How to pick the right underlayment
Transcription: You’ve picked your flooring style, now it is time to fill in the gaps for the other pieces to the project. Let’s talk about underlayments and how do you pick the right one for the job!? When choosing a flooring underlayment, not all are created equal. In fact, not all are universal for the type of subfloor you have. While concrete subfloors at or below grade have the potential for moisture emissions, most wood subfloors above grade are just the opposite. In general, work from the bottom side up first…Always understand what your subfloor is and address it’s needs first before picking out the underlayment for your flooring.
Concrete subfloors are porous and no matter how old the slab has been around, they are always emitting moisture vapor. Some concrete subfloors will emit more moisture than others and this depends on many environmental and geographical factors and water table conditions where the construction is located.
Concrete with qualifying moisture generally releases it as a vapor. It remains a vapor until it encounters an obstacle that causes it to form droplets or liquid. There are ways to test concrete moisture levels, check out the links in the notes to our other information and videos on that. But in general, when planning to install a flooring material over concrete, a proper vapor barrier is required in order to keep harmful moisture from damaging the overlying floor. Make certain your choice of underlayment lowers the rate of water vapor transmissions to an acceptable rate to protect the flooring choice.
New wood construction can sometimes be inundated with moisture from inclement weather prior to getting roofing materials on. Saturated subfloors need time to dry before placing the flooring on top of them. Likewise, wood subfloors over an unfinished crawl space are subject to moisture, therefore make certain the underlayment choice does not trap moisture in a wood subfloor but allows it to safely dissipate. If you are installing over a conditioned room below on a second story where moisture isn’t a cause for any of the mentioned concerns, then finding an underlayment with little to no moisture protection is fine.
After understanding any moisture concern the subfloor brings to the project, other considerations for picking out the right underlayment comes down to aesthetics and performance attributes that might be important for the living environment the flooring may reside in. Having a dense material like the recycled materials found in the QuietWalk family of products, blanket the underside of the flooring offering noise control…making the floor feel more solid underfoot, and helping floating floors act and perform like fastened wood floors. It will also properly support the joints of the floor, and will not crush over time due to normal traffic the floor will endure. There are ways to understand how underlayment materials will endure under pressure, check out the link in the notes below to our compression resistance video.
Additionally, a second story and multifamily living environments may need a lab qualified underlayment under the floor like the QuietWalk products to help promote harmonious living spaces. All QuietWalk products are HOA recommended with independent lab testing available for sound control.
There are many proclaimed “universal” types of underlayments on the market…it is always important to address how the underlayment will FIRST address and protect the subfloor concerns before moving on to the other attributes of the floor and installation. Starting from the bottom side up, first, is a good start to picking out the right underlayment for your new floor!
MP Global has a product selector tool, which is handy….it can be used to really drill into what product you need based on the application and product features that are important.
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You are about to install your new flooring. As you lay the first plank you realize that