To prevent mold and mildew on grout, ensure proper ventilation in your kitchen or bathroom by using exhaust fans or opening windows during and after hot showers or cooking. As a general guideline, you may need to regrout every 5 to 15 years.
To remove damaged grout, use a grout saw or a rotary tool with a grout removal attachment. Be careful not to damage the surrounding tiles. After removing the old grout, clean the area thoroughly, let it dry, and then apply new grout following the manufacturer's instructions.
But for the rest of us who tend to neglect this aspect of our homes (trigger warning: mold), we’re broaching the dirty subject and providing answers that show the way to leak-free, mold-free cleanliness.
The goal: sparkling-clean grout, as in Athena Calderone’s revamped bathroom.
Photograph by Sarah Elliott.
Grout and caulk: What’s the difference?
Both grout and caulk are used around tile, but they’re not related, says Sallick. Even though grout and caulk are different, much of the advice that follows applies to both—whether they’re in a bathroom or kitchen, on a wall or on a floor.
A strip of newly-installed caulk is blissfully clean and mildew-free.
See DIY: Refinishing a Bathtub for more of this project; photograph by Liesa Johannssen.
What’s the best way to keep grout and caulk looking new?
To prevent stains, mold, and calcium buildup, particularly on grout, Sallick has three basic pieces of advice: Seal, clean, and ventilate.
The tile and grout need to dry out after the shower or tub has been used.”
See Philadelphia Story: Two Creatives Tackle Their Own Kitchen; photograph by Michael Persico.
Another place where regular cleaning can help prevent dirty grout: the kitchen backsplash.
Does grout need to be resealed?
Grout is porous, and it doesn’t stay waterproof forever. Depending on how often the shower is used, the grout needs to be resealed, and that’s something you can do yourself.
A lot of grout to keep clean, in a floor-to-ceiling tiled shower by the architects behind Solveig Fernlund Design and Neil Logan Architect—though the choice of darker grout will help conceal dirt.
Should I use a daily spray on grout?
When it comes to preventing the buildup of mold and grime in the shower in particular, many people swear by spraying down the shower each day.
Not completely necessary, Sallick says: “If your shower is properly sealed, you don’t need to spray daily—cleaning once a week is fine.” But for a shower that gets a lot of use, or a bathroom that’s not well ventilated, it can’t hurt to spray the tiles regularly.
My grout is already stained and discolored. How do I clean it?
If you’re moving into a rental or haven’t kept up with regular maintenance, you might have grubby-looking grout on your hands.
A trick to minimize the appearance of dirt: In a bath tiled completely in olive green, New Zealand designer Katie Lockhart opted for darker grout.
Photograph by Neeve Woodward, courtesy of Katie Lockhart Studio.
My grout is cracked and crumbling. What can I do?
Don’t neglect this, because water seeping through cracked grout will cause the wall and floor to rot. Note that your grout might be crumbling because either you didn’t hire a really good professional to install it or you didn’t maintain it properly (i.e., regular cleaning and resealing).
Caulk needs care in the kitchen too. Here a bead of caulk runs the seam between two marble slabs in Steal This Look: A Small but Smart Kitchen in Brooklyn.
Photograph by Matthew Williams for Dwell Magazine.
I’ve neglected my caulk and there’s mold underneath it. What to do?
If you haven’t effectively prevented mold built-up, your caulk may be beyond cleaning. This is another case where you have to remove the old caulk first, clean the area meticulously so no mold remains, and then replace it with fresh caulk.
Though, say, a kitchen backsplash isn’t exposed to as much water, Sallick offers the same advice: Keep it clean.
Grout in the kitchen versus grout in the bath: Should I care for them differently?
Photograph via Joanna Laajisto Creative Studio.
In good shape: the original tiled floor and grout at A Caviar Bar in Finland with a Wintry Palette.
What about grout on a tiled floor?
Install it properly by sealing it twice, and then care for it by keeping it clean.
“If you’re persnickety about the grout on your tiled floor, you need to take a brush and clean it to bring it back to the original color,” Sallick says.
Tiled walls and ceilings in An Unfussy Brooklyn Townhouse Remodel from Architect Elizabeth Roberts; photograph by Dustin Aksland, courtesy of Elizabeth Roberts.
When it comes to the threats of mold and mildew, Sallick says, “It’s all horrible. You need to prevent it at all costs, and you can do that by keeping your bathroom and kitchen clean.” For much more advice on the care and keeping of the bath and kitchen, see our Bath Guide and Kitchen Guide.
Is there anything else I should know?
How do I clean and maintain grout in my kitchen or bathroom?
To clean grout, start by scrubbing the surface with a mixture of warm water and mild detergent using a brush or sponge. After cleaning, rinse the grout thoroughly and let it dry.