James Hardie Plank siding installation requires adherence to specific guidelines to ensure building envelope performance and maintain warranty coverage. These instructions detail critical aspects of the installation process, including substrate requirements, fastening techniques, joint treatment, and handling procedures. The documentation emphasizes the importance of consulting local building codes and utilizing appropriate safety measures during installation.
Substrate and Framing Requirements
James Hardie Plank siding can be installed over both braced wood and steel studs. Acceptable steel stud gauges range from a minimum of 20 gauge (33 mils) to a maximum of 16 gauge (54 mils), with a maximum stud spacing of 24 inches on center. Alternatively, the siding can be directly applied to a minimum of 7/16 inch thick OSB sheathing. Prior to installation, any irregularities in the framing or sheathing must be corrected to prevent mirroring through the finished siding application. Installation over non-nailable substrates, such as gypsum or foam, is addressed in James Hardie Technical Bulletin 19, available on the company’s website.
Water-Resistive Barrier Installation
A water-resistive barrier is required in accordance with local building code requirements. This barrier must be installed correctly, with appropriate penetration and junction flashing, to prevent water infiltration. James Hardie does not assume responsibility for water infiltration issues. The company manufactures HardieWrap® Weather Barrier, a non-woven, non-perforated housewrap that complies with building code requirements.
Siding Storage and Handling
Proper storage and handling of James Hardie Plank siding are crucial to prevent damage and ensure optimal performance. Planks should be stored flat, kept dry, and covered before installation. Installing wet or saturated siding may result in shrinkage at butt joints. When carrying planks, they should be carried on edge to protect the edges and corners from breakage. James Hardie is not responsible for damage caused by improper storage and handling.
Cutting Procedures
When cutting James Hardie Plank siding, it is recommended to position the cutting station so that airflow blows dust away from the user and others in the vicinity. The preferred cutting method is using a circular saw equipped with a HardieBlade® saw blade.
Fastening Requirements
When installing HardiePlank lap siding, nails should be placed 3/8 inch from the edge of the plank. The documentation specifies a maximum fastener spacing of 24 inches on center. A 1 1/4 inch starter strip should be installed to ensure a consistent plank angle. Fastening methods vary depending on whether the construction is a single or double wall application.
Joint Treatment Options
Joint treatment is required by code, as referenced in the 2009 IRC R703.10.2. Acceptable options include:
A. Joint Flashing (James Hardie recommended) B. Caulking (Caulking is not recommended)
Field painting over caulking may result in a noticeable sheen difference compared to field-painted PrimePlus siding.
Clearance Details
When installing James Hardie products, all clearance details outlined in figures 3-14 of the installation guide must be followed. Adjacent finished grade must slope away from the building in accordance with local building codes, typically a minimum of 6 inches in the first 10 feet.
Product Limitations
HardiePlank lap siding should not be used in fascia or trim applications. It is designed for installation on flat, vertical wall applications only. For larger projects, including commercial and multi-family projects with wall spans exceeding specified limits, contacting James Hardie technical support is recommended. The company provides installation and wind load information for buildings with a maximum mean roof height of 85 feet. Installations exceeding 60 feet in height require consultation with James Hardie technical support.
Moderate Contact at Butt Joints
The documentation illustrates that planks should be installed in moderate contact at butt joints, as depicted in Figure 2. This detail is important for proper siding alignment and weather resistance.
Available Product Styles
James Hardie Plank siding is available in several styles, including Select Cedarmill®, Smooth, and variations of beaded and colonial styles. These options provide aesthetic choices for different architectural designs.
Important Considerations
The documentation stresses the importance of confirming the use of the correct HardieZone® product instructions by visiting HardieZone.com or calling 1-866-942-7343 (866-9-HARDIE). Failure to follow James Hardie written installation instructions and comply with applicable building codes may violate local laws, affect building envelope performance, and may affect warranty coverage. Additionally, failure to comply with all health and safety regulations when cutting and installing this product may result in personal injury.
Conclusion
Proper installation of James Hardie Plank siding is critical for ensuring long-term performance, maintaining warranty coverage, and adhering to local building codes. The guidelines emphasize the importance of correct substrate preparation, appropriate fastening techniques, proper joint treatment, and careful handling of the siding materials. Consulting the complete installation instructions and technical documentation available on the James Hardie website is essential for a successful installation.