Wood siding installation & product guide: this article provides details for proper installation of wood building siding materials. This article series discusses best practices construction details for building exteriors, including water and air barriers, building flashing products & installation, wood siding material choices & installation, vinyl siding, stucco exteriors, building trim, exterior caulks and sealants, exterior building adhesives, and choices and application of exterior finishes on buildings: paints, stains.
Green links show where you are. © Copyright 2015 InspectApedia.com, All Rights Reserved.
This article series includes excerpts or adaptations from Best Practices Guide to Residential Construction, by Steven Bliss, courtesy of Wiley & Sons. Also see FLASHING WALL DETAILS and FLASHING ROOF WALL DETAILS and also RAIN SPLASH-UP SIDING DAMAGE.
While the premium grades of siding are more forgiving of installation and finishing problems than budget materials, all wood siding requires attention to detail to provide a durable and attractive exterior. Critical details are backpriming, air space, nailing, and finishing.
An air space behind the siding, in addition to protecting the building shell (see “Rain-Screen Principle,” page 2), also improves the performance of wood sidings. The siding material is less prone to moisture movement and paint is less likely to fail, even if the space is only 1/4 inch wide.
While the vast majority of wood siding is installed directly on the sheathing wrap, builders who have had problems with paint and siding have found that adding an air space is worth the additional cost. New products— such as wrinkled and corrugated sheathing wraps with an integral air space, and behind-the-wall drainage mats such as Benjamin Obdyke’s Home Slicker®—are simplifying this step.
The major trade associations representing siding manufacturers all recommend back-priming and priming of cut ends. With cedar and redwood, backpriming will minimize the bleeding of extractives from the back of the siding, which can drip onto the face of the siding and stain the finish, and can also degrade sheathing wraps. With all sidings, back-priming will reduce the movement of moisture into and out of the siding, minimizing problems with cupping, warping, and checking.
The need for back-priming and a ventilation air space is even greater when installing over foam sheathing. With no air space and no wood sheathing to temporarily store the moisture, any water that leaks through the siding or is driven in by the sun will tend to wet the back of the siding. The result, documented in a joint study conducted by wood siding and foam manufacturers, is increased cupping, cracking, and paint problems.
Nailing requirements are shown in Table 1-3 below. In general, nails should penetrate the sheathing and studs or blocking by 1-1/2 inches, or 1-1/4 inches with ringshank or spiral-shank nails. Although specialized siding nails with small heads and blunt tips are preferred, staples are acceptable for some applications.
Since the cost of fasteners is a small percentage of a siding job, it makes sense to use stainless steel, particularly with cedar and redwood, which can react with some types of fasteners. The most common fastener choices are as follows:
These are corrosion resistant and can be used with all wood sidings. However, the aluminum can react with galvanized steel flashing and cause corrosion Hot-dipped galvanized. These can react with the tannins in cedar and redwood, causing black stains and streaking. Also the protective coating can chip when nailed, exposing the underlying steel to corrosion.
These are not recommended for any siding application since the coating is not thick enough and they are likely to corrode and stain the siding.
In general, vertical sidings are nailed to the top and bottom plates and to horizontal nailers installed every 36 inches for face-nailed siding and every 32 inches when blind-nailed. Because vertical sidings are vulnerable to leakage, they are not recommended for areas subject to wind-blown rain.
Plywood siding is often nailed directly to studs or through an insulating sheathing and serves as a structural sheathing as well as the exterior finish. Use 6d box, siding, or casing nails for nominal 1/2-inch plywood siding nailed directly to studs. For nail spacings, see Table 1-4 below.
-- Adapted with permission from Best Practices Guide to Residential Construction.
Frequently Asked Questions (FAQs)
No FAQs have been posted for this page. Try the search box below or CONTACT US by email if you cannot find the answer you need at InspectApedia.
Questions & answers or comments about how to install wood siding, clapboards, etc..
Use the "Click to Show or Hide FAQs" link just above to see recently-posted questions, comments, replies, try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.
Search the InspectApedia website
HTML Comment Box is loading comments...
Technical Reviewers & References