Renovation 4th Edition

by Michael Litchfield

  migrates through the smallest openings, so use

  painter’s tape to seal the perimeters of closed

  doors and keyholes. Because baseboards will get

  bumped by edgers, remove them—though often

  that’s not possible. Alternatively, you can use a

  metal shield to protect trim, as shown in the top

  left photo on p. 568. Vacuum the floor so you can

  survey it closely for nails sticking up and floor-

  boards that are split or uneven. Use a nail set to

  sink nails below the floor surface. If boards are

  uneven or cupped, you may be able to sand them

  down evenly if they are solid wood. If any boards

  are split or splintered, replace them now.

  Before you start sanding floors, cover cabinets, air registers, and other fixed

  elements with plastic sheeting. To seal edges, use blue painter’s tape to avoid

  lifting off paint or cabinet finishes, but remove the tape as soon as possible.

  edger; both use the same grit on each pass. To

  screen the floor before finishing, buff with

  100-grit screens backed by a nylon backing pad.

  To smooth between coats, use a 220-grit screen

  or hook-and-loop sandpaper strips that attach to

  the buffer pad.

  Note: If floors are coated with paint or wax—

  which gum up sandpaper quickly— use open-coat

  sandpaper for the first sanding pass. You can use

  regular closed-coat sandpaper (most sandpaper

  is closed coat) for subsequent passes.

  If you’re simply recoating a finished floor, you

  probably won’t need a drum sander and an edger;

  a buffer with a nylon pad and two grades of

  screen (100 grit and 220 grit) should do the job.

  Again, check your floor finish’s label to see what

  To prevent sanding over the cord, keep the excess

  looped over your shoulders. Drum sanders sand

  grit sandpaper to use between coats. Finally,

  whether you’re going forward or backing up, so as

  sandpaper wears out quickly, so get more than

  you back up, continually pull the cord away from

  you think you’ll need. Most rental companies will the path of the sander.

  566 Chapter 20

  replacing a Floorboard

  to remove a damaged board, drill holes across it so you can pry it out in

  splinters, using a hand chisel. or you could cut into the damaged board by

  Bottom leg of

  using a circular saw set to the depth of the flooring and then pry out pieces

  groove removed

  with a flat bar. to make this pocket cut, rest the heel of the saw on the floor,

  pull back the saw guard, and slowly lower the front of the saw sole until the

  turning blade engages the wood. Be careful: Holding a blade guard back is

  never advisable if you can avoid it, and the saw may jump when it engages the

  wood. let the blade stop before you lift the saw.

  Find a replacement board that’s similar in color and grain: try to pull a

  board from a nearby closet or from a floor section that’s usually covered by an

  appliance. Hold the board next to the hole and use a utility knife to mark off

  the appropriate length. to make the replacement fit more easily, slightly back-

  Subfloor

  bevel its lower edges on a tablesaw. if the stock is tongue-and-groove, use a

  tablesaw to cut off the lower leg of the groove. apply construction adhesive to

  To insert a replacement board into an existing

  the underside of the new board, then drive it into the opening using a piece of

  tongue-and-groove floor, use a tablesaw to

  scrap to cushion the hammer blows. it’s not possible to nail the board through

  remove the bottom of the groove. Slightly

  its tongue, so predrill and face-nail two 6d-finish nails at either end. use a

  back-cut the ends of the new board so it will

  nail set to drive the nails below the surface. Fill the holes with wood putty.

  slide in easier.

  Sanding FloorS

  A quick review: Shut off all pilot lights, seal off

  doorways, open windows for ventilation, wear a

  zzzzzz overlap Sanding Passes

  FIRST PASS

  respirator and ear protection, and start with the

  Overlapping passes

  Two-thirds floor length

  least aggressive sandpaper. If that grit isn’t cut-

  Starting point

  ting it, you can switch to a more aggressive sand-

  paper. Remember: Lower the sander drum only

  when the machine is moving.

  Start sanding with the drum sander. Sanding

  with the direction of the wood grain cuts less

  aggressively and minimizes scratches that must

  be sanded out later. However, if there are high

  Sanding

  direction

  spots that need to be sanded down or if the floor

  is painted, sand diagonally to the wood grain on

  the first pass, then with the grain on all subse-

  Overlap sections

  quent passes. (The diagonal angle should be 15º

  slightly.

  to 30º from the direction of the floorboards.) If

  you must sand the first pass diagonally, use the

  same grit on the second pass, as you sand with

  the grain. Because a parquet floor has grain run-

  ning in various directions, sand it diagonally on

  One-third

  floor length

  the first pass, too.

  Using an edger.

