excess putty will ooze out from under the flange and around the fixture, ensuring sufficient putty has been applied and a continuous seal has been made. Don’t overtighten fixtures; the goal is a snug, sealed fit, not crushed putty.
4. After the item is secured, wipe away excess putty with a putty knife. If the excess putty is clean and debris-free, it can be put back in the container.

Cold matters here — and in Montana garages and basements, it matters often. If putty is used in colder applications, wait 10 minutes after the initial installation and confirm the product does not need an extra turn to ensure it is properly secure.

Then test it. The sink, faucet or shower can be used immediately after the part has been put into place. Run the water after installation to check for any leaks. If a leak is present, the drain will have to be removed from the fixture before reapplying putty.

One storage note that earns its keep in dry winter air: seal the lid completely so the putty stays clean and isn’t exposed to air. If exposed to air for an extended period, putty can dry out and cannot be reused.

Frequently Asked Questions

When should you not use plumber’s putty? Most plumber’s putty is oil-based, meaning it will stain porous surfaces like stone and porcelain. It can also degrade fixtures made of plastics (like acrylic and ABS) and cause failure. And because it isn’t an adhesive, plumber’s putty isn’t suitable for pressurized connections.

Can you use silicone on a sink drain? Yes, silicone sealants are safe for use on sink drains. However, silicone takes about 24 hours to dry completely. So, don’t expose the seal to moisture until it has finished curing.

Should I use plumber’s putty or silicone on a shower drain? Plumber’s putty is suitable for shower drains in most cases. However, if you have an acrylic or ABS shower, you should use a silicone sealant, as plumber’s putty can damage plastics.

Does plumber’s putty cure or harden? No. Once out of the container and used as a bedding compound for strainers, faucets and tub waste and overflows, the putty will remain pliable when it is not exposed to air. If the putty is exposed to air for an extended period of time, it will harden and become brittle.

Can hardened putty be brought back to life? No. Once the putty has dried there is nothing that can be added to regenerate the putty without affecting the quality of the product. The lesson: keep the lid sealed.

What’s the difference between stain-free and regular putty? Stain-Free Putty is an oil-free non-staining putty that performs the same as other putties but can be used safely without staining granite, marble, quartz, sandstone, Corian®, or any natural, porous surfaces.