More questions?

Frequently Asked Questions

Can you Plaster over Drywall?
  • Yes! The major difference between drywall and plaster board is the absorption rate of the paper used on the face of the board. Plaster board has a higher absorption rate than drywall. The down side to using drywall for plaster is that the base coat will remain "wet" for a longer period of time.
  • Note: Green Board or Moisture Resistant board should not be used for plaster due to the intentional nature of the board to resist moisture absorption. Link to Types of Board
  • Do not turn the drywall backwards for plaster application! The finish paper of the board only wraps around the backside for a short distance. Very often this strip is not completely glued down and when plaster is applied will get wet and the seams may show badly or begin to pop up in spots.
Does it matter what kind of board I use?
  • The simple answer is YES? For an explanation of each kind of board goto TYPES OF BOARD.
  • Board usage on ceilings may be one of the most confusing areas to explain but lets try to make sense of it:
    1. 16" on center joists.
      1/2" board is acceptable (plaster board included), however, 1/2" High Strength (drywall), 1/2" Sag Resistant (drywall) or 5/8" (drywall and plaster board) is suggested. Two factors to consider: local fire rating code and insulation use. If you plan on putting over 6" of insulation in the ceiling you may want to consider going to 5/8", 1/2" High Strength or 1/2" Sag Resistant board to minimize the sag factor, this in turn will help limit call backs and future problems. For meeting fire code ratings please check your local building code requirements.
    2. 24" on center joists.
      1/2" high strength, 1/2" sag resistant or 5/8" board (including plaster board) is acceptable. Once again, local fire rating codes may dictate 5/8" or otherwise to meet the building codes of your area. Please check your local building code requirements.
    3. Laminating over an existing ceiling:
      1/4" or 3/8" drywall/plaster board can be used to laminate over an old ceiling. To do this properly, the board hanger must still screw into the ceiling joists. As a helpful hint, consider using drywall construction adhesive such as Ohio Sealants #38 or Miracle Adhesive and laminating screws in the field (the space between the joists) to minimize sagging.
How do I fix cracks in walls?
  • The most widely used method of fixing cracks in plaster or drywall is to "V" out the crack with a tool such as a can opener (the ones you use for tomato juice). This is assuming that the plaster/drywall is sound and still attached solidly.
  • Use a positive set compound such as USG's Durabond or Solid Product's Sudden Bond and a small trowel (margin trowel) or putty knife to force the mixed compound into the "V" created earlier. Note: Always follow the mixing instructions by the manufacturer for best results.
  • It is very difficult to exactly match the old plasters texture or a drywall texture, but some hints are: for a sand finish, some try to blend the repaired area in with a sand texture paint. For a smooth finish, please take your time while applying the compound. Some light sanding may be required if excess compound is used, and for a "textured" wall use your imagination (such as a small paint brush, a rag or stipple brush) to try to create the same texture as the original while the compound is still in a semi-cured state.
  • Prime the repaired area and repaint wall and blend the repaired area as best as possible.
How do I patch a hole in Drywall?
  • For very small holes (diameter of a quarter or smaller), a positive set compound such as Durabond or Sudden Bond can be used. If needed, use two coats and sand smooth.
  • For larger holes (door knobs, chair hits, etc.), using a sharp utility knife, trim the broken area back to form a clean, uniform square or rectangle. Slide a block of wood inside the wall and secure to one edge of the cut out lengthwise, leaving 1/2 of the wood block visible. Drywall screw this into place. Continue this process until all 4 edges have this "backing" block of wood. Cut your replacement piece of drywall to fit the trimmed out hole - set into hole and screw to visible wood blocks. Tape and finish as normal (see How Do I Tape Drywall Joints for Taping Methods).
  • Note: Two handy items on the market is called an Instaback or Drywall Frog and Straight Flex Patches from Confirm Int'l. These items are designed to to assist in the repair of holes. The Drywall Frogs come in two sizes, 1/2" and 5/8". They are inexpensive and they work well!
How do I patch old plaster?
  • Plaster, like drywall, is a "system", using a substrate, a base coat and a finish coat. To make the best repair this system should be emulated, meaning, that if possible the same type of materials should be used. Note: curing times for plaster products vary due to environment conditions, product type and application thickness.
  • For small holes such as door knob hits and assuming the substrate, blue board or lathe material, is sound (if the substrate is broken, repair as needed first. Substrate: Blue Board, Plaster board, wood or metal Lathe):
    A. For thin coat plaster (each of two layers are about the thickness of a dime), using a small trowel or putty knife, reapply base coat (Kal-Kote base coat or Imperial base is suggested however a positive set compound such as Durabond or Sudden Bond can be used) to the original thickness. Allow proper curing time according to package instructions. After base is cured, use the same trowel or putty knife to apply the finish coat (Kal-Kote sand texture, smooth texture finish or Imperial Diamond is suggested), feathering the edges to make a smooth transition from the patch area to the original finish. Using Durabond or Sudden Bond for both the base and finish coat can be done, but remember, you are not emulating the original system. This will negate the manufacturer warranty.
    B. For full coat plaster (the stuff in the older houses). Clean patch area of all loose base and finish coat materials down to the lathe (substrate). Using Gypsolite plaster or Structolite, apply the base coat to the same thickness as the original base coat (usually around 3/8") leaving room to apply the finish coat to maintain a flush repair area in comparison to the rest of the wall. When the base has set (please read products instructions), apply appropriate finish coat (Kal-smooth, Kal-texture or Diamond finish). Prime and repaint wall.
How do I repair nail pops?

Nail pops are one of the easiest repairs to do. The first thing that needs to be done is to reset the nail (i.e. the head of the nail should be slightly recessed). This can be done with the rounded end of a screw driver or a ball peen hammer, tap lightly until nail head is recessed into a small dimple, but do not break the paper or through the board. Next step is to take a small putty knife (a 2" or 3" blade works well) and a small amount of your favorite drywall compound. Using the swiping motion of an "X" (meaning, swipe from left to right, then from top to bottom) fill dimple level with compound. It is possible that you may have to fill the hole twice. The first time may shrink, requiring more compound to be added. Sand smooth, prime and repaint the wall.

How do I Tape My Drywall Joints?
  • We can't beat the masters at this one. Allow us to Hyperlink you to the USG joint treatment page. Goto USG Joint Treatment Page
Why are there different kinds of drywall compounds?
  • Primarily the different kinds of compounds are directly associated to the job they perform.
  • A positive set or all purpose compound is designed to be used in the first coat (tape embedding) of drywall finishing, or in setting trims such as corner beads or the various flexible trim beads available, such as Paper Face Tape-on Bead, No Coat Beads, and Vinyl Trim-Tex or Vinyl Corp. Characteristics are: Higher adhesion, harder, more difficult to sand and less shrinkage.
  • The lightweight or topping compounds are designed for the second and third coat of the taping process. Characteristics are: Lightweight, easier to sand, a more "workable" compound.
  • Note: positive set or all purpose compounds are the preferred compound for decorative texturing of walls or ceilings because of the strength and adhesion benefits.