FINISHING/REFINISHING MANUALWood flooring that carries the NOFMA/WFI trademark/certification is a precision-made product of endur-

ing beauty. The proper finish enhances both grain and color and protects the wood. Poor quality or poorlyapplied finish allows the wood’s natural beauty todeteriorate and creates an unneeded maintenanceproblem.

In this manual we have incorporated many years of practi-cal experience. Described are some methods and productsthat give a beautiful, lasting finish to newly installed oakand other hardwood flooring. How to restore the beauty toexisting hardwood floors that have become unsightly fromwear or neglect is also covered.

NOTE: This manual covers only the sanding andfinishing methods. Installation of hardwood flooringover different types of construction isdescribed in Installing HardwoodFlooring, the manual available onthat subject from the Wood FlooringInstitute.

Should you encounter a situationnot covered here or have additionalquestions, contact NOFMA: TheWood Flooring ManufacturersAssociation, Technical Department forassistance. Phone (901) 526-5016 from8:30 a.m. to 4:30 p.m. Central Time,Monday through Friday, or FAX(901)526-7022 any time.

Acceptable floor finishing materialsare produced by many manufacturers,who have also developed application pro-cedures appropriate for their products.Read the manufacturer’s instructions thor-oughly BEFORE proceeding with finishing.The instructions given here are of a generalnature...

Where they vary from the label instructions of theproduct or equipment being used ALWAYS FOLLOW THEMANUFACTURER’S DIRECTIONS WITH REGARD TOSAFETY EQUIPMENT AND INSTRUCTIONS.

FINISHING/REFINISHING MANUAL

NOFMA/W

FI9

WOOD FLOORING

FINISHINGHARDWOODFLOORING NOFMA/WFI

TECHNICALSERVICE

WHEN TO BEGIN THEFINISHING PROCESS

Since a near-occupied environment was establishedprior to installation, it is recommended that unfinishedflooring be allowed to acclimate 1 to 3 weeks beforeproceeding with sanding and finishing operations.This acclimation allows the flooring to react and moveas the environment dictates so that slight cracks,slightly raised edges, etc., can be sanded, filled, andfinished to give the best appearance. Longer periodsof exposure to job site abuse and moisture can result infuture problems.

After finishing is completed, temperature and hu-midity should continue to be maintained at nearoccupancy levels.

NEW FLOORS - Applying the finish to the hard-wood floor should be one of the last jobs of any con-struction project. This prevents the traffic of workmenfrom marring the finish. Wall coverings should be inplace and painting completed except for a final coaton the base molding.

OLD FLOORS - Remove all furniture, rugs, anddraperies from the room. If you’re planning on wallrepair, painting or applying wall covering, do thatwork before you refinish the floor so paint or pastewill not drip on the new floor.

SANDING EQUIPMENT NEEDEDA drum or belt wood floor sanding machine, an

edger or spinner, appropriate sanding paper or beltsand edger discs, in COARSE, MEDIUM and FINEgrits. (See TIPS #2)

NOTE: The drum or belt sanding machine thathas a separate lever for raising and loweringthe sanding drum is preferred. The leverprovides additional control during the sandingprocess. Always wear ear protection.

A floor polisher 15” to 17” diameter, 200 rpm or less,with a sanding disc attachment and sanding discs orsanding screens in fine grit, also white or brownbuffing pads.

Hand tools and miscellaneous equipment: broom, vac-uum, hammer, 6d to 8d case nails, nail set, nail puller,long handled paint scraper, hand sanding block andsandpaper, 2”- 3” putty knife and prepared wood filler,oscillating electric sander - if available. For repairingboards: circular saw, 1/2”-1” chisel, pry bar, hand saw,block plane, wood glue, drill, utility knife, replacementflooring.

PREPARING THE FLOORFOR SANDING

Sweep the floor clean immediately before sanding.Inspect the floor carefully - tighten any loose boardsby face nailing with flooring cleats or 6d to 8d flooringnails, preferably into joists, look for any protruding

Fig. 1. Before sanding an old floor remove the base shoe.Use a wood wedge behind the pry bar to protect thebaseboard from damage by the bar.

NOTE: If the base shoe and base have been paintedmany times, leave them in place.

nail heads or nails not driven down below the wood’ssurface, pull them out or counter-sink them with a nailset and replace any damaged or defective flooringboards (sanding exposed nails can produce sparks cre-ating a fire hazard in the sander dust bag).

