Prevent These 4 Common Problems with Wood Construction
Wondering why the wooden boards in your construction project are swelling? Getting calls from clients about damage to their homes?
It’s frustrating to work hard on a wood construction project only for it to become damaged by the elements.
And these problems often don’t occur until after you’ve left the jobsite.
Thankfully, with some proactive steps, you can make it less likely to have to deal with those problems at all. Follow along as we explain:
- Common problems with wood in construction
- Why it’s still worth using wood
- How to prevent problems with wood construction
Let’s roll up our sleeves and get started!
What are some common problems with wood in construction?
Wood is a sensitive construction material, largely due to the fact that it’s organic. Unlike synthetic materials, it can rot and decay or be broken down by wood-infesting insects like termites.
There’s also the fact that wood is hygroscopic, or affected by changes in temperature and humidity. This means it’ll release or absorb moisture, swelling, shrinking, or warping in the process.
And the problems aren’t just cosmetic; they could also cause intense structural damage over time.
The first sign of wood damage doesn’t mean your project is done for, though. Most problems can be solved if you take action soon enough.
Here’s how to prevent and deal with the four most common problems in wood construction.
1. Expansion and contraction
When the moisture levels of wood change, the wood can expand or contract. This means timber buildings are especially sensitive to drastic changes in moisture or temperature.
Expansion happens when wood swells and warps from absorbing moisture. Contraction happens when the wood releases its moisture and dries enough to shrink in size, which can often lead to gaps between wooden slats.
While wood will naturally expand and contract no matter what you do, you can decrease the amount of warping and gaps in your wood by covering it with tarps to protect it from rainwater.
You can also protect the interior of your wooden structure from high moisture levels by maintaining stable moisture conditions. Use dehumidifiers to keep indoor areas between 30 and 50% relative humidity, and set your thermostat between 65 and 75° F for optimal environmental conditions.
The sooner the humidity is regulated, the sooner your boards will acclimate to the moisture in the air. This allows expanded boards to contract, and contracted boards to expand. Though it doesn’t always fix all the damage, acclimating your boards can help relieve cupping, buckling, or warping problems.
2. Decay and rot
Decay and rot can also be caused by high moisture levels that persist over time. When moisture seeps into wood, it causes the wood fibers to break down. This may then cause discolored wood, musty smells,1 flaking wood, or peeling paint.2
Of course, no one wants their wood flooring, wood sheathing, or wood beams to rot, but it can be especially hazardous when it occurs in structural supports like joists or wood studs.
Protect your project from decay by making sure your structure is built to withstand rainy weather. You can do this by properly installing rain gutters and carefully sealing windows.
Called in to fix up an old construction project?
If you’re just seeing superficial damage in siding or window sills, dry the wood out, chip away the decayed parts, apply epoxy consolidant to strengthen the remaining wood, and use epoxy filler to fill in the gaps.3 When you’re all finished with the repairs, sand and stain or paint it to restore its original appearance.
3. Insect infestation
Termites can eat away at wood fibers, making holes and tunnels in beams or floors. The main way to protect a construction project from future termite damage is by spraying insecticide directly on the wood in question.4
You may also want to spray it around the perimeter of the project, particularly in areas where soil or plants are pressed up against the side of the house.
If you’re called in to repair a house with termite damage, keep in mind that small amounts of wood damage can usually be fixed by using wood fillers or hardeners.5 But if you have a lot of wood damage, you might want to reinforce certain areas of the house.
If the wood you’re dealing with is a structural component, place a steel or wooden beam beneath the weak beam to help support it. Working with wooden floors or walls? Reinforce them by applying wood hardener or wood filler.6
If you see the wood in the home is falling apart or sounding hollow when you tap on it, you’ll want to replace the damaged wood entirely (after the homeowner has called pest control to deal with the infestation).
4. Creeping and splitting
Creeping and splitting can happen when your wood is adjusting to varying moisture levels and temperatures.
Wood can naturally get small cracks or splits while it’s acclimating to its environment,7 and many splits and cracks shrink and become less noticeable over time as the wood acclimates to changing moisture conditions. But drastic cracking or splitting that doesn’t subside over time might indicate more serious structural damage.
If you notice these problems while you’re working on a project, you can attempt to acclimate the wood by exposing it to dehumidifiers like you’d do for cupping wood.
But if you’re dealing with a serious split, use wood glue or wood epoxy to fill in the crack and hold the wood together.8
Meanwhile, wood creep deflection, or creeping, is a type of wood deformation seen in structural supports that can happen when moisture changes cause wood to stretch and sag under the weight the wood supports.9
Though some amount of creeping is normal, building codes typically define how much creep is acceptable, depending on where the creep is occurring and how large your structure is:
“Generally, for roof trusses, the deflection in inches due to live load cannot exceed the span in inches divided by 240 (L/240) and due to total load L/180. For floor trusses, the deflection in inches due to live load cannot exceed the span in inches divided by 360 (L/360) and due to total load L/240.”10
One of the most common ways to fix creeping wood is by reinforcing it with another piece of wood, or steel.11 You can help prevent creeping issues by ensuring the wood is well-acclimated and that you’re using an appropriately sized piece of wood for the weight you want it to support.
Though wood is susceptible to a variety of issues, the benefits of using wood can make repairs well-worth the cost.
