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f there's one thing that most tileinstallers dislike, it's grouting. Amonotonous, shoulder-wrenching

task, grouting is often delegated to the lowman on the totem pole. That's a big mistake.Nothing can ruin a top-notch tile installa-tion quicker than a bad grout job. An inex-perienced helper can leave shaded orsplotchy grout, uneven joints or grout thatcan be scratched out of a joint with thestroke of a fingernail.

Years ago, white-wall grout was nothingmore than portland cement mixed with wa-ter; floor grout was mixed on the job bycombining fine white sand with cement in a1:1 ratio. Latex or polymer additives weren'tan option, so installers simply added water tothe mix. It worked—tile that was installed50 or more years ago remains intact in manyhomes—but it had its limitations. Colorchoices were usually limited to white, blackor gray. These days, grout is available in arainbow of colors.

Modern grout products are also stronger andeasier to use. The only factors that need con-cern tile installers are the type of grout touse, the proper consistency of the mix, evenapplication and a thorough cleaning. Andthey shouldn't forget additives and sealants.

The width of the joint determinesthe type of groutThere are two basic types of grout: sandedand unsanded. Which type of grout that youuse is usually determined by the width of thejoint between the tiles. Unsanded grout isthe product of choice for any tile installationwhere the joints are less than in. wide,even on floor tile. The finish is smooth, andit is relatively easy to clean.

Primarily used in joints wider than in.,sanded grout (also called floor grout or jointfiller) provides the necessary strength forjoints up to in. and even wider. Althoughyou might get away with unsanded grout injoints slightly wider than in., it's a poor

bet. More than likely, tiny hairline crackswill form as a result of shrinkage, which iscontrolled by sand in the mixture.

As you might guess, the texture of sandedgrout is rougher and a bit harder to clean.Although sanded grout is associated primar-ily with floor tile, it should be used on anytile with wider joints, no matter where it'sinstalled. However, be prepared for a longday if you plan to grout a wall with sandedgrout. Unsanded grout readily clings to ver-tical surfaces, but sanded grout tends to rolldown the wall and end up in little piles onthe floor. It's possible to use sanded grout inthin joints, too, but pushing the thicker mix-ture into tight grout joints can be a frustrat-ing task that typically leaves small pinholesin the grout finish.

Unlike products of ten years ago, mostgrouts on the market now include a latex orpolymer additive that strengthens the groutand helps it to resist staining. Although youcan buy grout without admixes, I don't both-

Choosing, mixing, applying andsealing the messy stuff that goes between tiles

BY DAVID HART

er; I'd rather have the extra protection thatadmixes offer.

To determine the amount of grout you willneed to buy, consult the chart on the back ofevery bag of grout, or ask the sales clerk atthe tile distributor. Measurements are typi-cally based on the square-foot coverage perpound of grout, so you need to know howmany square feet the job is, how wide thejoints are and how big the tile is. One poundof grout might cover 5 sq. ft. of 6-in. by 6-in.tile with -in. joints; a 25-lb. bag of grouttypically covers about 100 sq. ft. of 8-in. by8-in. tile with -in. joints.

A 25-lb. bag of white-wall grout costsabout $10 or $12, and colored grouts cancost a few dollars more. I've used a half-dozen different brands, and all seemed towork well; none stood out as inferior or dif-ficult to work.

Successful grouting depends on theright consistencyOne of the most important aspects of groutis the mix. Nothing can make the process ofspreading grout more difficult than addingtoo little water to the powder. A stiff groutmixture can be nearly impossible to pushacross the tile and into the joints. Converse-ly, nothing can ruin grout faster than addingtoo much water.

I generally mix grout by hand with a mar-gin trowel (sidebar p. 71) in a clean 5-gal.bucket (top photo). When I need a largeamount, I save time by mixing with a paddlebit chucked into a variable-speed drill. Aword of caution here: Whipping the groutinto a froth can create air bubbles that willweaken the mix, so go slowly.