  SECOND PASS

  After completing each sanding

  pass with the drum sander, use the edger to sand

  along the perimeter of the room, as close to the

  Start along a wall and sand about two-thirds the floor length.

  base of the walls as you can get. Use the same

  Sand up and back. Then raise the drum, and roll the sander

  grit sandpaper that you just used on the drum.

  over so the next pass overlaps by roughly half a drum-width.

  When it’s upright, the sander disk moves in a

  Sand until you reach the opposite wall. Then turn the sander

  clockwise direction, so work from left to right,

  180° and sand the remaining third of the floor.

  keeping the edger moving constantly to avoid

  scour marks. You don’t need to press down on

  Flooring

  567

  Edgers sand right up to the base of a

  wall, but they are aggressive sanders

  with plenty of torque. To avoid

  scuffing baseboards and casing, cover

  the edger bumper with masking tape

  or, if possible, have a helper shield the

  woodwork, as shown.

  Hand-scrape the areas the edger can’t reach. Scrape

  with the wood grain, before sanding lightly with a

  sanding block.

  the edger to make it work. If the edger is sanding

  too aggressively, switch to the next finer grit. If

  it’s not sanding aggressively enough, change its

  sanding disks more often. Again, try to sand with

  the wood grain as much as possible.

  Finish up by hand. Hand scraping and sanding

  take care of the areas the edger can’t reach, such

  as in corners and under cabinet toekicks. It’s

  hard, tedious work, but fortunately there’s not

  much of it. A sharp scraper will speed the job,


  scraping with the grain to remove the old finish.

  Then use a sanding block to smooth out the

  semicircular edger marks. ( Note: If there are a lot

  of edger marks, use a random-orbit sander to

  feather them out.) Once you’ve drum-sanded,

  edged, and hand-scraped the room, vacuum it

  well before switching to the next-finer grit and

  sanding the floor a second time. If you need to

  fill holes or gaps in the floor, do it before the

  second sanding.

  SCrEEning FloorS

  After you’ve drum-sanded and edged the floor

  with 100-grit sandpaper and vacuumed it well,

  use a buffer with an abrasive screen to smooth

  out any remaining marks. Use a 100-grit or

  120-grit buffer screen, which is held onto the buf-

  fer pad by friction. Because the buffer rotates

  slowly and the screen is flexible, you can buff

  right next to the base of the wall. Start along a

  wall, moving the buffer from side to side (it

  rotates in a counterclockwise direction). As you

  did with the drum sander, overlap passes about

  one-half the width of the buffer pad. Buffer

  screens wear out quickly, so replace them when

  you’ve screened one-third to one-half the floor.

  Save at least one used screen so you can fold it

  Between finish coats, screen the floor to improve adhesion, using a 100-grit or and use it to hand-screen the corners where the 120-grit screen. Before applying the next coat, vacuum and dry-mop the floor buffer couldn’t reach.

  well with a tack rag.

  568 Chapter 20

  To achieve an even smoother finish, vacuum

  Wood stains penetrate and don’t really seal.

  the floor and wet-sponge it with clear water the

  When they have dried, penetrating sealers are

  night before screening it (the moisture will raise

  often waxed to make them more durable. But

  the grain slightly). The next day, when the wood

  waxed floors are durable only if they’re regularly

  is dry, screen it smooth. Wetting the wood and

  maintained, which takes time. Thus most floors

  then screening it is called popping the grain.

  today are sealed with surface finishes, which

  P R O T I P

  Popping is optional but strongly recommended if don’t require waxing.

  you’ll be applying a water-based finish. After

  Surface finishes, as their name implies, form

  screening the floor and touching up corners by

  a tough exterior shell to resist scuffs, scratches,

  if you’re using a water-based

  floor finish, apply a water-based

  hand, vacuum the room thoroughly and use

  and moisture. The earliest surface finishes were

  sealer first. Sealers help topcoats

  clean tack rags to remove dust from any horizon-

  shellac and varnish, which have been largely

  adhere, deter stains, and seal the

  tal surface. (A tack rag is a slightly sticky cheese-

  replaced by oil-based and water-based polyure-

  surface so you can apply thinner,

  cloth pad that attracts dust.) Finally, dry-mop the thanes. Shellac has poor water resistance and

  more uniform topcoats. Follow

  floor, wrapping the mop in a clean cloth lightly

  chips easily, and varnishes tend to be strong

  the manufacturer’s guidelines to

  dampened with the same solvent you used to thin smelling and slow to dry. Besides, both are

  make sure the sealer is compati-

  the floor finish.

  extremely flammable. Although surface finishes

  ble and that you use the correct

  require less maintenance, their disadvantage is

  grit between coats.

  SElECting a Floor FiniSH

  that they can’t be touched up when they become

  worn, so you must refinish the whole floor.

