Cypress is a superior exterior siding material that offers natural beauty, with a rich grain, texture, and color that complements any architectural style. A naturally occurring preservative called cypressene makes cypress extremely decay, rot, and insect resistant. Cypress typically requires less repair and maintenance because of natural weathering, durability, cracking, and stability characteristics.
Before we begin, please note that these instructions may be more restrictive than local building codes, but local building codes must be followed in instances when they are more stringent. Cypress is manufactured to perform under ordinary service conditions when stored properly, installed on structures with proper vapor retarders and ventilation, and finished and maintained in accordance with the following instructions.
Cypress siding is a quality wood product dried in accordance to the Standard Specifications for Grades of Southern Cypress. Finish grades contain a maximum moisture content of 15%, whereas Common grades contain a maximum of 18%.
Before installation, store cypress in an area that is undercover, dry and well-ventilated so that it achieves its in-service moisture content.
Apply a finish to all surfaces, including ends. Factory applied finishes are best.
In addition, walls should be designed with a vapor barrier, such as 6 mil polyethylene or foil-backed insulation to prevent moisture vapor from within the exterior wall cavity.
Install cypress siding over standard sheathing material, such as building felt paper or a water-repellent wind barrier, with maximum stud spacing of 16 on-center.
Two types of nails are commonly used with siding: finishing nails and siding nails.
In this demonstration, we are using stainless steel siding nails with a ¼-inch head, long enough to penetrate 1-½ inches into studs, with a blunt point to reduce splitting of the siding. Remember to account for sheathing material when determining nail length. Ring shank or thread shank nails will provide increased holding power but must penetrate studs at least 1 inch.
For caulking, we suggest a high-grade, non-hardening acrylic to seal gaps around windows, doors, corners, and other exterior joints.
Please note that drip caps and flashing must be used over doors, windows, masonry, other types of siding, and siding returns at dormers.
Corner Boards must be used at inside and outside corners. They come in several sizes, depending on the thickness of the siding. Interior corner boards must be square.
To install bevel siding, begin by determining the lap. The minimum lap for bevel siding should not be less than 1 inch.
For weather resistance and appearance, the butt edge of the first course of siding should coincide with the top of the window drip cap. The bottom of a siding course should be flush with the underside of the window sill.
Begin installing the siding with the bottom course, blocked out with a starting strip the same thickness as the top of the siding board.
Each succeeding course will overlap the upper edge of the lower course.
Nail the siding to each stud or on 16-inch centers, approximately 1/8 above the overlap to allow for slight movement of the siding due to moisture change.
Avoid butt joints wherever possible. Use longer sections for long stretches, like under windows and shorter lengths for areas between windows and doors. When necessary, always make butt joints over a stud, and staggered between courses as much as possible.
Square cut the siding to provide a good joint at window and door casings and at butt joints, to prevent moisture penetration. Dip fresh-cut ends of siding in a water-repellent preservative before boards are nailed in place.
Before finishing, repair all nail holes and surface irregularities. All surfaces should be clean and caulking should be in good condition. Seasoned cypress siding should be finished promptly at the time of installation to protect against moisture absorption, discoloration from rain, and mildew. However, under no circumstance should siding be finished when it is wet.
For complete installation guidelines and proper design, storage, application, finishing, and maintenance of cypress siding, please visit www.cypressinfo.org.