Is wood still worth using in construction?
Wood is a great building material because it’s:
- Relatively light
- Strong
- Energy-efficient
- Natural
On top of having these benefits, wood is known for its sustainability. It’s a renewable resource because its production releases less carbon emissions than the creation of other materials.12
Wood is also known for maintaining its warmth and helping a home look beautiful and inviting.13 (Especially compared to cold, hard steel.)
Of course, some types of wood are better suited to construction than others.
These include wood species like:14
- Spruce
- Pine
- Cedar
- Fir
In some instances, wood can be more damage-resistant than steel or concrete.
Even though wood products might be more flammable than metal or concrete, they have the advantage of burning at an even rate no matter the temperature, unlike steel which could collapse in moments if exposed to very high temperatures.15
There’s also the fact that wood can be covered in different substances to increase its fire resistance and protect it from moisture or insects.
If you decide, though, that you’re not interested in using wood in your construction projects, here are some alternatives to consider.
What are some alternatives to wood materials?
Common alternatives to wood materials are16:
- Concrete
- Stone
- Steel
These materials, along with engineered wood products like oriented strand board (OSB)17 and cross-laminated timber (CLT)18 are known in the construction industry for their durability.
Stone, steel, and concrete are also known to be more fire and moisture resistant than wood.
Not to mention, you’ll never have to worry about any insects trying to eat any of these materials away!
Of course, as you consider what material to use, it’s important to remember that every material has its pros and cons.
While steel is strong, it lacks the self-supporting capabilities of wood, meaning it requires a lot more structural support to keep it held up. And while concrete does a better job of blocking out sound than wood, sounds echo more within a concrete structure than a wooden one.19
But if you’re only worried about using wood because you’re afraid it will be impacted by moisture or infestation, there are relatively easy ways to prevent those issues from happening in the first place.
How to prevent problems with wood in construction
Follow these practices to help your wood construction stand the test of time:
- Maintain proper moisture conditions:
Many of the issues in wood construction occur when the wood is exposed to high moisture levels. This can be especially damaging if the wood didn’t acclimate to its environment. Unacclimated wood is more likely to change in size and shape, which can spell disaster if it’s already been installed with fasteners or nailed in place.
To minimize the damage caused by moisture, maintain a consistent temperature and moisture level inside a wooden building.
And though there’s nothing you can do to regulate the environmental conditions of the outdoors, you can apply sealant to your wall sidings and install rain gutters to protect your walls from the rain.
- Protect wood with sprays:
Protect the wood from insects and fires by using insecticides and fire retardant spray. - Address water infiltration zones:
Look for problem areas like cracks, window sills, and doors, and plug in any gaps to keep moisture from entering the home. - Don’t delay in making repairs:
Try to repair any damage you notice as soon as possible. This can help keep small issues and damage from growing into larger issues and more expensive repairs.
While all of these practices can help prevent wood damage, one of the most crucial things you can do is monitor the moisture content of your wood during construction.
After all, moisture accounts for most of the problems in timber construction.
That’s where a moisture meter comes in!
Use a handheld wood moisture meter to monitor the moisture levels of your wood, helping you determine when the wood has acclimated and whether it’s on the verge of developing any moisture-related issues.
Taking these preventative measures and monitoring the wood during construction is an essential part of protecting the structure from future harm.
To get a tool that can help you identify your moisture-related problems, visit our shop for some easy-to-use wood moisture meters.
New to the world of wood moisture testing?
Find out what your moisture meter readings mean for your project by
- “The 5 Most Common Signs of Rotten Wood,” Brazilian Lumber. (↑)
- “How to Spot the Signs of Rotting Wood,” Nash Painting. (↑)
- Wallender, Lee, “How to Repair Rotted Wood,” The Spruce. (↑)
- “How to Get Rid of Termites,” Home Depot. (↑)
- Johnstone, Gemma, “How to Fix Termite Damage: A Complete Guide to Repairs,” Angi. (↑)
- Deziel, Chris, “How to Strengthen Wood,” Home Steady. (↑)
- “Lumber 101: How to Avoid Checking and Cracking,” CarlWood Lumber Limited. (↑)
- “A Complete Guide on How to Fix Split Wood,” Tallest Tree. (↑)
- “Creep Deflection in Structural Wood Beam Design,” Clear Calcs. (↑)
- “Truss Deflection,” Mitek, p.1. (↑)
- Bennett, Noah, “How to Fix Sagging Ceiling Joists,” Storables. (↑)
- “How sustainable is wood?” Thermory. (↑)
- “How Woodwork Adds Warmth to Your Home,” Oberer Residential Construction. (↑)
- Wood, Holly, “Best Types of Building Wood For Construction,” Materials Market. (↑)
- “How does timber handle fire compared to steel and concrete?” International Timber. (↑)
- “5 Excellent Alternative Materials for Wood in Construction,” Building Product Advisor. (↑)
- “OSB: A Durable & Eco-friendly Building Material that Increases Home Performance,” Tilson Homes. (↑)
- Moore, Andrew, “5 Benefits of Building with Cross-Laminated Timber,” NC State University. (↑)
- Lu, Sally, “Concrete vs. wood: Which is more soundproof?” Acuslat. (↑)