SANDING A NEW STRIPOR PLANK FLOOR

Load the drum sander with a coarse grit to mediumgrit sandpaper (See TIPS #3 & #4). Place the machinealong the right hand wall (unless making an anglepass as described in TIPS #5 through #7), with abouttwo-thirds of the length of the floor in front of you.Start the motor with the drum raised off the floor,walk slowly forward at an even pace and ease thedrum to the floor. As you near the wall at the end ofthe pass, gradually raise the drum off the floor.Practice before turning on the machine.

Cover the same path you made on the forward cutby pulling the machine backward and easing the drumto the floor as you begin the backward pass.

When you reach your original starting point easethe drum from the floor. Move the machine to the leftside approximately three to four inches. Then repeatthe forward and backward passes and move to theleft after completing each set of passes. You will onlysand a 3” to 4” wide strip of un-sanded area with eachset of passes. When the two-thirds area of the roomis sanded, turn the machine in the opposite directionand sand the remaining third in the same manner.Be sure the sanding passes made in the one-thirdarea overlap the first passes by two to three feet. Thisblends the two areas together.

After completing the first sanding operation, or“cut”, with the drum sander, use the edger to sandalong the baseboards, up to corners, in closets, andother areas the drum sander did not reach. With newflooring, which is relatively smooth, use the next grit

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Fig. 2. To load the drum sander, thread sandpaper into theloading slot, turn the drum a full revolution andslip the other end of the sheet into the slot. Tightenby turning the nuts at both ends of the drum. Don’tovertighten and over-compress the drum rubber,which stresses sanding paper, widens slot, andincreases chatter. Some sanders may take sandingsleeves or belts. Others may have a clamp to holdpaper on the drum. ALWAYS UNPLUG sander whenchanging paper.

sandpaper that will be used on the drum sander. Withold flooring it may be necessary to use the same gritpaper as the first drum cut to remove old finish orlevel abused areas. (See TIPS #9)

If a medium grit cleans and sands the floor com-pletely, use it for the first cuts. If extra passes are re-quired to clean and level the strips go to a more coarsegrit paper. The first cut with drum sander and edgershould produce a level, completely sanded floor (withcorners and obstructions to be scraped later). All fol-lowing sanding procedures merely remove the sandingscratches produced by the first cut. (See TIPS #10)

When using the edger move in an easy quarter-

Fig 3. Never let the sanding drum touch the floor unlessyou are moving the machine forward or backward. If thathappens you will cut a hollow in the floor that is difficultto remove. (See TIPS #8)

circle pattern at end walls overlapping into the drumsanded area 4”-6”, and following the direction of thegrain, to some extent. (See Figure 5.) Do not try tomake the edger cut more aggressively by putting extrapressure to the front. This merely makes ridges andgrooves which are hard to remove. Along walls parallelto flooring direction, move back and forth with thedirection of the flooring, also overlapping into thedrum sanded area. The edger typically cleans a 1” to2” strip on each pass.

After drum sanding the floor with a coarse gritsandpaper, repeat drum sanding with a medium gritsandpaper. For the edger, use fine grit sandpaper. Ifcoarse was used on the first cut use medium grit and

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Fig 4. Sand in the longest direction of the room, starting at the right-hand wall. Move forward and backward, then move the machine to yourleft a few inches and make another pass. After sanding two-thirds of the room, turn the machine 180’and sand the remaining one-third.

Fig. 5. Use the power edger to sand up the baseboard andin other areas the drum sander won’t reach. Followthe direction of the grain along side walls. Endsanding strokes along the grain at the end walls.Overlap into drum sanded area.

follow with fine grit on the edger. Complete the sand-ing operation using the fine grit sandpaper on thedrum sander.

Generally, filling of nail holes, blemishes, cracks,etc., should be done before the fine sanding cut. Use acommercially prepared wood flooring filler. Somefillers may need coloring or may not take a bleachingoperation; check with the supplier or manufacturer.

Also, it may be necessary to trowel fill the entirefloor, particularly an old floor, due to the extent ofcracks between strips. Multiple character marks foundin #1 and #2 COMMON Grades which are fillablegrades may also require trowel filling. Trowel fillingshould be done before the medium or final sandingcuts. Let the filler dry thoroughly before proceedingwith the sanding. (Overnight is best.)

When drum sanding and edging are completedproceed to hand scrape and then hand sand cornersand around doors and other cased openings. Also handsand the perimeter edges. Use the same grit as thelast cut. Using a sanding block or electric oscillatingsander can facilitate the hand sanding process. Ifstaining the floor a dark color, the electric oscillatormay leave egg shaped marks which will show in thestain. Hand sand these out or do not use the oscillator.

When using a hand scraper apply even pressure,scraping in the direction of the grain. Avoid gougingthe wood with the scraper. A brick with a piece of oldblanket glued around it makes a good sanding block.Sand about 6” into drum sanded area. Always sandand scrape in the direction of the grain along thelength of boards.

