Top 10 Installation FAQs

1.  How much will decking boards shrink and how should I install them?

Preserve CA decking
  • Treated wood is often still damp when delivered, so it is recommended to butt deck boards tightly together during installation as they will shrink slightly in width and length as they dry out. This will create acceptable gaps between the boards for water to drain off the surface.
  • How much a board will shrink will be dependent on how much moisture remains in the wood after it was installed.
  • If the wood is allowed to dry prior to installation, a small gap should be left between boards.
  • Ultimately, your deck boards should have an edge gap between ¼ inch and ⅜ inch to allow for proper ventilation, draining and for debris to pass through.
  • Wet or dry, boards should be installed tight end-to-end.

2.  Which side of the deck boards should be facing up during installation?

  • Always use the best-looking side of a deck board for the deck surface.
  • Install the deck board with the grade stamp down to prevent having to sand it off.

3.  What end of posts should be installed in the ground?

  • Install the un-cut end of support posts in the ground for ground contact applications.
  • Field-treat the cut-end, the top of the post. See the FAQ below, “What should I use to apply to the cut ends of my lumber?”

4.  Do I need to pre-drill pilot holes at end of boards?

predrilling pilot holes for screwing down decking
  • Yes, pre-drill pilot holes to prevent damage to the wood and allow the screw to better fit into the wood. Drilling pilot holes help prevent wood from splintering and cracking when installing screws.
  • The drill bit for the pilot hole should be smaller than the screw’s body, not including its threads.
  • Drill the pilot hole perpendicular to the wood. Drill slowly into the wood to the depth of the length of the screw. Back out the drill bit slowly as not to widen the hole.
  • Drill pilot holes at least one inch (25 mm) from the board ends and 5/8” (16 mm) from the board sides. If the screws are installed too close to the edge, you run the risk of splitting the boards.
  • Drive the screw flush with the wood. Do not overdrive the screw. You can use a drill stop or tape to mark off the screw’s length on the drill bit.
  • Butt boards tightly together during installation as they will shrink slightly in width and thickness as they dry out.

5.  What screws and connectors are recommended?

  • For the best results, use building-code approved, corrosion-resistant screws/fasteners and connectors for all exterior wood projects.
  • Hot-dipped galvanized steel is recommended and should conform to ASTM A153 for fasteners and ASTM A653, G185 for connectors.
  • For coastal installations, use code approved stainless steel.
  • Stainless steel offers the best protection. Type 304 or higher stainless steel is recommended for very wet environments such as poolside deck. Type 316 or higher is recommended for exposure to salt or saltwater.
  • Caution: Do not mix metals: Use stainless-steel fasteners with stainless-steel connectors and galvanized fasteners with galvanized connectors.
  • Ecolife® is pressure treated wood treated with DCOI, a non-metallic preservative and can be used in direct contact with aluminum products, including flashing, even in continuously wet applications.
  • Direct contact of Preserve® CA treated wood with aluminum products is not recommended.
  • For permanent wood foundations and corrosive environments, such as areas with saltwater spray, stainless steel fasteners are recommended.

6.  Can nails be used in building my deck?

  • You can use nails or screws to build your deck. However, screws are more secure and don’t pop out of the wood like nails do, making them the superior option for securing the deck and for safety.
  • Nails that pop out of the deck can become a nuisance, not to mention they can injure your feet or those of your loved ones.
  • Use screws to improve holding performance. Nails don’t fasten the deck as securely or for as long a period as screws do.
  • Install fasteners flush to the wood surface. Do not overdrive fastener as this will create a concave depression in the surface of the wood that allows water to penetrate the wood.

7.  What is hot-dipped galvanizing?

  • Hot-dipped galvanizing is a process of coating zinc over bare steel to provide a protective layer.
  • The bare steel is cleaned, pickled, fluxed, and then dipped in a molten bath of zinc and allowed to cool prior to inspection and shipping.

8.  Should I use stainless steel or hot-dipped galvanized fasteners?

SS wood deck screws
  • Wood treated with copper formulations can have a corrosive effect on some metals — in some istances the nails and screws that are used to hold boards together. Therefore, if local building code requires the use of stainless steel or hot-dipped galvanized fasteners, use them.
  • Take steps to ensure that any metal touching treated wood treated with copper formulations will not develop corrosion problems.
  • The use of stainless steel and hot-dipped galvanized fasteners is a logical choice to make when it comes to fasteners and connectors for your treated wood decking made with copper-based preservative formulations.

9.  What should I use to apply to the cut ends of my lumber?

field treating end cuts and holes
  • For field-cut ends and drilled holes in treated lumber, use a brush-on wood preservative.
  • Copper naphthenate formulations are available from home centers, lumber dealers and hardware stores.
  • Deck stains and sealers do not provide adequate protection.
  • Building codes and the American Wood Protection Association (AWPA) Standard M4 requires "all cuts, holes and injuries such as abrasions or holes from removal of nails and spikes which may penetrate the treated zone shall be field treated." The extra effort protects the longevity that the preservatives offer.
  • Another two preservatives, oxine copper and inorganic boron can be used for field treating in above ground applications.
    • Oxine copper can be used for applications originally treated with oil-borne or waterborne preservatives. Oxine copper preservatives, containing the recommended minimum .675% oxine copper (0.12% copper metal), are available colorless or in various colors and have little odor, according to
    • Inorganic boron can be used in applications originally treated with a waterborne treatment and in areas continuously protected from liquid water.
  • Be sure to follow the preservatives’ application instructions.

10.  How do I remove the grade stamp from my deck?

  • In most cases, a light sanding will remove or lighten the grade stamp.

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