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