Fig. 6. Ahand scraper is used where the edger does notreach, and to remove old finish in tight spots.Always scrape in the direction of the flooring grain.Then hand sand or oscillate scraped area. Stripper(See TIPS #9) may be used where scraping is dif-ficult, such as under radiators or between stairbalusters.

Using a sanding disc (one grit finer) or screen disc (samegrit as fine cut) on the buffer over the entire floor canalso improve blending of edged and drum sandedareas. (See TIPS #11) Move buffing machine back andforth with the direction of flooring boards.

If the floor is to be stained a light to medium color,the fine sanding cut with 80 grit sandpaper leavesthe wood fibers open and enables more stain to pene-trate, producing a deeper shade and more uniformappearance. An option is to screen with an 80 gritafter the fine sanding cut, particularly if the fine cutwas 100 grit. Use of the buffer and screen increasethe risk that circular scratches will show if a darkstain is applied.

Fig. 7. Parquet, block, herringbone and similar floors.

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Three sanding cuts followed by screening or discingis the recommended procedure and will provide a uni-form surface for most all standard finishes. Two cutsfollowed by the screening or discing operation may besufficient but may produce a more coarse surface andis considered a minimal sanding procedure.

SANDING PARQUET, BLOCK AND SIMILARPATTERNED FLOORING - Use the drum sanderand edger for two sanding cuts. With the first cut donot sand directly across or with the pattern but alwayson an angle. Start the first sanding cut diagonal tothe grain using a medium grit sandpaper. Then usefine grit sandpaper for the second cut on the oppositediagonal. Use the buffer and screen or disc to makea final fine cut with the room’s longest dimension.(See Figure 7.) (A coarse first cut is usually notnecessary.)

REFINISHING AN EXISTING FLOOR - Mostsolid wood flooring is 3/4” thick and can be sanded andrefinished a number of times. Thinner wood floors,solid or engineered - 1/2” or 3/8” thicknesses - should berefinished with caution because repeated sandingscan wear down the groove edge, causing breakage orwear through to reveal nails. With laminated floor-ing, professional sanding is recommended.

To determine the floor thickness remove a floorheating register or the shoe mold and baseboard sothat an edge of the flooring can be measured.

When refinishing floors, remove as little of thesurface as is absolutely necessary. This is particularlytrue with veneered and thinner floors. On square edgestrip flooring that is face-nailed, all nails must bedriven slightly below the surface of the wood to permitsanding.

The following instructions apply to standard 3/4”strip, plank and block floors and, with the cautionsjust mentioned, to the thinner materials.

Sanding. It may be necessary to use a very coarse“open coat” paper to remove the old finish. The heatand abrasion of the sanding operation make the oldfinish gummy and may quickly clog normal sandingpaper. First try regular paper (particularly on adiagonal). If 90% of the finish is removed and the flooris generally flattened, coarser grits are not necessary.(See TIPS #3) When you get down to new wood usethe same procedures and grits as previously describedunder “Sanding a New Strip or Plank Floor”. If theold floor has been painted several times it may be nec- essary to use paint remover to uncover the woodsurface. (See TIPS #12)

The number of sanding passes required for“Refinishing” will be largely determined by the con-dition of the old floor and the thickness of the finishbeing removed. If the surface is in very good shape,with only light scratches and few dents, and has nobuild-up of old finish and wax, one pass with the disc

sander and fine paper may be sufficient. Be sure allthe old finish is removed.

If the floor has been abused, scarred or dished, useas many cuts as are necessary to get a smooth,unblemished surface. If badly scarred and abusedboards have not been repaired, it may be advisableto leave some blemishes in the floor or too muchsanding may be required. (See TIPS #2 #5 #8)

With a floor that is in fair condition, make the firstcut at a 45°± angle to the flooring direction withmedium grit paper to level the floor and remove 90%of the finish. Then follow the instructions given forsanding a new floor on the succeeding cuts. Use thesame grit paper as was used on the 45° cut for thefirst cut parallel to the flooring strips.

PREPARATIONS FOR FINISHINGIMPORTANT: Allow ample time with the sand-ing procedure to apply the first coat of stainor other finish the same day that sanding iscompleted. This prevents a raised grain con-dition which creates a rough surface.When machine and hand sanding are completed

sweep and vacuum the floor. Wipe up and/or vacuumall dust on windows, sills, doors, door frames, andbaseboards.

Inspect the floor carefully. Spot-fill missed cracksand nail holes with a commercial flooring filler, appliedsparingly with a putty knife. When dry, hand sandwith fine sandpaper, same grit as final sanding.

