Can You Use Bathroom Sealant On Windows? (FIVE REASONS)

A window with a hole the size of a pin can permit tremendous moisture and drafts if left unsealed for a long time.

Moisture may ruin the rest of the window or support mold growth.

Drafts, on the other hand, may interfere with the home’s heat efficiency.

The best sealant/caulk should work with your window to stand up to the insults of nature and establish an air-tight seal.

So, Can You Use Bathroom Sealant On Windows?

Here are FIVE REASONS you can use bathroom sealant on windows:

1. Silicone Sealants Improve Your Windows’ Water-resistance Properties

The bathroom and windows have one problem in common: moisture accumulation.

Fortunately, the bathroom silicone sealant holds up well and repels water, two qualities that could solve moisture issues on your windows.

Note: – While there are tons of different sealants, Silicone sealants are water-repellant and preferable for bathrooms, kitchens, and other areas prone to dampness. However, water resistance alone is nothing if mold can still grow around the surface.

So the chemical engineers came up with an enhanced variant of the traditional bathroom Silicone sealant referred to as Sanitary Silicone sealant.

The new variant is “Sanitary” because it contains fungicidal compounds that discourage mold growth.

If you hear about ‘bathroom sealants,’ they are likely referring to Sanitary Silicone sealants, even though traditional Silicone sealant is still relevant today.

See Also: Should Your Windows Be Unlocked And Open After Hours?

For specificity, we will refer to each of the two Silicon variants by their names throughout the article.

Keep your sealant moisture-free during application.

It is easy to think. Silicone sealants repel water in all conditions since they are marketed as water-resistant.

However, these sealants are only moisture-resistant when dry.

Applying it on moist windows or in cold weather will create a weak seal. For that reason, remember to wipe and dry your windows before application.

2. Sanitary Silicone Sealants Protects Windows from Mold

Many homeowners prefer to keep their windows shut in the winter to trap the heat.

The accumulation of moisture over a given period can create all the right conditions for mold growth within the window’s structure.

Fortunately, Sanitary Silicone sealant is water- and mold-resistant. If you still have a few tubes from your last bathroom repair, apply them to your windows for a warm and mold-free winter.

Take good care of your windows.

The effectiveness of the fungicide may decline if you don’t take good care of your windows. Poor ventilation, dirt accumulation, and constant moisture seepage can cause the sealant to fail.

Silicone sealants are mold-proof too.

As mentioned earlier, silicone sealants are waterproof—so the mold won’t readily grow on the surface. Mold needs a moist surface to grow, and that’s a little hard to get on this sealant.

However, it would be best if you opted for Sanitary silicone sealant because it was made for the purpose.

3. Bathroom Sealants Come in Many Colors That Blend with Different Windows

The best thing about silicone sealants is they are sold in multiple colors that blend well with windows. The colors include clear, white, gray, cream, brown and black.

If you are after aesthetically pleasing results, choose a silicone sealant that blends with the décor on your window.

Get your colors right.

Do you trust your eyes when it comes to color selection?

If you don’t, be sure to ask your supplier for the color chart. You should be precise with your color selection because silicone sealants don’t get along with paint.

There will be no corrective painting if you make a mistake. Also, it is worth noting that sealants labeled “clear neutral” are prone to yellowing.

4. Bathroom Sealants Are Generally Solvent-free and Won’t Damage uPVC Windows

The typical silicone sealant contains silicone polymer, a crosslinker, a coupling agent, and a catalyst but no solvent.

The absence of a solvent is good news for your uPVC windows because solvents are known to break down the seal, ultimately disintegrating the unit. You have nothing to worry about if your windows are single-pane.

Wait! What are “uPVC windows?”

Residential windows are split into two: single-pane and double-glazed windows.

While uPVC is an abbreviation for unplasticized polyvinyl chloride (a construction material), it has come to describe double-glazed windows.

Understandably, double-glazed windows are built with uPVC. But solvents and uPVC don’t mix. Fortunately, most silicone sealants are solvent-free, hence uPVC friendly.

5. Bathroom Sealants Are Perfect for Surfaces That Expand/Contract, Such as Windows

Windows expand and contract during the summer. Silicone sealants, on the other hand, are designed to stay elastic and flexible after drying, which supports expansion and contraction.

Better yet, these sealants maintain stability in multiple weather conditions.

Those two features make them appropriate for windows in hot climates. Unlike glue-like window caulk, bathroom sealants are as consistent as gel.

HOWEVER, Bathroom Sealants Are Bad for Your Windows in Terms of Cost-Effectiveness

Here’s why:

Silicone Sealants Are Costlier than Windows Caulk

Bathroom sealants cost more than traditional window caulking materials, which may impact your budget.

But first, let’s distinguish between a sealant and a caulk.

Sealant vs. Caulk

The two terms are used interchangeably but refer to two different construction adhesives. The difference between them is elasticity.

Caulks register a firmer rigidity than sealants, especially after they have dried.

Sealants fill and hold up better than caulking materials, especially in areas prone to great expansion/contraction.

Hence, the perfect caulk for residential windows is a “sealant” rather than a real caulk.

If you must choose between the two, the main factor to consider is the amount of stress acting on the surface they are meant to be applied.

Why Is Bathroom Silicone Sealant Costlier Than Window Caulk?

Silicone sealants are generally expensive because most of them are made from 100% Silicone.

Sanitary silicone sealants are even costlier.

This doesn’t mean Silicone is a rare material, but it has something to do with recent international supply chain disruptions.

The materials used to process Silicone’s raw materials are becoming more challenging to get, driving up the cost of manufacturing.


Just because some sealants are labeled “bathroom” doesn’t mean you can’t use them on your windows.

Frankly, bathroom silicone sealants are far better than conventional caulking materials in terms of moisture resistance and anti-mold properties.

Another advantage is their elastic nature, making them perfect for windows that expand and frequently contract in the summer.

Additionally, bathroom sealants are sold in various colors to blend with your favorite window décor.

They come with a setback though: a high price tag!