There is no question that the Insulayment and Quiet Walk underlayment pad will perform as designed by the manufacture.
The use of sound barriers is quite common in neighboring associations used as either a thermal or sound isolator accessory. Traditionally 1/8” corks have been use under hardwood as sound isolators. These days, new generations of dense hypoallergenic fiber pads are also used to reduce noise transmission, out performing many corks.
Interestingly, the same fibrous properties of the pad meant to isolate against sound can allow for a certain amount of board flex or movement. Anytime ridged Hardwood is installed over a softer flexible surface, squeaks can result. It would be unreasonable not to expect some squeaks due to the use of any pad as an underlayment for ridged hardwood.
Insulayment and Quiet Walk is designed as an isolation barrier to dampen impact noise going from an upper living area to a lower living area. Glued-down or nailed-down wood floors are approved floor covering materials for Insulayment.
Do not use Quiet Walk for gluing down hardwood. Quiet Walk underlayment is designed with it's own plastic moisture barrier and is recommended for floating floors.
In order for any isolation barrier to function correctly, a certain amount of compressibility is required. A completely solid underlayment layer, one that allows no compression, is not an isolation barrier. The unique combination of fiber materials in Insulayment, along with the patented manufacturing process results in an isolation barrier with the density and compression resistance needed to achieve the benefits mentioned above, while offering optimal support of the floor covering materials. Although Insulayment has a density and compression resistance higher than most isolation barriers, a certain amount of deflection is to be expected when installed in glued-down or nailed down wood floors. Therefore, customers would want to weigh its thermal benefits against any possible squeaks.
This information is clearly referenced at the INSULAYMENT WEB site product description page. (A copy of this statement is below) and applies to both Quiet Walk and Insulayment
Deflection may cause a minimal amount of friction “floor noise”, especially in nailed-down wood applications. The normal noise factor will vary, from one installation to the next, depending on sub-floor type, sub-floor deflection, species and type of flooring material, fasteners used, relative humidity and the amount of topside pressure applied to the flooring material. For these reasons, “Floor Noise” is not considered a defect.