IMPORTANT: Check with finish manufacturer orsupplier to make sure fillers are compatible withfinish materials.

For future re-finishing, it is essential to know thebrand names and color of the stain and other finishingproducts used, or if the floors were prefinished at theflooring manufacturing plant.

FINISHINGImmediately after sanding is completed the

finishing process should begin. This process in-volves applying a protective coating and a color, if de-sired, to the flooring. Finishing produces a uniformlyenhanced surface and seals the wood to make it lessabsorbent to moisture and foreign materials.

GENERAL TYPES OFFINISH MATERIALS

IMPORTANT: Read entire label before apply-ing finish and use only compatible products.Compatibility questions between differentmaterials should be referred to the finish man-ufacturers.

Always follow ALL of the manufacturer’s safe-ty precautions, especially for skin contact,ventilation, breathing apparatus, fire hazardsand disposal.

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Penetrating Seal. This sealer soaks into the woodpores and hardens to seal the floor. It wears only asthe wood wears, will not chip or scratch and is gen-erally maintained by thin applications of wax. Afteryears of wear the floor can usually be restored withoutsanding by cleaning it and applying another coat ofsealer or a special reconditioning product. Worn areascan usually be refinished without showing lap markswhen new finish is applied over the old. A penetratingsealer may also contain stain which colors the woodwhile sealing it.

Stain or stain sealer combination. Staining is thefirst step in the finishing process if other than anatural finish is desired. The oil stain with a pene-trating sealer in combination is generally easiest toapply and accomplishes two things, coloring andsealing, in one application. Stain only (without sealers)requires more care with the application in order toavoid uneven coloration and lap marks. A stain onlygenerally requires 8 hours or less to dry (Readdirections). The combination products (stain andsealer) require at least overnight or up to 48+ hours todry in stagnant, damp, or humid conditions.

Fast-drying sealers and stains. These products shouldbe used only by a person who is accustomed to han-dling and applying them. The mechanic should be ableto complete the job within the allotted drying time toavoid lap marks or a splotchy appearance.

With a sealer/wax system, most manufacturers rec-ommend two coats of a penetrating sealer, then wax.A reconditioning product is generally available foruse when traffic or other conditions cause discolorationor wear of the finish. These reconditioning productsrestore the floor to its original appearance withoutthe need for sanding.

With a surface finished system, one coat of sealergenerally followed by two coats of the surface appli-cation produce satisfactory results. FOLLOW THEMANUFACTURER’S DIRECTIONS.

Application: Stain or penetrating sealer can beapplied by hand wiping with rags, by brushing, orwith a lambs wool applicator. Start application in onecorner along one edge of the room and move with thedirection of the flooring. Use a paint brush to applyto flooring at wall lines. “Cut in” about 2” or 3” fromwalls to avoid smearing moldings. Apply liberally withrags along the length of the starting wall in a stripyou can reach across.

When using an applicator apply a heavy streak ofmaterial along the grain; leave about one foot of spacefrom the wall-side application. Go to where this stripewas started. Do not re-dip; use the excess material tofill in the empty space, wiping across the grain.Maintain a uniformly stained area to a particular lineor run of boards across the room.

Distribute material evenly, do not leave puddles or

Fig. 8. Along-handled lamb’s wool applicator is excellentfor applying penetrating seal finishes or pigmentedwiping stains. Spread generously in the directionof the grain; wipe up excess.

a heavy excess on the surface. Wiping up the excesscan follow almost immediately after the applier movesaway from the corner area. The length of time thestain is allowed to remain on the floor, to some extent,will determine the degree of color tone. Use clean ragsand wipe up the excess material left on the surfaceof the flooring. Repeat the application and wipingprocess, working parallel to the stained area acrossthe room. Be sure to overlap by one strip into pre-viously stained area and wipe the overlap well or elsean area that appears darker (a lap mark) can result.

NOTE: Do not allow stain/penetrating sealer todry before wiping. DO NOT allow water drops,sweat, or bare hands and knees, etc. to come incontact with the unstained and stained areasor discoloration and imprints will result.

After completing the first coat allow to dry overnightor longer, as necessary. Use a #1 steel wool pad orwhite or brown fiber buffing pad on a floor buffer andbuff the floor. Clean, vacuum, and dust residue. (SeeTIPS #13 & #14) If only stain was used, apply sealeras the next step.