Generally, less water is better. As the waterevaporates from a typical mix, it leaves mi-croscopic voids. Excess water takes up morespace; when the water evaporates, it createslarger voids and weak grout.

What's the right water-to-grout ratio?Most contractors (me included) eyeball theright balance between powder and water.Grout manufacturers usually recommend aratio when mixing a whole bag ("mix 25 lb.of grout with qt. to 4 qt. of clean water,"for instance). But there are times when youwon't use that much, so you have to estimate.I always add less water than I think I need,and then add a little more if necessary.

Both sanded and unsanded grouts shouldhave a stiff, toothpastelike consistency whencompletely blended (bottom photo). Themix should be allowed to sit for about tenminutes and then be mixed again, an impor-tant step called slaking. Slaking allows theingredients to react and the color pigments

to blend, creating a stronger grout with uni-form color.

Working the grout into placeOnce I've mixed the grout a second time, Idump a pile of it onto the floor and startpushing it around with a float held up atabout a 45° angle (drawing p. 70). I want tomake sure the joints are full, so I bear downon the float as I sweep it diagonally acrossthe joints.

I grout a small area, as much as I can reacheasily, then go back and pull the float harddiagonally across the tile, holding the float at

almost a 90° angle. This step cleans off thelarge chunks of grout left behind and helpsto facilitate a quick cleanup later.

When I'm grouting walls, I usually load upa float with wall grout, start at the bottomand spread it up the wall (top photo, p. 71),leaving plenty of grout on the face of the tile.I go back and clean off the excess grout byholding the float at a sharp angle and pullingit across the tile on a diagonal (bottom pho-to, p. 71). As before, I push down on thefloat pretty hard as I pull it across the tile.

In average conditions, grout begins to setup in about 30 minutes, so I try not to spread

Careful mixing controls the ratio of wa-ter to powder. Mixing grout is often aprocess of estimating by eye; watershould be added gradually to the powderto achieve the right mix. Clean water anda clean bucket are important ingredients.

Proper consistency ensures long-lastinggrout. It's important that the final mixhave a stiff, toothpastelike texture that'seasy to work into joints. Too much waterweakens the grout and makes it runny;too little water makes it set up too fast.

THE TRICK IS TO WORKONE AREA AT A TIMEWorking within arm's reach, the author

packs grout into the tile joints with

broad sweeps across the tile face.

Working diagonally on subsequent

passes pushes the excess grout to the

next area.

Keep the float at an angleTo pack grout into joints, apply steady pres-sure with the float held at an approximately45° angle. A second pass with the float heldcloser to 90° will clean excess from the tile.

more than I can work with in that time. If I'mworking in hot rooms or with porous tile, Ispread just enough so that I can start the ini-tial cleanup in 15 minutes to 30 minutes. I'vealso found that grout will set faster if left inthe bucket, so I dump the entire mix ontothe floor and keep it moving until it's gone.

Although cold joints aren't an issue withgrout, there is a chance of color variationfrom one batch to the next. If I have to stop,I try to end at a doorway or clear delineationand feather the next day's work over the old.

Where not to groutGrout won't crack between wall tiles that areproperly installed, except at the junction ofthe tile and an abutting structure like a tubor a countertop. If I'm working with largetiles, I try to minimize the amount of grout Ipack into these expansion joints. Otherwise,I grout everything, use a margin trowel orutility knife to cut out the grout before ithardens and then run a bead of latex-silicone

caulk into the joint. Latex-silicone is easy touse and easy to clean up. Although it doesn'tlast as long as a pure silicone caulk, it does afine job of protecting against water damage.

If you're concerned about matching thatmauve or orange grout, most manufacturersnow sell caulks that are color-matched totheir grouts.

Final cleanup needs less waterCleaning up is as important as choosing andmixing the grout. The initial cleanup shouldaccomplish two things: First, it should re-move the bulk of the residual grout on theface of the tile; and second, it should smooththe joints without pulling out the grout.

