For over 100 years, light wood frame construction has been widespread in the United States because it is light, quick, renewable, easily customizable, and does not require heavy tools or equipment. However, contractors, architects, and building owners must contend with several significant problems associated with wood-frame construction.
1. High and Increasing Costs of Framing Lumber
The cost of framing lumber is reaching record highs. The spike in prices is primarily due to the tariffs on Canadian softwood timber that took effect in November 2017. Lumber prices have also been impacted by wildfires that have destroyed some timberland in British Columbia.
The random lengths framing lumber composite price reached a high of $582 in June 2018; a thirty percent increase over the average composite price in 2017. The National Association of Home Builders (NAHB) reports that framing lumber, including installation, accounts for around 18 percent of a home's average selling price. Consequently, according to Robert Dietz, chief economist for the NAHB, the tariff will increase the cost of a typical newly-built wood framed home by about $9000.
2. Moisture Problems with Wood-Frame Construction
Wood-frame buildings are susceptible to moisture in their wall cavities. Controlling moisture is challenging because effective methods that stop moisture from entering a wall cavity may also prevent the moisture from leaving the wall cavity. High humidity within a building's cavities is dangerous because moisture can cause wood rot and expensive repairs. High humidity can also lead to the growth of mold, which may cause asthmatic and allergic reactions for the occupants of a building.
3. Termite Problems with Wood-Framed Construction
Wood-frame construction is prone to termite problems. Termites can damage a structure’s integrity and cost thousands of dollars in repairs. In fact, the yearly estimated cost of termite damage and control measures in the United States is $5 billion. Applying termite protection during wood-frame construction is challenging and requires specialized equipment and a trained professional; however, it is essential for maintaining the durability of a wood-frame structure.
4. Disaster Resistance Problems with Wood-Frame Construction
It is challenging and expensive to construct a wood frame building that has the strength, durability, and resilience to resist storms, tornadoes, flooding, hurricanes, and earthquakes. In earthquake susceptible areas, anchoring a building to its foundation is critical to avoiding structural shifts and the threat of water seepage. In hurricane and tornado areas, contractors must follow strict building code standards for a continuous load path to the ground and ensure a minimum level of resistance to wind loads. Also, to prevent damage to the building’s envelope, the windows, walls, roofs, and doors must be missile resistant. Constructing a disaster resistant wood-framed building is doable; however, it can cost 25–30 percent more than standard construction.
5. Wood Frame Construction Lacks Thermal Mass
Wood has low thermal mass. Therefore, wood frame buildings are not as naturally energy-efficient as structures constructed with high thermal mass products like adobe, stone, and Bautex concrete blocks. High thermal mass materials draw in and store heat energy in the day and release the energy at night. The process slows the rate of heat transfer and helps stabilize temperature shifts within a building, which makes high thermal mass products an excellent choice for warm climates.
6. Waste Problems with Wood-Frame Construction
Wood-frame construction often requires a lot of shaping and resizing of the lumber. The process creates waste and financial loss to the client. However, wood waste generated by commercial and residential construction projects offers the potential for reuse and financial gain. Scraps and cut-offs generated during the trimming and framing constitute a clean waste that can make an excellent feedstock for engineered wood products. To lessen disposal costs and even generate income, builders should contact wood waste processors about setting up drop boxes on site for wood waste scraps.
7. Sound-Proofing Problems with Wood-Framed Buildings
Constructing a wood-framed building with adequate sound insulation is challenging. Solid and heavy concrete construction, like the Bautex Wall System, provide better noise and sound insulation than lightweight timber. There are several methods contractors can use to achieve sound reduction within wood-frame buildings, including doubling up on the plasterboard or replacing it with a heavier board like Fermacell.
8. Wood-Framed Construction is Susceptible to Fire Damage
Fire prevention and resistance are crucial and challenging tasks to builders of wood-framed structures. Wood-frame buildings are especially vulnerable to fire damage during construction before contractors have placed fire protection over the frame. The challenge to builders of wood-framed buildings is to stop fires and, in the event of a fire, restrict the spread of flames. Limiting the spread of fire is accomplished by cladding the frame in materials that resist heat and flames and treating the wood with fire retardants.
9. Swelling and Shrinkage of Wood Frame Construction
Wood swells or shrinks when it gains or loses moisture above or below its fiber saturation point of 28 percent. The fiber saturation point for wood is where all the wood fibers are fully saturated. Above the fiber saturation point, water starts to fill the wood cells. Decay begins if the wood is above the fiber saturation point for a length of time. If the wood is below its fiber saturation point, the wood will shrink. In three, four, and five-story buildings, the effects of shrinkage can affect the building envelope.
10. Wood-Frame Buildings May Compromise Indoor Air Quality
Wood-frame buildings may also contain volatile organic compounds (VOC), chemicals, and adhesives, all of which will compromise indoor air quality of a building or home. Emissions of VOCs are dangerous because they can cause eye, nose, and throat irritations. VOCs also cause nausea, headaches, and harm to the central nervous system, liver, and kidneys.
11. Limitations on Designs for Wood-Frame Construction
Limitations in architectural styles and elements are a problem with wood frame construction. With wood frame construction, it is difficult to include large and numerous windows, large spans, and cantilevers and in the design of a wood-framed building.
Make a Better Choice
Though wood-frame construction is highly popular, there are many considerations that might not make it the best choice for your building or home. Reviewing these tips and choosing a product like the Bautex Block System can save you time and money on your next project.