Wood Plank Sheathing

Environmental Impact Rating

Harvesting — Negligible to High

A wide variety of forestry practices are used to harvest wood cladding. At best, impacts are kept to a minimum, but at worst can include habitat destruction, resource depletion, soil erosion and silting and contamination of waterways. Third-party certification can help to ensure that impacts are minimized.

Manufacturing — Negligible to Low

Most wood cladding is milled to maximize the potential of each log. There can be as few as one step (rough sawing) and as many as four steps (rough sawing, planing and several steps to mill a profile) to the process, depending on the type of profile and finish being applied.

Transportation — Negligible to High

Sample building uses 1,395 kg of wood siding:

2.1 MJ per km by 15 ton truck

1.3 MJ per km by 35 ton truck

As a heavy material, wood will have significant transportation impacts if it travels long distances.

Installation — Negligible

Waste: moderate to high

Compostable — Untreated wood scrap. Quantity may be low or high depending on the application.

Recyclable — Metal fasteners. Quantity will be low.

Landfill — Pre-finished wood scrap.

Chart of Embodied energy & carbon

Energy Efficiency

Wood sheathing or cladding will not have a large impact on energy efficiency. When used as structural sheathing, the gaps between planks will require the use of a sheet-style air control layer to properly prevent air migration into the wall.

Material costs: Low to high

There are many types of wood siding and sheathing, from low-cost, rough-cut overlapping options to planed, tongue-and-groove options. Species can vary regionally, which also affects costs. Wood siding is one of the most wide-ranging options in terms of material costs.

Labour Input: moderate to High

The type, quantity and direction of strapping will have a large impact on labor input. Most styles of wood cladding have similar labor inputs for installation. If the wood cladding is being finished on-site, this will add significant time prior to the installation process.

Health Warning

Avoid breathing sawdust during cutting.

Skill level required for homeowners

Preparation of substrate — Easy to Moderate

A homeowner with basic carpentry tools and experience can apply a single or double layer of strapping.

Installation of sheathing — Easy to Moderate

A homeowner with basic carpentry tools and experience can apply a wood sheathing/cladding. A good installation requires an understanding of how the cladding is managed at corners and intersections. Trim work for some wood claddings can be moderately difficult.

Finishing of sheathing — Easy

Pre-finished siding requires all cut ends to be painted with the same finish. If wood cladding is unfinished, applying treatment is straightforward but can be time-consuming. Raw wood cladding requires no additional finishing time.

Sourcing & availability: Easy

Wood cladding is widely available in many styles from building supply outlets and specialty siding shops.

Durability: moderate

Raw wood lasts a long time as a cladding if installed properly. It can take seventy-five to a hundred years for raw wood to deteriorate to the point where it is no longer useful, with UV radiation being the most potent agent of decay.

Durability issues are more likely to be caused by finishes and the difficulties involved in refinishing. Paint, especially when applied only to the exterior face of the wood, will often crack and peel, requiring labor-intensive scraping and sanding to refinish. Stains, mineral treatments and washes will fade over time but will not be prone to the same cracking and peeling as paint. Deteriorating finishes will often cause a homeowner to remove and replace wood siding that feasibly had many more years of service life, so choosing a good finish and applying it to all six sides will go a long way toward extending the serviceable lifespan of wood cladding.

Wood cladding can also cup and warp, becoming visually unappealing. This is often due to improper fastening and/or finishing of the wood, and can be avoided by proper installation.

Code compliance

Wood cladding is an acceptable solution in all codes. Regions with termites may have restrictions or regulations to avoid infestation.

Indoor air quality: n/a

Resources for further research

Ireton, Kevin. Exterior Siding, Trim, and Finishes. Newtown, CT: Taunton, 2004. Print.

DeKorne, Clayton. The Essential Guide to Exteriors. Washington, D.C.: Hanley Wood, 2005. Print.

Brumbaugh, James E., and John Leeke. Complete Siding Handbook: Installation, Maintenance, Repair. New York: Macmillan, 1992. Print.

Future development

The growth of third-party certification programs is increasing the availability of sustainably harvested wood products, including cladding. Nontoxic finishes are also becoming more widely available.