When the grout in the joints has firmed upto where it isn't soft to the touch, I startcleaning. How long should firming up take?It varies with room temperature, humidityand the amount of water used in the mixture,but generally, it takes 15 to 30 minutes. If Iwait too long, the grout will dry on the face

Essentialgroutingtools

FLOATS: You can'tgrout without a float(photo right). They'reavailable in two vari-eties: floor floats andwall floats. Wall floatshave a soft rubber pad,while floor floats aremuch stiffer. Althoughsome contractors useboth, I use a wall float forall my grouting; I've foundthat a floor float is too in-flexible to get into tightcorners. A good-qualityfloat can cost $20 ormore and should last upto a year for a full-timeinstaller. Eventually, theedges of the float weardown and won't clean offthe face of the tile well.

MARGIN TROWEL: Thisspatula-shaped tool is es-sential for mixing groutand for scraping it out ofcorners and along base-

boards. It's also good forcleaning your other toolsat the end of the day. Atypical margin trowel willrun about $15 and will lastfor several years.

SPONGES: A good-quality grout sponge willcost $5 or more, but it's anessential tool for whichthere is no cheap substi-tute. I always use largegrout sponges becausethey pick up and holdmore grout than smallerones, and that saves time.

GLOVES: Although sometile installers never wear

rubber gloves when grout-ing, I won't grout withoutthem. I don't like to havewrinkled skin at the endof a long day and, in-evitably, the dry, roughskin that follows. Frankly,there's no reason not towear long rubber gloves.Although I have used gro-cery-store gloves, they'retoo thin and rip far tooeasily. I use a pair ofheavy gloves sold at tiledistributors that havelasted almost a year. Theycost about $8.

KNEE PADS: If you planto spend more than anhour on your knees on atile floor, you need kneepads. It's foolish to workwithout them. A cheappair can cost as little as$5, but you get what youpay for. I have a pair ofplastic-capped, foam-lined knee pads from Alta(707-588-0230) that costabout $35, and they stillprotect me after threeyears of hard use.—D. H.

Wall grout starts at the bottom. To con-trol the flow of grout, the author beginsgrouting low and works upward, packingthe joints with a slightly angled float. Ason the floor example, a strong diagonalpass cleans up the excess.

of the tile, and I'll have to spend time scrap-ing it off. In hot weather or direct sunlight,grout can stick to tile within 15 minutes.

I start with two buckets of clean water, acouple of large sponges, a margin trowel anda grout float. After wetting a sponge andwringing it out, I wipe the face of the tileand the joints with a light circular motion(photo left), rinsing the sponge when thepores become clogged with grout (photo right).If the grout is pulling out of the joints, I waita few more minutes. During this first pass, Iwant to loosen the grout that's drying on thetile. To avoid splotchy color, I also make sureI don't leave puddles of water on the joints. Iuse a margin trowel to scrape clumps ofgrout out of the corners, door casings andany other place where it doesn't belong.

After I've smoothed the joints and loos-ened the grout stuck to the tile face, I goback with a bucket of clean water and re-move the light grout haze that remains.With a clean, lightly dampened sponge, Iwipe diagonally across the tile (photo facingpage) for about 2 ft. or 3 ft., taking care notto push down too hard. I then turn over thesponge, repeat and rinse the sponge. Thisprocess takes time, and if I try to rush it, Iend up smearing grout across the tile. Anystreaks of grout haze left after the secondwipe-down can be removed with a damp ragor mop when the grout has dried.

Cleaning and sealing tileClients often tell me they want a mainte-nance-free floor, but there really is no such

thing, at least not with tile, stone or marble.There is no substitute for general mainte-nance and upkeep; grout gets dirty, period.It's important to clean grout on a regular ba-sis with a plastic-bristle brush and a com-mercial grout cleaner or a solution of mildsoap and water. Make sure the soap isn't oil-based; products such as Pine-Sol and Mur-phy's Oil Soap will darken the grout.

