No one wants water seeping into the gaps between your bathroom sanitaryware and the floors and walls. Once water begins to enter these hidden gaps, it can wreak havoc, which is why using the best bathroom sealants is crucial when completing your bathroom design.
But, choosing the right sealant is not quite as straightforward as you might think. First, you need to consider whether it is waterproof rather than water-resistant. Does the sealant contain inhibitors to prevent mould from forming? Plus you need to think about colour and whether it can be painted.
There’s a lot to consider when selecting the best bathroom sealants, which is where we can help. Our shortlist of six bathroom sealants is selected to work well in a variety of different scenarios, giving you the scope to find one that works for you.
The quick list
Tight on time? Take a look at this quick overview of all the bathroom sealants in this guide, then head further down the page if you need more detail.
This anti-mould sealant offers durable, consistent protection. Ideal for humid areas, it seals quickly, drying in 20 minutes. It includes a sealant gun and resealable cap.
This anti-mould sealant provides long-lasting protection with a potent fungicide. It dries in stages: skin in 10 minutes, tack-free in an hour, fully dry in 24 hours. It's available in five colours.
This sealant dries quickly, being water-ready in 30 minutes. It's mould-resistant, suitable for all surfaces, and has a lifetime guarantee for cracking and shrinking.
This Dowsil sealant is favoured among plumbers, as it resists mould, combats bacteria including MRSA and E. Coli, and dries within an hour.
Forever Clear’s sealant features a patented Mould Shield preventing mould, mildew, and bacteria growth. Drying within 15 minutes, it contains an anti-bacterial additive and is effective even in high humidity areas.
The 151 Silicone Sealant is ideal for minor bathroom repairs like tiles. While not as durable as others, it's affordable and easy to apply without a gun. Available in two colours and multi-packs.
The best overall bathroom sealant
UniBond’s Anti-Mould Sealant should be a top choice for any household, especially if your main goal is to ensure long-lasting protection. Its high-adhesion formula helps provide a durable result that remains consistent throughout application. Once applied, the sealant forms a permanently flexible and waterproof barrier, reducing the risk of cracks or breakage.
UniBond's anti-mould formula is ideal for use in areas with high humidity, as it quickly seals around baths, toilets, and kitchen sinks. Impressively, it's touch dry in just 20 minutes.
The sealant gun included with the product makes it easy to use, and an integrated resealable cap is convenient for applying small amounts at a time, without worrying about the product drying out.
A versatile all-rounder
This one came really close to taking the title of 'best overall'.
Everbuild's Everflex 500 anti-mould sealant is a great product and performs well across several fronts.
Long-lasting protection? Check. It incorporates a powerful fungicide into the formula, providing long-lasting protection against mould growth.
Dries quickly? Check. A skin will form within 10 minutes after application, then you'll need to wait around an hour for it to be tack free, and roughly 24 hours for it to be completely dry.
Moreover, it is hygiene and sanitary safe – perfect for busy family bathrooms – and is specifically designed to seal and protect areas where maximum hygiene protection is required. It's also available in five different colours.
Fastest drying bathroom sealant
One of the best bathroom sealants for quick drying results. Once applied, the versatile Gorilla All Conditions Sealant is water-resistant in 30 minutes, the fastest water-ready dry time on this list.
This all-purpose, multi-surface sealant is perfect for both indoor and outdoor projects, and you'll be pleased to hear that it prevents mould and mildew from growing. It is also shrink-resistant and crack-proof.
It provides a clear finish, which works especially well on non-white surfaces. But not so good when you need a white or coloured finish to hide gaps around edges. But don’t panic, it's available in white as well, so choose what’s best for your needs.
A small point: it's not paintable, so you will need to look for a decorator's caulk such as this Soudal Decorator Caulk from Amazon.
Tradesperson's choice
This product from Dowsil, formerly known as Dow Corning, has been around for many years, and it remains one of the most popular sealants on the market.
The 785 Sanitary Sealant is a leading product which is particularly popular among plumbers. It utilises a fungicide formula that resists mould to keep your bathroom looking and smelling fresh, and it protects against bacteria growth, MRSA, E. Coli and salmonella.
It dries really quickly too – it should be tack free in under one hour.
The best sealant for clearing mould
The Forever Clear’s patented Mould Shield feature is this sealant's main highlight, as it actively prevents the growth of bacteria, mould and mildew. If you are struggling to keep either of these under control, then this one is well worth a look.
It can be touch dry within 15 minutes of application thanks to its high-quality drying formula, plus it includes an anti-bacterial additive which helps to combat against new germs from cropping up. It's also effective in high humidity areas.
The best sealant for small bathrooms
The 151 Silicone Sealant is a good option for small bathroom jobs, such as repairing tiles, where only a little product will be required. Of course, if you need more than this, you will be relieved to learn that it's also available in a 280ml tube with applicator from Amazon.
While it isn't quite as long-lasting as other sealants on this list, it is affordable, easy to apply, and includes a screw-on applicator nozzle so you don't need a gun for application. It's also available in two different colour options to suit a variety of bathroom design ideas.
How to choose the best bathroom sealant
If you don't use a high-quality bathroom sealant you could be inviting moisture problems that will result in bathroom mould and water damage. When buying a sealant, look out for these essential properties:
Anti-mould
You can trust Homebuilding & Renovating. Our expert reviewers spend hours testing and comparing products and materials in order to help you choose the best for your home and garden. Find out more about how we test.
A moist bathroom environment can be a breeding ground for mould and mildew. To avoid spending hours removing mould from grout, select a sealant that has anti-mould properties to ensure longevity and maintain a healthy space. A good anti-mould sealant not only prevents unsightly black spots but also reduces the risk of health issues associated with mould spores.
Quick drying time
A sealant with a drying time of under an hour is ideal, ensuring a robust, waterproof barrier in a short timeframe. However, it's crucial to differentiate between 'touch dry' and 'fully cured'. While some sealants may feel dry to touch within minutes, they might take longer to fully set and achieve maximum strength. Always check the manufacturer's instructions for the best results.
FAQs
Can you apply new sealant over old?
It is always best to remove any old silicone sealant before applying new. Not only will the existing product probably be dirty (and possibly mouldy, even if you have looked into how to remove black mould from silicone sealant), but it is less likely you will be able to get a good bind between the old and new sealants.
Should a bath be full before you seal around it?
Yes, it might sound odd, but when sealing a bath you should fill it with water before applying sealant. When full of water, most baths sink a little, and this could cause sealant to crack as it 'stretches', if you have applied it to an empty bath.
What colour of bathroom sealant is the most popular?
White is the classic colour choice and will typically work with most styles of bathroom. But, if you need something different, you can always opt for black, grey or clear which is available from most bathroom sealant brands.
How we test bathroom sealants
There's a lot to consider when selecting the best sealants for your bathroom. Thankfully, the Homebuilding & Renovating team is getting hands-on experience with the products in this buying guide to help you feel confident in choosing the right product for you.
In our ongoing independent reviews we are testing the ease of use and drying time to gauge each product’s efficacy, and assessing key factors including whether it's waterproof, and the range of colours it comes in.
Our team is passionate about DIY and home improvement (which probably won’t be a surprise) so we already have detailed knowledge about the brands that make these products.
For more advice on purchasing bathroom essentials, check out our guide to the best bathroom extractor fans, and make sure you know the best bathroom lighting for a safe and well-lit space.
