Wood Floors and Electric Radiant Heat
Choosing Wood Flooring: Rift and Quartered Sawn Oak
Extensive laboratory testing by Launstein Hardwood Floors in Mason, Mich., found that American hardwoods – including cherry, oak, ash, maple, hickory, and walnut – are good choices for radiant-heat flooring. Beech, Australian cypress, and many bamboo products are examples of those that are not.
We wanted to purchase and install a material that would not only match the existing oak strip flooring, but be dimensionally more stable with the added floor heat. It’s natural for all floors to shrink and swell, depending on the season, so we chose rift and quartered oak which is touted as approximately 30 percent more stable than plain sawn oak flooring.
Rift and quartered boards rival engineered flooring. These boards will only expand / shrink in thickness (height) and will remain stable from side-to-side (width). They are perhaps the best option for wood floors and electric radiant heat, and also an excellent choice to minimize seasonal gaps, buckling, and so on.
Tips for Choosing Wood Flooring:
Whether your installing a Warmup electric radiant heat under wood floors or any other brand you will want to make good decisions on your flooring choice. Here are some suggestions for choosing wood flooring:
- For best results with wood floors and electric radiant heat, use narrow boards, preferably not wider than 3 inches. Narrow boards will better accommodate wood’s natural expansion and contraction across a floor.
- Use quarter-sawn wood for planks wider than 3 inches, for better dimensional stability.
- Acclimate your wood floor: Wood naturally expands and contracts to reach balance with the relative humidity of its surroundings. Avoid installing wood flooring when moisture levels are high, such as during painting or the installation of plaster.
- Before hardwood floor installation, operate the heating system until the relative temperature and humidity in the space stabilizes to the average level expected for seasonal conditions in the area in which the wood floor will be installed.
- Ensure your flooring’s moisture content is appropriate for your area. Typically, a 6-to-8 percent moisture content is average.
- Engineered floors are inherently more stable.
- Reclaimed woods typically have tighter growth rings (since the wood is more likely to be old-growth) making them denser and more stable.
- Parquet: Overall, parquet floors have less expansion and contraction.
- Dark floors: Their color makes gaps between boards less obvious.
- Flooring with beveled edges make any gaps less obvious.
Wood Floor Installation
First, deliver the flooring about 1.5 weeks early to let it acclimate to the conditions in the house.
TIP: Your final installation is only as good as the sub-floor you’re installing over. Carefully inspect the sub floor and fix any problems that could affect your installation. We like to add screws thru the sub-floor and into the floor joists to help eliminate loose floor boards and potential squeaks.
Installing the oak boards is the same as it would be without radiant heat; all the precautions recommended for strip flooring apply. When installing the Warmup electric heat under wood floors, you need to slow down and be precise in placing 1-1/2″ or 2″ fasteners. We blind fastener spacing along the length of the sleeper strips, minimum 2 fasteners per piece near the ends (1”-3”).
TIP: Use construction adhesive and fasten your sleeper strips to the sub-floor, you want to ensure that your sleeper will not pull up off the sub-floor. This especially becomes important when the sleepers are thick, [1/2″ or 3/4″ thick] and the hardwood floor fasteners may not long enough to penetrate thru the sleeper and into the sub-floor.