What to Do About Noise?
- What Noise Mitigation Strategies are being used?
- Optimized Profile Descent
- What is a residential Sound Insulation Program?
- Reducing Noise Inside a House
Many large airports in the United States have created residential sound insulation programs. The goal of these programs is to reduce noise impact on nearby communities. These programs provide sound insulation modifications to homes close to airports with a large amount of air traffic activity. Whether or not a homeowner is eligible for a sound insulation program depends on the airport's capabilities and resources.
Each airport designs its own, tailored sound insulation program to address local community issues. Each airport uses a different process to determine who is eligible for sound insulation and the timeline for the insulation process to occur.
At many large airports, a Part 150 Noise Compatibility Study is completed. The study identifies areas around the airport that are most prone to noise impact. These areas are identified by noise contours. Noise contours determine the annual average daily level of noise generated by aircraft in that area. These contours are mapped to find homes that may qualify for the sound insulation programs.
In most cases, to be eligible for a sound insulation program, a homeowner must live inside the 65 DNL (day-night average sound level) contour surrounding the airport. Most of the residences inside the contour must be single-family or duplex houses, but this can vary from airport to airport.
Sound insulation programs are mainly funded by the Federal Aviation Administration (FAA). An airport that wants to start a sound insulation program can request assistance from the FAA. The airport is evaluated to determine if they are in need of such a program. An example of this process follows.
Some airports also collect Passenger Facility Charges (PFCs) to help fund sound insulation programs. A PFC is a surcharge applied to the ticket of each airline passenger departing from that airport.
The FAA authorizes airport executives to use the revenue from PFCs for
- Noise compatibility measures
- Noise compatibility planning
- Airport planning and development projects
Sound insulation programs try to reduce aircraft-related noise levels inside homes by installing sound insulated doors and windows and/or performing air conditioning modifications. There are many different methods of insulating a house. Some examples include:
- Window modifications
- Vent modifications
- Wall and ceiling modifications
- Heating, ventilation, and air conditioning modifications
- Door treatments
It is important to understand aircraft noise will not be completely eliminated in a sound insulation house. Sound insulation is one of many techniques used to minimize aircraft noise in communities near airports.
Not all airports have sound insulation programs. These programs are dependant on many different issues. Community members should contact their local airport to see what types of programs they have, if any.
Some airports provide acquisition programs. This is the voluntary purchasing of a house in an area with a DNL greater than 6.5. For acquisition to occur, the property must also be zoned from residential to a compatible land use, such as commercial or light industry. The property owner is paid fair market value for their property at its highest and best use. The owner is also provided relocation assistance. Source, click here.
An example of a Sound Insulation Process:
When a group of homes is determined to be eligible for sound insulation, the homes closest to the airport are the most affected and are insulated first. Most airports then work outward from the airport and insulate homes on a block-by-block basis.
The homeowner will be notified if their home is selected for sound insulation. Homeowners are then invited to a general information meeting at the airport. They are given detailed information about the program their house qualifies for.
Almost all sound insulation programs are voluntary. When a house is selected, the owner decides whether or not to participate. To participate, various documents need to be completed. These documents give the airport permission to evaluate specific noise problems and concerns and begin the modifications process.
Before renovations can begin, tests and surveys must be done. These tests might include
- A noise test done by a consulting agency
- Architectural and mechanical measurements
- Product selection
These tests ensure that the right types of sound insulation modifications are made. Modifications can include
- Replacing windows with higher quality sound insulated windows
- Adding better insulated doors
- Insulating the ventilation system, walls, and attic of the house
Homeowners are notified in advance when these tests will take place. They should expect each test to take about one to five hours. Homeowners are usually required to be present for each of the tests.
After the changes are determined, the airport presents the proposed modifications to the homeowner. The homeowner must accept the design and sign a contractual agreement before work begins. The homeowner may make slight changes to the modifications presented. To ensure the effectiveness of the insulation, changes are usually limited. After acceptance, the agreement becomes a legal contract between the homeowner and the airport.
After the agreement, a homeowner cannot make changes to the modifications (i.e., finish items, colors, window/door styles etc.). The homeowner also agrees not to perform any other construction on the house while the sound insulation modifications are being made. The homeowner may not hire the sound insulation contractors to perform additional, unrelated work. Some homeowners also have to sign aviation easements or other related documents.
The airport solicits bids from local contractors and decides which contractor will be used. The contractor schedules a time to make final measurements of the home and prepare it for renovations. The contractor will then submit a schedule for completion of the project.
Renovating an average home takes a few weeks. Before contractors begin, the airport should offer the homeowner information to assist in construction preparation. Project supervisors will conduct several inspections during the construction process. This ensures that the work is being completed properly and conforms to the specifications.
After the modifications are completed, post sound insulation noise measurements might be conducted. The goal of a sound insulation program is to reduce interior residential noise levels to at least 50 dBA. A successful sound insulation program will reduce the noise in a home by 30 to 35 dBA.
Most sound insulation programs also issue a warranty package after the home has passed the final inspection. Most contractors guarantee warranties for one year. Many individual products carry a longer warranty guarantee by the manufacturer.
For additional information, click here.
For definitions of words used in this section go to the NoiseQuest Glossary of Terms.