LP SmartSide Lap Panel Instruction Manual

Technical Note No. 070
LP® SmartSide® and LP® SmartSide® ExpertFinish® Panel Siding Installed over Furring without WRB
on Concrete or Masonry Walls

This Technical Note is an addendum to the LP® SmartSide® and LP® SmartSide® ExpertFinish® Panel Siding Application Instructions (“Instructions”). It is intended to provide an alternative fastening option for panel siding over furring strips without a water-resistive barrier (WRB) on concrete or masonry walls. The Instructions remain effective except as may be modified by this Note. Refer to the Application Instructions for all other aspects of product installation.

Contents hide

1 Panel siding attached to furring strips:

2 Limitations of Use:

3 Fastener placement:

4 Documents / Resources

4.1 References

Panel siding attached to furring strips:

Siding must be installed over a min. 3/4″x 3-1/2” (19 mm by 89 mm) actual size, preservative-treated furring, spaced no more than 16” o.c. (400 mm) in wind speed areas less than or equal to 140 MPH, Exposure C (Maximum Design Pressure 34).

Minimum Fastener Type:
o Corrosion Resistant = hot-dip galvanized (ASTM A153, Class D) or equivalent; capable of preventing rust, stain and deterioration under normal outdoor environmental conditions for a period of no less than 50 years.
o Ring Shank
o Shank diameter = see Table 1
o Length = fastener shall fully penetrate a min. 1/2 inch (13 mm) into nailable furring. Caution: fastener shall not bottom out on concrete or masonry wall leaving the fastener head less than flush with the face of trim or siding. (Figures 1)
The IRC and Florida Building Code, Residential require a WRB be used behind the exterior cladding, except over concrete or masonry walls per Exception 1 in Section R703.1.1.

Current building science practices recommend ventilation at top & bottom of wall.
o Openings at the top and the bottom of the wall should be open to the outside air and protected with insect screen. (Figures 6 & 8)
o Check with local building codes for additional requirements.
Siding shall be installed to safely resist all loads, including wind loads, of the locally adopted building codes. The installation of siding shall result in a system that provides a load path that meets the requirements for the transfer of loads from the point of origin through the load-resisting elements to the structure. The mechanical connection of the furring strips to structure is the responsibility of a design professional. LP assumes no liability for any loss or damage caused by the design of the mechanical connection of the furring strips to the structure and is expressly released by the purchaser or owner from any such loss or liability. For complete warranty details visit LPCorp.com/Literature.

Limitations of Use:

For use on concrete or masonry walls.
Panel siding cannot be used for lateral bracing.
Attaching panel siding to furring strips per Table 1:

Table 1
140 mph wind speed / Exposure C / Maximum Design Pressure 34 psf

Fastener Diameter (ring shank)	Fastener Spacing (inches o.c.)	Total fasteners 4’x 8’ panel (1 234 mm x 2.4 m)	Fasteners per furring strip*	Total fasteners4’x 9’ panel (1 234 mm x 2.7 m)	Fasteners per furring strip*	Total fasteners4’x 10’ panel (1 234 mm x 3.0 m)	Fasteners per furring strip*
0.120	6	68	17	76	19	84	21

Footnote: *Min. 3/4” x 3-1/2” (19 mm x 89 mm) preservative-treated furring strip with specific gravity of 0.55

Nail Condition and Correction Guidelines:
LP® SmartSide® ExpertFinish® Panel Siding

Painting all exposed nail heads is recommended.
Do not overdrive nails.
o Nail head should seat snug to face of cladding, but not be flush to distort the siding surface. (Figure 2)

LP® SmartSide® Panel Siding (Primed)

Caulk exposed nail heads where recommended. (Figure 3)
Do not overdrive nails.
o Nail head should seat snug to face of cladding, but not be flush to distort the siding surface. (Figure 3)