I love soundproofing because it provides an incredible, immediate result for so many important aspects of life. It makes offices more efficient, is the reason why music, podcast, and radio production is able to create our most vibrant entertainment, and allows us peace in our homes. I work with so many clients to achieve their specific needs, but I also really love commercial soundproofing for residences because it takes the importance of these results and makes them possible at a society-wide level.
In the United States, multi-family residential buildings like apartments, condominiums, and townhomes account for 31.4% of housing, or 43.9 million residences. This is a vast chunk of the population. Soundproofing is so important in multi-family buildings that it is enshrined in building codes – a great example of government regulation, I must say!
As I will unfold in this article, floor soundproofing in particular creates a profoundly positive residential atmosphere that provides benefits that cascade down and throughout our society.
Florida, one of the hottest states in the United States for residence, has a red hot building industry and therefore building codes are critical to making sure new structures are built not only safely, but to maximize their benefits for the now and tomorrow.
4 Reasons Why Floor Soundproofing is Important
Floor soundproofing in residential construction offers a surprisingly powerful array of benefits:
1. Noise Reduction
We’ve all seen a scene in a popular sitcom where a neighbor’s loud footsteps from the floor above serves as a plot device. In addition to impact noise from footfalls, there are a host of other noises – moving furniture, dropped objects, shouting/talking – that are part of life for that unit but unwanted for everyone else. Multiply these sounds happening in dozens or even hundreds of units in multi-family structures and we’re talking an absolute cacophony.
By implementing effective soundproofing, specifically floor soundproofing, these noises can be contained within their individual units so that they do not negatively impact units above and below. A home is supposed to be peaceful, and floor soundproofing is the best way to provide a foundation for this peace to be possible.
2. Privacy
In addition to noises, privacy is of big concern in large residential structures. Just because buildings are multi-family doesn’t mean that each family or occupant in that structure has to interact with each other, and certainly not be privy to the goings on of neighbors and strangers. While noises are certainly annoying and limit peace and quiet, privacy is a more psychologically complex issue and therefore more important.
It’s not just a desire for important information to be kept away from ears that shouldn’t hear them, it’s just the concept of privacy in general. Soundproofing therefore is incredibly important in this regard to make sure that each home unit within a multi-family structure is allowed privacy.
3. Comfort and Well-Being
Noise and privacy are not just important issues for “superficial” reasons like not wanting to be annoyed or overheard, but they can impact us deeply to the point that our state of mind can be negatively impacted long-term.
Stress is one of the most harmful things for our body long-term and unfortunately one of the hardest to solve. The best way to reduce stress levels is to identify what is causing stress and to eliminate what you can, which can be a challenge. You can’t just quit your job and not have income, for example, because it is stressful, at least not easily or quickly. You can, however, identify smaller things in life that add to overall stress, like unwanted noise in your dwelling place or the fear that someone is listening to you. This is why soundproofing is not just to create a pleasant acoustic atmosphere in multi-family structures, but a literal tool to improve overall well-being.
If the 43.9 million households that reside in multi-family structures could be given a boost to their mental health and well-being from a relatively simple construction method, the positive effects that breeds for society are hard to quantify.
4. Resale Value and Marketability
In an economic sense, the above benefits mean that a multi-family building with solid floor soundproofing is going to be far more attractive than one without. When building large, multi-family structures, financial considerations are of top importance if not the entire reason for building, and therefore any addition you can make that will boost the structure’s value now and into the future, as well as being attractive for tenants, is a major benefit.
Understanding the Two Floor Soundproofing Rating Systems Used by Building Codes
While the benefits of soundproofing are profound when fully analyzed, they are important enough in simple terms that a minimum standard is enshrined in building codes. All building codes, including Florida’s, use the following two soundproofing rating systems for builders to use to make sure they are in compliance.
Sound Transmission Class (STC)
In acoustics, soundproofing is quantified by a rating system called Sound Transmission Class (STC). As its name suggests, the rating determines how much sound energy is transmitted as it passes through a material. For example, if loud music is played in an apartment unit at a certain decibel level, how much less will that level be after it passes through the ceiling to the unit above. Here is a handy chart showing STC ratings for common sounds.
STC RATING CHART | |
STC | What can be heard at this level |
25 | Soft speech can heard and understood |
30 | Normal speech can heard and understood |
35 | Loud speech can heard and understood |
40 | Loud speech can heard, but not understood |
45 | The threshold at which privacy begins |
50 | Loud sound can be heard, but are very faint |
60+ |
At this level, good sound proofing begins. Neighbors generally are not disturbed by very loud speech from inside |
The STC rating is specific for airborne sound, but this isn’t the only type of sound that needs to be accounted for.
Impact Insulation Class (IIC)
The second rating system for quantifying soundproofing in Florida building codes is Impact Insulation Class (IIC). This rating system focuses on structure-borne sound, such as the sounds from impacts like footfalls as well as vibrational sound from furniture dragging across floors or the rumble of a washing machine. IIC is calculated in the same way as STC by recording the energy of the initial sound and how much energy it has after it has passed through the assembly in question.