If the SEALER / WAX SYSTEM is the final finish,apply a second coat of sealer and allow to dry. Neutralcolor should be used if no additional colorant isrequired. After drying, if rough to the touch, thissecond coat should also be buffed with #1 steel woolor a fiber pad, and the floors cleaned of residue. Pastewax or liquid buffing wax is then applied and buffedto a satin sheen with the buffing machine. (SeeProtecting the Finish Page 9) To apply a thin coat ofpaste wax place a walnut size glob of wax in an oldcotton athletic sock. Heat from the hand will melt thewax as the pad is rubbed over the floor; let dry beforebuffing.

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SURFACE FINISHES - These finishes remain onthe surface of the floor and form a protective coating.

Polyurethane, “Swedish Finish”, Moisture CuredUrethane, and Water Based Urethanes to name a feware blends of synthetic resins, plasticizers, and otherfilm-forming ingredients. All are durable, moisture-resistant finishes. These finishes are generallyavailable in high-gloss, semi-gloss, satin and matte,except moisture cured urethane. Any one of them is agood choice for a kitchen where there is exposure towater splashing or spills.

Oil Modified Polyurethane is generally the mostcommon surface finish. It is durable and moisture-resistant, and generally the easiest to apply. This typefinish tends to amber slightly as it ages.

Water based finishes (Urethane and/or Acrylic com-binations) These are clear, durable, non-yellowingand are non-flammable at time of application. Theygenerally have advantages similar to Oil ModifiedUrethanes without the odor of mineral spirits, andthey dry much faster.

Moisture Cure urethanes are harder and moremoisture resistant than the other surface finishes andare generally available only in gloss. They cure byabsorbing minute quantities of moisture from the air,which causes them to dry and harden. Relativehumidity is critical to the curing process. Follow manu-facturer’s directions. These finishes are extremelydifficult to apply properly and are best left to the pro-fessional.

“Swedish Finishes” (Acid Cure Urethanes) are alsodurable finishes, generally harder than polyurethanes.They are clear, fast drying and resist yellowing. Type

Fig. 9. When using a brush to apply a surface finish, workin the direction of the boards in a path narrowenough to keep a wet edge. Lap strokes back intoarea just covered.

of undercoat, working time, number of coats, and otherfactors are all critical and make application difficult.These finishes should be applied ONLY by the highlyskilled.

If a SURFACE FINISH is to be applied (i.e.Polyurethane, Water Based Urethane, etc.) after theapplication of stain and sealer, be sure the floors arecompletely dry. Follow by buffing the sealed floor with#1 steel wool, a buffing pad or a fine screen and com-pletely vacuum up residue. (See TIPS #14)

NOTE: If water based urethane is to be appliedNEVER use steel wool. Steel fibers rust oncontact with water and will discolor the finish.Use an abrasive nylon screen or fiber buffingpad (white or brown).

Oil Modified Polyurethane APPLICATION.Follow manufacturer’s instructions and safety rec-ommendations. Turn off open flames (don’t forget pilotlights) and shut off AC/heating units, if recommended.Stir material well but avoid bubbles. Pour into cleanpaint tray or bucket. Apply to flooring with brush orlambs wool applicator. Start application along oneedge of the room with the direction of the flooring.Cut in at the wall with a paint brush. ApplyPolyurethane along the length of the starting wall ina strip you can easily reach across.

Brushing. Fill 1/3 of brush with finish, dab off excessdrip, apply a liberal amount with smooth even strokesalong the grain. Watch out for splattering. Do notover-brush which will introduce bubbles. Work fromwhere finish has not been applied into the area thatis still wet, feathering out the lapped areas.

Applicator. Fill applicator with finish, dab off excessdrip, and apply across the strip direction in shortstrokes, working toward previously wet area. Straighten cross strokes with a single gliding strokealong strip direction, feathering into previously appliedwet area and lifting the applicator up.

Fig. 10. Professional floor finishers generally use a single circular steel wool pad about 1/2”thick. With a new sharp pad,start in a clos-et to avoid cutting into finish or stain.

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Apply finish in parallel strips across the room. Alwaysmaintain a “wet” edge. Don’t retouch missed areas(holidays) if finish has begun to skim over. The nextcoat will fill these areas. Allow to dry overnight.

When dry walk over the floor, especially perimeterexterior walls and feel corners. If the finish soundsor feels tacky it is not dry. WAIT FOR IT TO DRY.Buff the completely dry finish with #2 steel wool pador a used 120 grit screen, or hand sand with 120 to150 grit sandpaper.

NOTE: If finish does not powder when buffing,additional drying time is recommended. Tackyfinish residue can knot up and accumulate onthe buffing wool, screen, or sandpaper andscratch the finish.

