Installation Instructions

Pressure treating lumber forces preservatives deep
into the wood bers leaving the wood clean, workable,
and highly durable and is designed for outdoor projects
like decks, docks, swing sets and fences. AC2
®
treated
wood is backed by a Lifetime Limited Warranty against
damage caused by fungal decay and termites (See
warranty for details). Wood is a renewable resource
that is an excellent choice for outdoor projects; however,
when something is built with wood (pressure treated
or not) and exposed to the weather, certain inherent
properties of the wood become evident. Treated or
untreated wood may warp, twist or cup in varying
degrees, depending on stresses released by moisture
changes. Similarly, lumber may develop surface checks,
splits or sap may exude as the wood seasons. These
are not defects but natural tendencies. Left unprotected
or unrestrained, all wood is likely to exhibit these
tendencies. While pressure treating does not warrant
against such natural occurrences, there are measures
you can take to greatly reduce their likelihood.
Proper application of materials, workmanship and
maintenance are keys to any successful project.
Recommended joist spacing for thick deck boards is 16"
to 24" spacing. 16" is always better and certainly no more
than 16" if boards are applied at an angle. The pressure
treating process forces preservatives and water deep into
the wood cells causing the wood to swell. During the
A high percentage of warping and twisting can be avoided
with proper fastening. We recommend fastening with
stainless steel or triple coated deck screws. These fasteners
Any exposed wood, pressure treated or not, should be
protected from the weather. Application of a quality clear
water repellent or semi-transparent stain, which contains
water repellent, will help minimize the effects (checking,
cupping & warping) caused by the cycles of moisture
take-up and loss the wood goes through outdoors. First,
determine if the product has been pressure treated with a
factory applied water repellent by looking at the end tag.
If it is not factory water repellent treated, thoroughly clean
your project with a deck cleaning product. Clear water
repellent can be immediately applied to your deck or other
project and is highly recommended. If you choose to use
a semi-transparent stain which contains a water repellent,
you need to rst check that your project is surface dry.
Either wait until the surface is dry or immediately apply
clear water repellent and wait approximately 8 weeks and
then apply your chosen color of semi transparent stain.
If the products contain a factory water repellent, an oil
based stain can be applied in 30 - 60 days and water
Sap is naturally occurring in wood and is set in the wood
during the manufacturing process at the lumber mills.
Extreme weather conditions allowing boards to heat up
excessively over a prolonged period of time may cause
the sap remaining in a piece of lumber to run or ooze out
of the wood. Direct sunlight can affect and inuence this
occurrence. Dark stain colors may possibly allow the wood
to absorb more heat, contributing to sap presence. Factors
affecting cooling airow, such as too little space between
deck boards, completely closing in the bottom of a deck
with no ventilation installed, obstructions from bushes or
shrubs could also negatively affect the deck surface allowing
heat build up and the appearance of sap. Eventually most
sap will come out of the wood, but this may take a season
or two and some clean up. (Continued on back)
Deck Board Spacing
Fasteners
Sealing or Applying a
Weather-Resistant Finish
Removing Sap
drying out process, the wood may experience varying
degrees of moisture, causing slight variations in thickness
and width (up to ½” in wider boards) between pieces of
wood. Generally speaking, this drying and shrinking does
not interfere with the construction process, but may
require some amount of planning to determine whether
possible shrinkage of the wood products will affect your
particular project. Exposing wood to the elements will
also cause swelling and shrinking. Allowing the boards
to acclimate or dry out some prior to construction may
be part of that plan. It is never recommended to plane
a piece of treated lumber to attempt to match the size
of another piece. If the deck boards are wet and swelled
with moisture (wider than 5½"), butt the boards tightly
together since they will shrink as moisture is released from
the wood. Conversely, if the wood is fairly dry and the
board measures approximately 5½" or less, gap the boards
to allow for future swelling from moisture absorbed into
the boards from natural elements. Gap the boards to
your desired width, the wider the gap the better. Gapping
allows for easy cleaning, dirt and leaves won’t plug up a
wider gap as easily. Wider gaps allow for greater air flow
which helps to cool the boards, lessening sap problems and
promotes faster drying, which helps prevent mold.
based stains can be applied after 6 months. Check that the
wood is surface dry before applying stain. In all instances
follow the manufacturer’s directions when applying water
repellents or semi-transparent stains which may contain
water repellent.
are designed for superior holding power and restraining
wood movement to limit twisting or warping. Use the
proper length of screw and when screwing close to ends
of boards, drill pilot holes to minimize cracking and splitting.
Lumber adhesive, PL-500 or similar, specically formulated
for treated lumber helps minimize cupping and warping by
providing a strong durable bond.