Mass loaded vinyl is available online through many sources and nearly each source has their own name for this material. MLV, acoustic barrier, and probably 25 different brands. Ultimately, if it's a 1 LB vinyl, then it's a 1 LB vinyl. Very little difference from manufacturer to manufacturer and no noticeable difference in performance, appearance, or other product specs. In this article, we're going to simply refer to this material as MLV.
WHERE SHOULD MLV BE USED
MLV should be used in two types of applications: 1) Simple assemblies that have limited to no other sound control products and 2) Assemblies that have resonance issues.
Simple assemblies include assemblies that have: limited mass (single layer drywall on each side of the wall), no other sound control products (damping compounds, resilient clips), and areas where other products can't be installed (around duct work and pipes, over doors and windows, or sewn into curtains).
Installing the same material over and over again, like 3 layers of 5/8" drywall back to back, will improve low frequency isolation because of the all the mass. But the resonance issues of 5/8" drywall are made worse when multiple layers of the same material are included in the same assembly. This is true for any rigid building material, whether drywall or wood, in any thickness.
WHY MLV WORKS
MLV is an acoustically dead material, meaning that it does not resonate like common building materials. All rigid building materials have resonance issues. A single layer of drywall will provide a similar STC rating to 1 LB MLV, but that single layer of drywall will perform inconsistently (resonance issues) at various frequencies. Meaning it might test well for an STC rating, but not perform well in the real world. Combining MLV in a simple wall or ceiling assembly will provide significant gains. A wall with a layer of drywall on each side will have an STC rating of 35. Option 1, include 1 LB MLV on one side and the STC goes up to 44. Option 2, add just a second layer of drywall on one of those sides and the STC rating only bumps to 37. What this means for you is that the MLV can double the performance of a common wall while a second layer of drywall will only slightly improve the wall. Possibly not even enough for most people to notice.
In other simple assemblies, such as wrapping duct work, drain pipes, hanging over doors, windows, or curtains, there simply isn't another solution that works. The flexibility of MLV and ability to tape or adhere to virtually any surface gives MLV a distinct advantage over other products on the market. MLV can also be customized to included quilted fiberglass to improve decoupling, fabric to reinforce the MLV, and aluminum or foil/scrim faced options. All of these types of MLV are available on our site.