Six Reasons Why Acoustics, Noise, and Vibration Control Projects Fail
A.K.A., Top 6 “Soundproofing Fails”
#1: The solution design was flawed or misguided
One of the main causes of failure in acoustics, noise and vibration control projects is a flaw in the solution design. Acoustics issues can be complex and difficult to solve. A solution that worked in one building can have no impact whatsoever in an apparently similar property due to differences in the sound source and the existing conditions hidden behind finishing layers. (See this article for a good primer on acoustics designs.)
The constructor may copy a noise control design and expect to meet the results advertised by a product manufacturer, not realizing that the site conditions do not meet the lab conditions of the test and the design will not perform as expected.
In many cases, the design failed to address all the elements of construction needed to solve the problem. This can include “flanking paths” over walls, ventilation ducts, and wall penetrations for electrical and plumbing systems. In others, the dead weight of an appliance wasn’t calculated and resilient mounts placed underneath it were fully compressed and simply transmitted the vibration into the floor below anyway.
Design problems can also happen when manufacturers and distributors oversell the acoustic properties of a product (see more below). The constructor may copy a noise control design and expect to meet the results advertised by the product manufacturer, not realizing that the site conditions do not meet the lab conditions of the test and the design will not perform as expected.
In many cases, retrofitting an acoustic solution into an existing building requires an extraordinary level of design detail that the average constructor doesn’t have the time and expertise to manage effectively.
Seeking professional advice and taking due diligence through every stage of the project are key steps for a constructor to generate a successful result.
#2: The budget was unrealistically low
Every project has budget limitations and acoustics projects are especially costly. Materials are pricey, engineering consultations require well-compensated experts, labour requirements can be three-to-five times the typical costs of installing demising walls, and there are almost always unexpected surprises that add time and materials to a project.
Trying to cap the budget by substituting materials or short-changing a sub-contractor will lead to shortcuts. And shortcuts in acoustics are a primary cause of failure. Doing it twice is always more expensive than doing it right the first time. If the budget isn’t available, then installing a partial solution is, usually, a waste of money.
Be prepared for the cost of acoustics and budget accordingly to ensure the results meet your expectations.
#3: Products were sold as “magic bullet” solutions
Vendors and sub-contractors may oversell a product’s features to increase their contract with the owner or constructor. Installing extra insulation or a mass loaded layer on its own won’t make a wall or ceiling assembly dramatically better at dampening noise. A simple rubber pad won’t stop vibrations caused by heavy equipment from transmitting into a concrete floor slab.
Acoustics are a scientific discipline because it involves an incredible amount of complexity and mathematics. Noise and vibrations are composed of energy waves with tens of thousands of variations that react uniquely to different materials, room shapes, building structures, and other physical features of the environment.
A single product is unlikely to solve a complex problem on its own. With high costs and high risks, the old adage of “buyer beware” stands true in acoustics projects as it does with any other purchase.
Noise control designs are often like a layer cake and several different types and densities of materials are needed to achieve the desired result. Designs should reflect the root causes of the problem and be comprehensive for them to work effectively.
#4: A sub-contractor was hired to solve the problem
Specialized contractors can provide excellent and valuable services, but they are not acoustics experts. Some may claim to install “soundproofing”, but what they mean is that they are familiar with some noise control wall and ceiling assemblies. A typical demising wall solution provided by drywall contractors includes mineral wool insulation in between the studs, resilient channel, and two layers of fire-rated drywall. This can improve a sound transmission situation, but it was designed in the 1970s and may have no impact at all if the issue is low-frequency sound or mechanical vibration that is being transmitting through the structural elements of the building.
#5: The contractors/installers failed to follow the solution design
Acoustics and noise control designs require an extraordinary level of detail compared to other types of construction. Following 90% of the instructions can lead to a complete and total failure of the project.
Constructors need to keep a close watch over crews to ensure that the specifications of the acoustics design is fulfilled down to the last detail. If the installation is not 100% completed to specifications, then it’s likely to be a failed project. It can also be catastrophically expensive to fix.
Intensive quality control inspections are a must to avoid expensive re-installations, disappointment and lawsuits.
#6: The solution design was changed during construction
Altering the design and adding elements that weren’t considered during the analysis of the problem can lead to disappointing results. A wellness or “quiet room” in an office space can be rendered useless by adding in pot lights. A confidential meeting space can become everything-but-private due to the addition of HVAC system ducts without sound dampening that run throughout the office.
If the design is changed in any way, the acoustics should be revisited to ensure that the changes do not create an unintended failure that nobody notices until the finishing is completed.
Steps to reduce your project risk
There are many more reasons why acoustics projects fail, and one thing is for certain: these projects can be high risk due to the costs and complexity involved. If there’s any chance you may end up on the wrong side of the decibel metre after finishing the project, even a brief consultation with an acoustics designer can put you on the path to success.
It’s often well worth the investment to partner with an acoustics engineer or consulting firm to design a solution and manage the risks of failure and ensure a successful acoustics project result.
