Hardwood floors and moisture have a complex relationship. Too much moisture can cause the boards to warp; however, too little moisture can cause them to fracture.
Fortunately, there are steps you can take prior to installation that can help mitigate the effects moisture can have on the flooring in your client’s home.
We’ll cover these steps in the first part of this 3-part series, all about hardwood vs. moisture.
Handling and Storage
Long before installation begins, you need to consider how the boards are being handled and stored. There are many opportunities during this stage for hardwood floorboards to come in contact with moisture from the atmosphere. Ask the retailer whether cartons have been properly unloaded and stored in dry conditions.
Also, pay attention to the climate of your storage location. Humid climates have a lot of moisture in the air, which can cause the boards to expand.
To prevent this, leave adequate room for good air circulation around stacks of flooring and avoid storing hardwood floors in a humid area.
If the boards expand prior to installation, they’ll likely contract again once installed indoors, where there’s more climate control. This contraction can cause cracks or gaps between the boards.
Not only are cracks and gaps unsightly; however, they can also be a tripping hazard for toddlers or aging residents.
Preparing to install hardwood flooring is all about preparing your jobsite. It’s important that conditions are as free as possible from excess moisture to avoid floorboard expansion. You’ll want to keep relative humidity levels between 30-50%.
The building you’re constructing must be structurally complete, enclosed, and sealed off from rain and snow. All finished wall coverings, painting, masonry, and drywall installation also need to be complete and dry, to avoid raising moisture levels in the building.
Other measures you can take to reduce or prevent excess moisture, include:
- Running the HVAC system for seven full days prior to installation
- Maintain a consistent room temperature of 60-75˚ Fahrenheit
- Ensure basements and crawl spaces are dry, by installing a vapor barrier
- Check subfloors for moisture content, using a metering device
- Use a moisture meter to monitor the flooring and jobsite conditions, as the flooring acclimates
While natural hardwood needs ample time to acclimate before installation, engineered hardwood flooring from Landmark Interiors is typically ready to install upon delivery. This is true in most normal environments, where the temperature is kept between 60-70˚ Fahrenheit.
Finally, prepare the subfloor before installing hardwood floors. What you need to do to prepare will depend on the kind of subfloor you’re dealing with.
For a wood subfloor, check first that it’s dry and free of wax, paint, and oil. The subfloor shouldn’t exceed 12% moisture content. If it exceeds this amount, or if any of the underlayment or subflooring is water-damaged, all or part of it may need to be replaced.
Use an in situ relative humidity (RH) probe to measure the relative humidity. It should be below 75%. The in situ RH test is preferred by the flooring installation experts at Landmark Interiors.
Alternatively, you can check the moisture content of the concrete slab using a TRAMEX concrete moisture meter. If the moisture content is at 4.5% or more, additional repairs and tests are needed.
Engineered Hardwood vs Natural Hardwood vs Moisture
If your client wants the classic look of hardwood, but you’re concerned about moisture, consider engineered hardwood. This kind of flooring layers a thin layer of hardwood on top of a plywood or fiberboard core—improving durability and moisture resistance.
In general, plywood and fiberboard can handle much more moisture than natural hardwood, which can reduce some of the issues you may experience or plan for during the pre-installation phase.
You’ll still want to follow the manufacturer’s instructions to determine proper pre-installation storage and jobsite conditions.
Make Moisture Control Part of Your Pre-Installation Process
Moisture control is a vitally important part of the pre-installation process when planning to lay hardwood flooring in a client’s home. This’ll continue throughout the entirety of the installation process and after, which we’ll cover in future installments.
If you have any additional questions about the proper handling of hardwood to prevent moisture, contact Fishman Flooring Solutions, or check back in a couple of weeks while we continue to walk through tips for managing moisture levels on your jobsite.