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Waterproof and tight: Plumbing sealant

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Keeping seals tight and waterproof is essential — from bathroom and plumbing applications to aquariums. Plumbing sealants prevent water damage and help keep fixtures, sinks, and faucets working for a long time. Here’s the basics on how to use plumbing silicone sealants for powerful, lasting seals.

What are plumbing silicone sealants?

Silicone sealants are a form of liquid adhesive commonly used in building, bonding, and repairing many materials, including finishing joints and filling seams or other gaps. Since they are waterproof and offer durable elasticity and stability in both high and low temperatures, silicone sealants work particularly well as plumbing sealants.

Plumbing silicone sealants are typically available in tubes and cartridges. Because of their many practical uses and easy, tidy application, silicone sealants can be a good alternative to putty for sealing bonds around plumbing fixtures. Other uses include the undersides of sink strainers or pop-up drain fittings for sinks and tubs.

Applying a plumbing silicone sealant

Applying plumbing silicone sealant is an easy process, but doing it properly is critical to ensure a durable, waterproof seal.

Clean the surface. Make sure that the surface is completely clean and dry. Any dust, dirt, or particles can potentially cause a weaker seal.

Using the sealant cartridge. Load the cartridge into a sealant gun. Use a hobby knife to cut off the cartridge seal and open the applicator nozzle, just enough to allow a narrow line of sealant. Pull the handle to fill the nozzle with sealant.

Apply the sealant. Hold the gun at a 45-degree angle. Squeeze the trigger carefully to create an even, steady flow of sealant, dragging the tube nozzle slowly along the target seam. For an even seal, wet your finger with soapy water and spread the applied sealant evenly along the seam, clearing away any excess or residue as you go.

Curing. Silicone sealants must cure before achieving full bond strength. Curing silicone doesn’t require any special steps, just a bit of patience. Curing can take from 24 hours to several days (check your product’s instructions).

Plumbing sealant: Choosing the right product

For household applications requiring waterproof plumbing sealants, silicone sealants offer many advantages over other products, such as acrylic, rubber, or teflon sealants. There are various types of silicone sealants available, and while all offer the same general adhesive properties, some sealants are formulated for specific applications. The composition of the sealant determines how elastic it is, what materials it works best with, and how quickly it hardens.

For use in the bathroom or other wet areas, the best choice is a mold-resistant sealant. This will prevent deterioration and blackening of the joint as it is exposed to moisture over time.

Acidic components in some adhesives may lead to oxidation on some target surfaces, such as mirrors, stone, and marble tiles, aluminum or copper. If this is a concern, choose an acid-free sealant. Again, check your product information to confirm.

For most general purposes, look for a universal sealant, such as Loctite Clear Silicone waterproof sealant. It’s a powerful waterproof plumbing silicone sealant, perfect for use with metal, glass, rubber, tile, and porcelain. Useful both indoors and outdoors, its flexible and impact- and temperature-resistant formula make it ideal for almost all plumbing applications.

Products used

  • packshot front us loctite 079340689299 Loctite Clear Silicone Card_ update 2020
    Loctite Clear Silicone

    Sealing sinks, tubs, plumbing, windows and aquariums. Water and weatherproof.

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