Merely dull all the finish. Don’t forget to hand sandor steel wool corners and edges. Too much buffingremoves finish material to the extent the sealer/stainis exposed or removed. (See TIPS #13)

Vacuum up all dust. Tack floors with a lint-freetowel (wrapped around a bristle broom) and slightlydampened with water or 100% mineral spirits. Letfloor dry completely.

Apply second coat. A third coat may be desired forincreased protection and durability. Buff betweencoats to dull the surface.

Water Based Urethane APPLICATION. Followmanufacturer’s instructions. Turn off AC or Heatingunits, if recommended. Pay particular attention tocoverage figures, open time, and when-to-buffinstructions. Use catalyst, if required, stir in and letstand if recommended. Pour finish into non-metal trayor bucket. Apply to flooring with brush recommendedfor water based materials, paint pad, or manufacturersupplied applicator.

Most water based materials are applied by pouringa “small river” along the starting wall near the “cut in”area. The applicator “plows” this material along thedirection of flooring the length of the room with excessdirected toward unfinished area. As finish materialis used, re-pour the “small river” and continue appli-cation. Open doors or use fans to exhaust moistureladen air when finish films over and is dust free tofacilitate curing. Some manufacturers recommendbuffing the rough raised grain after the first coat.Some recommend application of a second coat in 3-5hours without buffing. Follow buffing directions anduse fiber pads or screens. A third coat is generally rec-ommended. Application of more than two coatsin one day is generally not advised.

NOTE: Do not over-work material. Keeprenewing the small river of material and be sureto maintain a wet edge in order to avoid gapsand excessive foaming.

WHITE FLOORSBLEACHING. Bleaching is generally used to

lighten the natural coloration and subdue the darkercharacteristics of flooring. Bleaching is generallyfollowed with an application of a white or pastel stain.Application of these products should be done by theprofessional. Before using a bleach be sure the flooringis clean and free from oils, grease, and old finish thatmight repel the bleach and give an uneven effect. Useonly bleaches specified for wood flooring and followapplication and drying directions carefully. Someproducts need neutralizing after application. Extratime is required to complete the bleaching processand allow complete drying.

It’s a good idea to make a test area in an incon-spicuous place, since the length of time the bleachremains on the floor and the amount used will affectthe degree of color removal. Also, bleaching WhiteOak can result in a greenish coloration.

The bleaching process should be done onlyonce.

A white stain may be applied before the surfacefinish. (See TIPS #15) Check that all products arecompatible with the stain and/or sealer used and thata non-ambering surface finish is used. The finalsanding cut with an 80 grit paper is advised withwhite stains. This promotes absorption of the largercoloring particles of the stain into the flooring. Besure the excess stain is wiped from the surface. Followby buffing when stain is dry. Stain residue on thesurface of flooring can interfere with adhesion of thefinal finish.

NOTE: Seasonal cracks, surface discolorations,and dirt are VERY noticeable and may be objec-tionable in a white floor.

RECONDITIONINGYou should first determine what type of finish is on

the floor so appropriate materials can be used.

To determine if a floor was originally finished witha penetrating seal, scratch the surface with a coin orother sharp-edge object in a corner or some otherinconspicuous space. If the finish does not flake off,a penetrating seal was probably used and a recondi-tioning product can be applied to restore its originalbeauty. TEST AN AREA.

If the finish flakes in the corner, a surface finishwas probably applied to the flooring. Next check forwax. Wax interferes with intracoat adhesion so re-coating over wax is not recommended. Attempt tosmudge the surface in the same corner with yourfinger. If a smudge is evident, wax is probably presentand complete re-sanding and finishing is indicated.

With Surface Finishes which have not been waxedyou can recondition by re-coating if the finish has notbeen worn away to expose bare wood.

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To re-coat surface finishes first remove furniture,etc. Next clean floors with a non-residue cleanerdesigned for polyurethane on wood floors or non-aromatic 100% mineral spirits. Dull the finish surfacewith steel wool, a sanding screen or paper as requiredby the type of finish used for re-coating (See appro-priate finish section) Apply a compatible finishusing appropriate application techniques asdescribed in finishing.

CAUTION - Adhesion between coats of surfacefinishes is affected by wax, grease, and some main-tenance products, as well as some types of stains,bleaches or sealers. One brand or type of finish maynot be compatible with another. Check with manu-facturer for compatibility. Make a test in a closet orsome other inconspicuous place to be sure the finishwill adhere and dry properly. This is particularlyimportant when refinishing an old floor since someof the old finish may have penetrated the wood belowthe level to which it is sanded.