  Floor finishes are often divided into two catego-

  Surface-finish sheens range from matte (little

  ries: penetrating sealers (penetrants) and surface

  shine) to satin to semigloss to gloss. In general,

  finishes. Penetrating sealers usually contain

  glossier finishes are harder, more durable, and

  plant-based oils, such as tung oil or modified lin-

  more water-resistant.

  seed oil, and soak into wood fiber. In time, they

  As you’ll see, polyurethanes vary greatly in

  harden to seal and protect the wood. Because

  ease of installation, drying time, and durability.

  penetrating sealers form a hard outer shell, they

  Water-based polyurethanes are the stars of the

  can be easier to touch up by sanding lightly and

  show these days: tough, nonyellowing, relatively

  adding more sealer if wood becomes scuffed or

  mild smelling, and fast drying (two to six hours).

  scratches—touched-up areas won’t be obvious.

  Finishes, Cleaning Solvents, and applicators

  finish

  cleans with

  aPPlicator

  comments

  water-based

  

  Soap and water

   Synthetic brush; pad;

   Probably best all-around finish for nonpro; tough,

  polyurethane

  round applicator

  water-resistant finish; easy cleanup, low smell;

  work fast, overlapping edged areas before they dry

  oil-based

  

  Mineral spirits

   natural-bristle brush;  tough, durable finish; favored by pros because it

  polyurethane

  round solvent-resistant

  dries slower than water-based; slightly stronger

  applicator

  smell while drying

  Penetrating sealers  Mineral spirits

   lamb’s wool applicator,  Slow to dry; strong odor; scratches easily but can be

  (tung and modified

  natural-bristle brush

  touched up with new finish over old; usually waxed

  linseed oils )

  stain-sealers

  

  Mineral spirits

   Varies: natural-bristle  Same profile as penetrating sealer; finish must be

  brush to clean rags

  waxed to protect wood

  Varnish

  

  turpentine

   natural-bristle brush;  Volatile; strong smelling; slow to dry; hard, amber

  or paint thinner

  lamb’s wool pads

  finish gives historical appearance; often used to

  match older finish

  shellac

  

  denatured alcohol  natural-bristle brush;  Poor water resistance; flammable; chips; rarely

  lamb’s wool applicator

  used for floors anymore

  Various (acrylic-

  

  Proprietary

   Computer-monitored

   Factory applied in highly controlled environment;

  impregnated; acrylic-

  solvents

  sprayer

  durable; water-resistant coatings on prefinished

  urethane; uV cured)

  wood flooring

  Flooring

  569

  Start each coat by cutting an edge

  around the floor’s perimeter and

  along cabinet bases, using a brush or

  a paint pad. Then use a T-bar
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  applicator to overlap the edged

  borders while they’re still wet.

  For newer, water-based polyurethanes, use a round synthetic T-bar applicator like this one. Pour the finish onto the floor, then spread it in broad sweeps—like window washing with a squeegee.

  And brush cleanup is easy with soap and water.

  Because they contain lower levels of VOCs,

  water-based polyurethanes also are safer to use.

  Despite their volatility, oil-based polyurethanes

  are often applied by professional refinishers

  because they’re slower to dry and thus allow

  more time to even out coats. Although solvent

  based and stronger smelling, oil-based polys are

  more durable and water-resistant, and they turn

  a handsome amber with age. Let them dry for

  24 hours before recoating or walking on them.

  Moisture-cure polyurethanes are the most durable

  of the lot, but because they must absorb moisture

  from the air, they’re temperamental to apply,

  slow to dry, and best left to professionals.

  Finally, there are surface finishes that require

  highly controlled environments and thus are fac-

  tory applied to prefinished flooring. This group

  of finishes may include aluminum-oxide, titani-

  um, or ceramic additives to resist abrasion and

  may require UV curing, rather than heat curing.

  Some of the toughest of these finishes infuse

  acrylic into the wood cells in a modern version of

  a penetrating sealer.

  Use a lamb’s wool applicator to apply penetrating-

  oil finishes.

  570 Chapter 20

  aPPlYing a WatEr-

  BaSEd Floor FiniSH

  Stirred, nOT SHAkEn

  Applying a water-based polyurethane does not

  don’t shake clear floor finishes to mix them as

  differ much from applying an oil-based finish

  you do paint. shaking will entrap air bubbles

  and, as noted in the preceding section, water-

  and leave blemishes—popped bubbles—when

  based finishes are more benign. Although

  the finish dries. instead, stir finishes thoroughly

  “Finishes, Cleaning Solvents, and Applicators” on

  from the bottom of the can. don’t thin finishes.

  p. 569 offers general guidance, always follow the

  manufacturer’s instructions.

  if stirring doesn’t dissolve the finish “skin”

  or other solids, strain the finish through a

  Cutting the edge is the first step when apply-

  paint strainer.

  ing any type of floor finish. Use a brush or paint

  pad to apply a 6-in. swath of finish around the