Sealers offer an optional way of protectinggrout from stains; I usually recommend asealer on floor installations. After trying sev-eral formulas available, I've found that theeasiest to use is a water-based penetratingsealer such as TEC's Penetrating SiliconeSealer (800-323-7407) or Custom's TileLabTile and Grout Sealer (800-272-8786),which soaks into the grout and then dries

A clean sponge picks up more grout.When the sponge's pores begin to clogwith grout, the sponge should be rinsedand squeezed nearly dry. Excess water leftstanding on the joints will affect the cur-ing process and discolor the grout.

Cleanup starts with lots of sponge andlittle water. Once grout has firmed up inthe joints, it's important to clean the tileand smooth the joints before the grouthardens. A damp sponge will clean up themajority of the grout (photo left).

Second cleaning removes the grout haze.After the initial cleaning, the remaininggrout residue can be wiped up with aclean, damp sponge and light strokes. It'simportant to rinse the sponge frequentlyduring this stage (photo facing page).

without changing the appearance. (Sealermanufacturers recommend different waitingperiods before sealer application, so consultthe product literature first.) No matter whattype of sealer I use, it's often necessary to ap-ply a fresh coat at least once a year, some-times more often. After first cleaning thegrout joints, I paint the sealer onto the jointwith a foam or bristle brush, allow a fewminutes for it to soak in and then wipe offany remaining liquid. I try not to let the seal-er dry on the face of the tile, but if the sealerdoes dry, a quick scrub with a mild abrasivecleaner removes it. After I apply the firstcoat, I try applying a second coat, but often,it won't soak in. That's okay; it simply meansthe grout is properly sealed. If the secondcoat does soak in (the grout will turn dark as

it would if it were wet), I simply continuewith the rest of the wall or floor.

Other types of sealers include acrylic-basedtop coats that leave a shiny film on the sur-face of the grout and oil-based sealers thatwill permanently darken the color of thegrout. They all work, but each variety leavesa different finish on the grout. Test the seal-ers in a hidden area before you seal the entiretile installation.

Water- and silicone-based sealers are theleast expensive, running less than $20 for aquart. Oil and acrylic types can cost $40 aquart or more.

David Hart is a tile contractor and free-lancewriter who lives in Centreville, Virginia. Photos byCharles Bickford.

Epoxy groutis notfor everyoneAbout ten years ago, the new buzz-word in the tile industry was epoxygrout. It still is the most stain-resistant grout you can find, whichmakes it a great choice for use onkitchen counters and in restaurantsand medical facilities.

It is, however, an unforgiving mater-ial to work. It's sold as a two-part ad-ditive that's mixed with regular groutor as a two-part ready mix that canalso be used as a setting compound;either way, you have to mix the en-tire batch at one time to maintainproper proportions. There's no mixingby eye. It can be used only with ce-ramic tile and can't be removed froma porous surface. Cleaning is often afrustrating experience that involvesremoving excess grout with nylonscrub pads and lots of water (epoxyisn't water soluble). Here, timing isreally important. If you clean beforethe grout has set, the sticky epoxypulls out of the joints and smears allover; wait a few minutes too long,and you'll be hard-pressed to removeit with a hammer and chisel.

Epoxy grout is also expensive. Atwo-part mix that's added to a 25-lb.bag of grout costs about $100 andcovers about 100 sq. ft. of 8-in. by8-in. tile. A smaller batch of two-partready mix costs about $30 per quart.

If this material were just difficultand expensive, I still might use it, butmost regular grouts now include la-tex additives far superior to theircounterparts of ten years ago. Cou-pled with a good sealer, these newerfortified grouts are stain resistantand hold up well under normalhousehold abuse. Given the extra ex-pense, time and elbow grease re-quired by epoxy mixes, I can't thinkof a good reason to use epoxy unlessa customer requests it. I certainlywouldn't recommend it to any neo-phyte tilesetters.—D. H.