OTHER FINISHESVARNISH AND SHELLAC - These products were

commonly used as floor finishes before today’s modernformulations were introduced. However, they arerarely used today, and generally are not consideredas durable as the modern finishes. Shellac is notrecommended for use as a floor finish since itshows water spots readily. NITRO-CELLULOSELACQUERS are hard and brittle and scratch easily(very flammable when applied).

STENCILING - Decorative borders or overall floorpatterns can be applied to hardwood floors with theuse of stencils. However, this job should be done bya professional finisher familiar with these procedures.

PROTECTING THE FINISHPenetrating Sealer. For the final touch of beauty

and to protect the sealer, apply a coat of good wax.Use either a liquid buffing wax or paste wax. Use onlybrands that are designated for hardwood floors. If aliquid, be sure it has a solvent base (has the odor ofmineral spirits) and does not contain water.

The wax will give a lustrous sheen to the floor andform a protective film that prevents dirt from pene-trating the finish and will help prevent scratches.

Be sure the finish coat is thoroughly dry beforeapplying wax. Apply a thin coat of wax, let dry andbuff with a #1 steel wool pad. For increased lusterfollow by buffing with a polishing pad or a thick pilewool carpet remnant.

Waxing a commercial installation creates aslipperiness hazard. Gymnasium and roller rinkfloors should never be waxed. They requirespecial maintenance procedures and products.

Surface Finishes. If you wax a polyurethane finishit can not be re-coated, but must be sanded and re-finished when wear patterns become prominent.

NOTE: Most manufacturers of surface finishesdo not recommend waxing. Check manufact-urers recommendations.

MAINTENANCEWood floors, properly finished, are the easiest of all

floor surfaces to keep clean and new looking. Unlikecarpeted or resilient floors that show age regardlessof care, wood floors can be kept looking like new, yearafter year, with minimum care.

What is minimum care? A good rule of thumb is tovacuum or dust mop weekly. Always check with themanufacturer for their recommendations oncleaning and maintenance. If the floor is waxed,occasional buffing helps remove scuff marks thatmay appear in the wax coating. A waxed floor needonly be re-waxed once or twice a year, or as often asneeded in heavily traveled lanes using a paste wax,liquid buffing wax, or wax/cleaner combination.Wax-coated finishes should never be cleaned withwater, not even with a damp mop. Read the label.

For surface finished floors (polyurethane and thelike), before you use any cleaner, check with themanufacturer of the finish used on that floor fortheir recommendations.

Do not generally wet a floor with water or anycleaner which requires mixing with water. A clothor mop wetted with water and squeezed dry may beused to wipe up food and other spills, provided thearea is buffed dry immediately.

Never intentionally pour water onto a floor.Excessive amounts of water may find a way to seepbetween the boards or into scratches causing woodfibers to swell and affect the finish.

GYM AND ROLLER RINK FLOORSThe procedures for sanding and finishing a wood

sports floor are similar to those described for otherwood flooring installations. Type of finish(es) andnumber of coats are generally established withincontract and plan specifications.

Use only products approved for such applications.Follow the specific finishing instructions providedwith each product. Deviations from the recommendedprocedure may affect quality and performance ofthe finish.

OVERALL APPEARANCEFor more details on the care of your floors, write

the Wood Flooring Institute and request a “Wood FloorCare Guide”.

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GENERAL OUTLINEFor Sanding

NEW or EXISTING FLOORS NEW or EXISTING FLOORSIN GOOD CONDITION IN ROUGH OR ABUSED CONDITION

Inspect Repair and Clean

Belt/Drum Sander- Coarse Cut 36 or 40 grit Diagonal Coarse Cut 36 or 40 Belt/Drum Sander- Straight Coarse Cut 36 or 40Edger- Coarse Cut 36 or 40Edger- Medium Cut 50 or 60 grit

Clean and SweepBelt/Drum Sander- Medium Cut 50 or 60 grit Medium Cut 50 or 60

Edger- Medium Cut 50 or 60Clean and Sweep

Spot Fill or Trowel Fill Floors if NecessaryEdger- Fine Cut 80 or 100 grit Fine Cut 80 or 100Belt/Drum Sander- Fine Cut 80 or 100 grit Fine Cut 80 or 100

Clean and SweepHand Scrape Corners and Inaccessible Places

Hand sand perimeter and scraped areas or use oscillating sander if stain is to benatural to medium brown.

Use buffing machine and fine screen.

Clean and VACUUMSeal or Stain and Seal

Steel Wool* or Screen or use Fiber PadClean and VACUUM

SEAL AND WAX FINISHES- SURFACE FINISHES*Apply 2nd coat sealer Apply 1st finish coat

Screen or steel woolWax Clean, VACUUM, TackPolish Apply 2nd finish coat

If necessary screen or steel woolClean, VACUUM, TackApply 3rd coat

*Do not use steel wool with water based finishes.