How the Florida Building Code Addresses Floor Soundproofing
Building codes can be complex, and for good reason. While it is critical to understand them in full, our focus here is an understanding of floor soundproofing and the requirements as defined by Florida Building Codes. To that end, here are the relevant sections pertaining to floor soundproofing:
Florida Building Code Airborne Soundproofing Requirements
In Section 1207.2 of the Florida Building Code, it states: “Walls, partitions and floor/ceiling assemblies separating dwelling units and sleeping units from each other or from public or service areas shall have a sound transmission class of not less than 50, or not less than 45 if field tested, for air-borne noise when tested in accordance with ASTM E90. Penetrations or openings in construction assemblies for piping; electrical devices; recessed cabinets; bathtubs; soffits; or heating, ventilating or exhaust ducts shall be sealed, lined, insulated or otherwise treated to maintain the required ratings.
This requirement shall not apply to entrance doors; however, such doors shall be tight fitting to the frame and sill.”
Florida Building Code Structure-Borne Soundproofing Requirements
In Section 1207.3 of the Florida Building Code, it states: “Floor/ceiling assemblies between dwelling units and sleeping units or between a dwelling unit or sleeping unit and a public or service area within the structure shall have an impact insulation class rating of not less than 50, or not less than 45 if field tested, when tested in accordance with ASTM E492.
How to Comply with Florida Building Code Floor Soundproofing Requirements
Now that we know the ratings we need to meet, we must look to the materials and construction methods necessary to do so.
Underlayment
Underlayment is the material placed between the flooring material and the subfloor. Typical underlayment is utilized for cushioning, support, and to cancel out any subfloor imperfections. When it comes to floor soundproofing, the right underlayment is the #1 way to meet Florida Building Code requirements, if utilizing material designed for this purpose.
The best underlayment to achieve this is Iso-Step® Soundproofing Underlayment, a powerful soundproofing underlayment that achieves STC/IIC ratings of 50+ even in non-concrete floor assemblies. When paired with Iso-Step® Soundproofing Underlayment Adhesive, this underlayment will be all that you need to meet Florida Building Code requirements. For a detailed look at how it works in the most common floor assemblies, see our charts at the bottom of this page.
The benefit of selecting a powerful underlayment option like Iso-Step® Soundproofing Underlayment means as a builder you have more freedom in selecting the actual flooring material. Tile, hardwood, and laminate, being hard surfaces, tend to transmit more noise, meaning lesser underlayment options may not be enough to meet Florida Building Code. Carpets have been traditionally popular not only because they are soft, but because they are better at transmitting less sound. With the right underlayment, the flooring option becomes merely an aesthetic choice, allowing more freedom.
Flanking Paths
As noted in Section 1207.2, the floor itself is the main objective, but there remains outlying areas that also need to be properly soundproofed, as sound is very sneaky and can transmit much of its energy through the smallest of cracks and poor seals. To deal with penetrations and openings in floor assemblies around the edges, Iso-Step® Perimeter Isolation Strip is the ideal pairing with Iso-Step® Soundproofing Underlayment to complete soundproofing of the assembly.
Ceiling Assembly
When considering floor soundproofing, it’s important to understand that this also means ceiling soundproofing, as most structures are multi-story and therefore the floor and ceiling is a single assembly for all but the bottom and top floors. While utilizing the correct underlayment material may be all that is required to meet Florida Building Code, it’s worth noting materials that can be utilized on the ceiling to provide further soundproofing capabilities.
My go-to soundproofing assembly for my customers looking for studio-grade wall and ceiling soundproofing is a combination of AudioSeal® Mass Loaded Vinyl (MLV) Soundproofing Barrier, Resilient Sound Isolation Clip (RSIC-1), and Green Glue Noiseproofing Compound. MLV is a similar concept to underlayment, as it is a material positioned between the studs or concrete and drywall to dramatically lessen the ability of sound to transmit through.
When used with Green Glue Compound and resilient sound isolation clips to decouple, truly impressive soundproofing is achieved, and certainly enough to go above and beyond that which is required by Florida Building Codes. As mentioned, this same trio of products offers builders the solution for wall soundproofing, too.
Work with Acoustical Solutions for the Best Floor Soundproofing Products to Meet Florida Building Codes
Soundproofing isn’t just music studios and movie theaters. It plays an incredibly important role in the composition of multi-family structures that lends to a better environment for tenants, increased property value for owners, and, of course, is necessary to meet building codes.
At Acoustical Solutions, we pride ourselves on offering the best soundproofing products to achieve this, as well as industry-leading expertise no matter the complexity of your build.
Give me a call today and I’ll be happy to take a look at your project and outline exactly the products and techniques needed to meet Florida Building Code and craft an acoustic environment that will achieve your regulatory and financial needs.
To learn more about how Acoustical Solutions can solve your noise control problems, use our contact form, call one of our Acoustical Sales Consultants at (800) 782-5742, or visit us on the web at acousticalsolutions.com.