Installation Guide
5 
K.  CORN
ERS FASCIA & RAKE BOARDS 
SECURE PIECES PROPERLY When framing members (rafters, outlookers, etc.) are not located 
where Primed Trim Board
 pieces join, install 1-1/4” solid blocking first and then nail the Trim to it. 
Fasten from the face of one Trim member into the edge of another by pre-drilling pilot holes and 
inserting stainless steel wood screws. 
L.  CLEARANCE 
REMEMBER: 8, 2, ¼ Water table or skirt boards and corner boards must be a minimum of 8” to 9” 
above the finish grade. Trim that extends down to a roof (dormers, second floors, etc.) and decks 
requires a minimum 2” gap to avoid wicking. Flashing is imperative, but maintain a 1/4” gap for a 
capillary break. 
M. FLASHING AT OPENINGS & HORIZONTAL PROFILES 
Proper flashing is imperative. Flashing is an important line of defense against water in wall 
assemblies. Use flashing to intercept and direct the flow of water away from the building to designed 
drainage paths. Install horizontal flashing extending from the top of all windows and doors and where 
there is any change in material or direction. The flashing should tilt downward (~30o) to allow water 
to drain away from the wall. Do not caulk where the flashing and Trim or other materials meet. Note 
that caulking in lieu of flashing is not acceptable. 
N.  CAULKING 
TYPE: Use exterior grade high-performance acrylic-latex, silicone, acrylic, or urethane caulks and 
sealants to seal gaps around windows, doors, corners, and other joints that are exposed to potential 
water intrusion. 
REQUIRES MAINTENANCE: Caulking is not a permanent solution and as such requires regular 
maintenance. If not inspected and maintained, caulking may fail and trap water, creating severe water 
problems. Do not rely on it as the only barrier to water penetration. Do not caulk areas that will 
prevent water from escaping the wall cavity (e.g., under windows and around flashing). 
AVOID 3-SIDED ADHESION. The caulk should only adhere to the two surfaces that create the 
opening in the surface plane, not to any rigid substrate behind. For gaps wider than 1/4 inch, insert a 
backer rod into gaps where caulk seals are to be made, and then caulk over. In all cases, follow the 
caulking manufacturer’s recommendations. 
O.  DECK & COLUMN WRAPS 
When using Primed Trim to face 
building materials such as treated lumber, structural beams and 
posts, or any framing material, always apply housewrap before installing any finishing material. 
Where Primed Trim Boards are used to finish rim joists, protect the top edge from water intrusion by 
applying a strip of self-adhesive membrane over the rim joist and Primed Trim Board. It is important 
that water not pool between the framing lumber and the decorative Primed Trim Boards. 
Incorp
orate an air cavity.  Columns wrapped in Primed Trim Boards must be constructed to 
incorporate an air cavity between the Primed Trim Boards and the underlying core. Ventilation 
and drain holes must be included at the top and bottom to ensure proper airflow and drainage. 
P.  PRIME ALL CUTS 