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After reading this Manual and performing thedirected tasks either by you or a professional, yourbeautiful hardwood floor will be ready to be inspectedfor acceptance.

Inspection should be done from a standing positionwith normal lighting. Glare, particularly from largewindows, magnifies any irregularity in the floors andshould not determine acceptance.

A finish similar to that found on fine furnitureshould not be expected. Trash in the finish, a wavylook along strips, deep swirls or sander marks, and

splotchy areas can be indications of inadequate fin-ishing or cleaning. The quality of the finish can beacceptable and still include some of these problems,but they should not appear over the entire floor.

The perimeter and hard to reach areas (i.e. underradiators, around cabinets and cabinet cut-outs,closets, corners, etc.) are most likely to contain theseirregularities.

Again, when inspected from a standing positionthese irregularities may be present but should not beprominent.

1. Use personal protective equipment as recom-mended by manufacturer.

2. Generally used floor sanding grits:Very Coarse - 20, 24, 30, (open coat)Coarse - 36, 40Medium - 50, 60, 80Fine - 80, 100, 120Very Fine —120, 150

3. The sanding operation should remove a minimalamount of wood, less than 1/32”

4. If a medium grit will level the floor or remove oldfinish on the first cut, it is not necessary to use the more aggressive coarse grit for the first pass.

5. For rougher floors the coarser grits are recom- mended.

6. If the floor is uneven, cupped or crowned and nomoisture problem exists, make the first rough cutat a 45° angle to the direction of the flooring.Make succeeding cuts parallel to the direction ofthe flooring.

7. Use the same grit paper on both the 45° cut andthe first rough cut.

8. If a slight hollow or deep scratch is present in thefloor, make multiple angle passes forward andbackward across the area. Start the first pass ata 30° angle to the hollow or scratch. Work fromboth the front and back of the blemish. Repeatedsandings made directly across the blemish makeit larger. After the blemish is removed, sand thearea with the grain to straighten all sandingmarks.

9. Always carry a soft lead carpenters pencil whilesanding, and immediately mark exposed nails,slight hollows, excessive scratches, holes to befilled, etc. Pencil marks across the floor beforethe intermediate sanding cuts also show if theentire floor was sanded.

10. To change from coarse to medium to fine grits,do not skip more than one intermediate grit. (i.e.40 skip 50 use 60, 60, skip 80 use 100)

11. A sanding disc on the buffer is more aggressivethan screening. Use the next finer grit whendiscing to avoid swirl scratches.

12. CAUTION: Some strippers contain wax and otherchemicals which can interfere with the finish.Check with the manufacturer.

13. When buffing sealers/stains, or between finishcoats, always start in an inconspicuous place or acloset. A new pad can aggressively cut too deepand remove stain, producing a lightened area, orremove too much finish and not give adequatefinish thickness.

14. When using a white or brown buffing pad to buffstain/sealer, check the pad frequently for discol-oration which can mean the stain/sealer is notdry and that additional drying is needed.

15. It is not always necessary to bleach before usinga white stain. The desired white color may beachieved by the stain only. Staining withoutbleaching is easier and more trouble-free and doesnot soften the surface of the wood.

TIPS FOR STRIP/PLANK FLOORING:

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OTHER WFI PUBLICATIONSOF INTERESTInstalling Hardwood Flooring - Information oninstalling hardwood flooring in many types of construction.

Wood Floor Care Guide - How to keep hardwood floors beauti-ful with minimum care; tips on stain removal and other subjects.

Copies of these manuals are available on request to the WoodFlooring Institute, P. O. Box 3009, Memphis, TN 38173-0009.

Most major producers of wood flooring in the United States aremembers of NOFMA: The Wood Flooring ManufacturersAssociation, an organization that upholds industry standards.The NOFMA/WFI trademark/certification on flooring is yourassurance of quality and that it was produced by a member ofNOFMA/WFI.

NOFMA: The Wood Flooring Manufacturers Association, 22 North Front Street, 660 Falls Building, Memphis, TN 38103P. O. Box 3009, Memphis, TN 38173-0009

901/526-5016FAX 901/526-7022

Web Site www.nofma.orgeMail info@NOFMA.org

Printed in USARevised March, 2002

The specifications and in-structions contained hereinsupersede all previous andundated publications fromNOFMA/WFI.

3-1-2002

NOFMA: The Wood Flooring Manufacturers Associationsupports sustainable forestry and the responsible stewardship

of all natural resources.

NOFMA/WFITECHNICALSERVICE