Why Do I Hear My Kids Arguing?


The International Residential Code 2015, New Jersey Edition does not address any sound transmission requirements as the IBC does. So if you live in a townhouse or an apartment you may get a better night’s sleep than in your single family home. There are no requirements for air borne sound to be reduced between rooms such as bathrooms, bedrooms or for sleeping areas above or adjacent to a garage. Maybe it’s a good idea to address these if you are building a new home, doing some alteration work or creating an addition. The late Surgeon General Dr. William H. Stewart once said “calling noise a nuisance is like calling smog an inconvenience; noise must be considered a hazard to the health of people everywhere.” This is the same man who initiated health warnings on cigarette boxes!

Noise is around us every day and impacts our health in a multitude of ways. Some known effects are; hearing impairment, hypertension, ischemic heart disease, annoyance and sleep disturbance. For children, noise can impact language and learning development.

How can you keep your house a little quieter for studying or sleeping? There are ways to dampen sound with softer materials such as carpeting and drapes but between rooms you would really want to address the construction of your partitions. Your typical partition in a home is a 2×4 stud wall with a single ply of ½” gypsum wallboard on each side. This partition will give you an STC (sound transmission class) of approximately 34. STC of 34, what does that mean? The following is a guide of STC Values and how they correspond to what you can hear from loud talking in an adjacent room:

STC                 Audibility from a loud speech in an adjacent room

25                   Easily understood

30                   Fairly audible

35                   Audible but not intelligible

45                   Must strain to hear

48                   Barely audible

50                   Inaudible (loud music can be faintly heard)

So that STC of 34 is not bad but it’s not going help you if your teenager decides to play music while you are trying to go to sleep! So what can you do? There are many assemblies to give you a quieter wall. Adding a 3 ½” batt of fiberglass insulation in the wall will help but only give you a value of 36 so, in reality something else must be done if you believe this is a concern for your home. Adding a resilient clip to one side under the wallboard can increase the value to 50 which also happens to be the minimum requirement between attached dwelling units. Other methods are to add layers of gypsum wallboard or create a staggered stud wall.

Another point of noise entry is going to be doors and windows. Your typical interior hollow core door units have an STC rating of approximately 24 – 27 and a solid core door can get you up to and STC value of 35. Of course, you would have to have a seal at the bottom edge to get a true separation which would be very unusual in a house. In general, the windows that AGA specifies fall between 30 and 35 depending on the configuration and type.

Floor assemblies can also be addressed if you have a room below your bedroom that you are hoping to isolate. Your architect can add features into their design to accommodate a quieter separation. Be sure to let your architect know if you have noisy kids, if someone likes to stay up later than you watching television or you have a musician in your home.