| There is more than one method for installing | | | | be problems with the drywall sitting level on the |
| mass loaded vinyl to obtain maximum effect. The | | | | studs. If your studs are 16" on center, then every |
| standard of the industry is to install the MLV | | | | other stud will have 1/8" of increased width |
| directly to the stud or joist framing using an | | | | compared to the studs that don't have the MLV |
| industrial stapler or heavy-duty roofing nails that | | | | weaved a top of them. To keep the drywall even |
| have the large plastic heads. This method is | | | | on both sides, a sound isolation tape can be |
| known as the membrane or septum method. The | | | | adhered to every other stud that that is not |
| MLV works well when placed on a wall or ceiling in | | | | covered with the weaved MLV this will make all |
| a membrane fashion, however it can also be | | | | of the stud surfaces flat and even and the |
| sandwiched between 2 layers of drywall or other | | | | drywall will rest evenly on the studs. |
| type of wallboard. The jury is still out on what | | | | From the feedback of our contractors in the field, |
| thicknesses of drywall is best. For better | | | | we have discovered that the more a wood |
| frequency diffusion, it is best to use a layer of 5 | | | | structure is dampened, the better the |
| 8" drywall then the MLV as a septum (a | | | | soundproofing will be in a wall or ceiling assembly. |
| sandwich) and then add a layer of ½" | | | | This is especially true for impact noise from |
| drywall or Homasote. The dissimilar materials do | | | | above. There are many ways to dampen a wood |
| help in the soundproofing effort especially when | | | | frame assembly and some are more effective |
| we are looking to get every STC point we can | | | | than others. Some contractors have used blown |
| get with as little effort as possible. | | | | in cellulose in order to dampen the joist or stud |
| There is not a lot of information on the Web in | | | | structures, but cellulose has no mass and though |
| regards to alternate methods of mass loaded | | | | it will help to a degree, it is much less effective |
| vinyl installation, hopefully we will be able to | | | | than using blown in closed cell foam, or my |
| explore this here. | | | | favorite (which requires some ceiling demo) is to |
| If you are constructing walls using the staggered | | | | line the cavity areas between studs and joists |
| stud method, it would be beneficial to actually | | | | with a closed cell vinyl nitrile foam mat (America |
| weave the vinyl in an out of the staggered stud | | | | Mat is a great choice) for maximum dampening. |
| assembly itself. The above picture gives you a | | | | The foam mat would be glued to the studs and |
| rough idea of how this would look. The key to | | | | the wallboard in the stud cavities (provided you |
| weaving MLV (or any barrier material) is to seal | | | | have drywall on one side of the wall only). This |
| the vinyl as best as possible. In the case of a | | | | insures that the wooden structure is completely |
| horizontal weave (most common weave) it is | | | | dampened and if sealed properly will offer extra |
| best to overlap the seams by at least 1" and seal | | | | soundproofing as a result of sealing those cavities. |
| that overlap with acoustical caulking as well as a | | | | Sealed dead air space is God's natural |
| quality seam tape. The weaving of MLV also aids | | | | soundproofing method, as I like to call it. I am |
| in the defusing of sound waves. This works much | | | | sure you have read many of the analogies |
| like the dissimilar materials except "turbo charges | | | | regarding sealed dead air. If you were able to seal |
| it". | | | | the dead air space and actually create a vacuum |
| You can also use the weave on a standard stud | | | | in that space, you'd be amazed at the amount of |
| wall provided there is no drywall installed on either | | | | sound transmission that would be blocked. |
| side of the studs. (just open studs) This weaving | | | | I hope this little narrative helps you especially if |
| method can be foiled by stud cross members, so | | | | you are doing new construction for a home |
| it is best to have only vertically installed studs if | | | | theater, or music sound studio in your home. |
| you are planning to do the weave. If you weave | | | | Thanks for reading and learning together. This is |
| the MLV on a normally studded wall, there may | | | | Dr. Bob…..Out!!!!!! |