Sealing grout is an important part of tile maintenance that helps protect the grout from stains, damage, and moisture. With the right products and techniques, sealing grout can be a relatively easy DIY project for any homeowner. Here is a comprehensive guide on the basics of grout sealing and how to properly apply sealant to get the best results.
What is Grout Sealing?
Grout sealing involves applying a protective coating over the grout joints between tiles. Grout is porous and as a result can absorb liquids, leading to staining, discoloration, and damage over time. Sealing forms a barrier that prevents absorption while allowing the grout to still “breathe”. It provides numerous benefits:
- Protects against stains from dirt, grime, and spills
- Reduces moisture absorption that can cause mildew and mold
- Helps prevent erosion and cracking from exposure to water
- Allows easier cleaning and maintenance of the grout
- Extends the life and improves the appearance of grout
Sealing is recommended for all grout installations, but is especially important for grout in kitchens, bathrooms, and high-traffic areas. Natural stone tiles with grout joints should always be sealed to prevent staining.
When to Seal Grout
Grout should be sealed as soon as possible after installation or re-grouting. Manufacturers recommend applying sealant within 3 days of installation before the grout is fully cured. Sealing at this early stage provides maximum protection.
Re-sealing grout is needed over time as the sealant wears off. How often depends on the type of sealer used, traffic patterns, and exposure to moisture. Typically grout should be re-sealed:
- Once a year for high traffic areas
- Every 2-5 years for low traffic areas
- After professional deep cleaning
- When grout appears dull, discolored, or shows signs of damage
- After repairing or replacing grout
Checking sealant condition yearly is recommended. Doing a water bead test, which involves dripping water onto the grout and seeing if it absorbs or beads up, can help identify if re-sealing is needed.
Types of Grout Sealers
There are many options available when choosing a sealer. Sealers vary in their main active ingredient, durability, ease of application, and other factors.
Silicone Sealers
Silicone-based sealers penetrate deep into grout pores and provide excellent water repellency. They are long-lasting, usually 5+ years for interior use. Silicone sealers allow vapor transmission and grout “breathability”. They provide protection against oil and dirt staining.
Acrylic Sealers
Acrylics form a protective layer on top of the grout joint. They offer stain protection for 1-3 years before reapplication is required. Acrylics are water-based, low odor, and easy to apply. They tend to enhance grout color. Exterior acrylic sealers can breakdown more quickly.
Epoxy Sealers
Epoxy grout sealers provide the most durable, long-lasting protection from stains and moisture. Application is more extensive, requiring proper surface prep and skill. Epoxy forms a plastic-like shield over the grout joint. Reapplication is only needed every 8-10 years for interior use.
Urethane Sealers
Water-based urethane sealers offer similar performance as epoxy at a lower cost. They are more flexible than epoxy and still provide long-lasting protection for 5-10 years. Urethanes are low odor and safe for interiors.
Natural Look Sealers
For a fully natural look, wax-based sealers are available. These penetrate like silicone and provide water repellency without altering appearance. Wax sealers require more frequent reapplication but provide a natural, non-glossy finish.
How to Seal Grout
Sealing grout properly takes a little planning and preparation for best results. Here are the basic steps:
1. Clean the Grout
Grout should be fully clean before sealing to allow maximum penetration. Use a grout brush and grout cleaner to scrub away all dirt, grime, soap residue, and deposits from the grout lines. Vinegar, hydrogen peroxide, or bleach can also be used for disinfecting. Rinse thoroughly with clean water and allow to dry fully.
2. Mask Surrounding Areas
Use painter’s tape to mask off any areas you don’t want to get sealer on, such as the tile surface, fixtures, baseboards, etc. Remove any sealer that gets on tiles right away as it can be hard to remove once dried.
3. Prepare the Work Area
Have proper ventilation in the room and cover any nearby furniture or surfaces. Work in small sections for easiest application and to prevent lap marks. Make sure you have enough sealer on hand to complete the project.
4. Follow Sealer Instructions
Read the product directions fully and be sure to follow any specific instructions for surface prep, application tools, number of coats, drying time, curing, ventilation, cleanup, etc. Don’t take shortcuts.
5. Apply the Sealer
Use a small paintbrush, cotton balls, or sealer applicator bottle to apply a thin, even layer of sealer completely over the grout joints. Avoid puddling sealer on the surface. Allow each coat to dry fully per the label directions before adding more coats.
6. Remove Excess Sealer
Wipe off any shiny film or sealer from the tile surface using a clean, dry cloth. This prevents buildup and residue that can be hard to remove later.
7. Allow Proper Cure Time
Follow manufacturer’s instructions for full curing time before use. Avoid water exposure or cleaning for at least 72 hours. Check that ventilation is adequate.
8. Repeat Annually or as Needed
Re-seal grout once a year or more frequently depending on traffic and exposure to maintain maximum protection.
Grout Sealing Tips and Tricks
- Use a reputable brand of sealer like Aqua Mix, DuPont, Miracle Sealants, etc. for best quality.
- Don’t skimp on coverage when applying – make sure to fully saturate the grout lines.
- Seal any repairs or replaced grout right away before curing starts.
- Apply when humidity is low and temperature is 50-90°F for proper drying/curing.
- Stay off sealed floors for 8-12 hours for minimal disturbance while curing.
- Wipe up spills quickly after sealing as absorption will still occur over time.
- Re-seal after professional steam cleaning or stripping to renew protection.
- Spot seal high traffic areas more frequently as needed.
Grout Sealing FAQs
Should I seal all grout or just problem areas?
Sealing all grout joints is recommended for complete protection. Sealant will wear unevenly if only applied in high traffic zones.
How soon can I get the sealed grout wet?
Wait at least 72 hours after application and follow manufacturer’s instructions before regular use or cleaning. Premature water exposure can ruin the protective seal.
Can I seal over stained or discolored grout?
No, sealing will trap stains underneath. Re-grouting or using a grout colorant is recommended for freshening up stained grout before sealing.
Is sealing grout myself worth the cost?
Absolutely – hiring a pro just for grout sealing costs much more. With proper products and methods, DIY grout sealing is easy and affordable.
Should I use a penetrating or surface sealer?
For grout, penetrating silicone or urethane sealers are best to get into the porous structure for long-lasting protection.
How do I know if I need to re-seal my grout?
Check annually. Signs like darkening, visible staining, cracking, powdery grout, and water absorption indicate sealing is needed.
Can I use boiled linseed oil to seal grout?
No, it will turn grout dark and can lead to extensive staining. Use a proper grout sealer only.
Conclusion
Regular sealing of grout with a quality sealant protects against water, stains, and damage to maintain the clean, finished look of any tiled surface. Allowing proper cure time and re-application as needed will provide maximum benefit. With the right precautions and products, grout sealing can be done successfully as a DIY project. Consistent sealing will greatly extend the life of grout and enhance the beauty of any tile installation.
