SHHH…TRADE TALK ABOUT QUIET
Features and benefits of construction materials are core to the concrete business. One of the attributes of concrete is its superiority over stick structures when it comes to quiet.
Industry authorities are on the same page when it comes to the sound insulation value of concrete.
Concrete buildings.org reports: “Concrete walls built with insulating concrete forms effectively buffer a building’s interior from the outdoors. The thick ICF sandwich of a massive material (concrete) with a light one (foam) sharply cuts fluctuations in temperature, air infiltration, and noise. They keep buildings' interiors more comfortable and quiet than ordinary wood frame walls.”
The benefits of acoustic management using concrete aren’t just a discussion in the USA. Coming from Canada, Resisto.ca reports: “Concrete is an excellent acoustic insulator from airborne noises. However, since concrete is a very hard material, it reduces the acoustic performance in terms of impact noises, which it conducts.
“When designing a building, the selection of a structure with or without concrete should be considered. In the case of a building with five or more floors, there is no choice because the National Building Code requires a structural concrete slab. It is recommended that you use soundproofing products specifically designed to increase acoustic performance by reducing impact noises.”
Concretethinker.com reports that concrete walls buffer outdoor noise and the indoor environment, highway noise, and indoor noise between adjoining spaces. “The greater mass of concrete walls can reduce sound penetrating through a wall by over 80% compared with wood or steel frame construction. Although some sound will penetrate windows, a concrete building can be two-thirds quieter than a wood or steel frame building. Concrete panels also provide effective sound barriers separating buildings from highways and industrial areas from residential areas.
“Compared to a typical wood frame wall, only about one-quarter to one-eighth as much sound penetrates a concrete wall. A 2x4 wood stud partition wall with ½ inch gypsum wallboard on each side has a Sound Transmission Class (STC) of about 35. With furring, insulation and wallboard the STC values increase to 63 for 6 and 8-inch thick concrete walls. Bare concrete and masonry walls have STCs ranging from 45 to 50. Standard flat panel ICF walls have STCs in the range of 55-60.”
The hush concrete can provide made headline news in the New York Times in 2006 when Velocity condominium complex developers of Hoboken used 7-Inch concrete slabs to encase the 128 dwelling units. The decision to go the extra concrete mile was in response to buyers’ Number One requirement: To NOT hear their neighbors.
Velocity developers used precast concrete pieces for the building’s superstructure, a method usually used only in monumental government structures or for heavy industry.
A quiet building isn’t only a coveted standard for New Yorkers. In the Southern Hemisphere, Homestead Concrete Homes in New Zealand uses high-density concrete walls to manage nearby noisy main highways, railways and airports in urban centers. Homestead reps report that a concrete home is two-thirds quieter than a conventional home.
Concrete applications, of course, deliver different levels of soundproofing benefits. Staff writers at www.ConcreteConstruction.net vetted recommendations by readers on ways to improve the benefits of concrete in construction, reporting: “Tests have shown that porous surfaces with interconnected pores (like ceiling tiles) from the surface to the interior work well for sound absorption. At the porous surface, the energy of sound is converted into heat. However, the same factors which make good sound absorption provide poor sound insulation.
“Porous concrete absorbs sound but has poor sound insulation, or a low STC (sound transmission loss). Therefore, painting or plastering porous concrete reduces sound absorption and increases its sound insulating characteristics. The sound absorption coefficient for plain cast concrete is about 0.02, indicating that about 98% of the sound energy is reflected by the surface. The more the concrete weighs, or the denser the concrete, the more sound insulation (the greater sound transmission loss) rating.”
When homebuyers are promised quiet and don’t get it, they are more inclined today to take legal action. In a forum on https://streeteasy.com, a reader asked for advice: “I bought a new conversion condo and the building is still being constructed and converted. The building was marketed as having very sturdy, soundproof condos due to the 12” thick concrete floors. But, it has been anything but quiet. The developers cheaped out by laying the hardwood floors directly on the concrete or laying a think cork material underneath the hardwood floors… people in this building spent around $1 million only to have noisy ceilings…is unacceptable.”
One reader who goes by the name of SlipperyPete responded: “Sue the bastards. Multiply the dollar value of your annoyance by one thousand, multiply that by 365 days, multiply that by 50 years, and now you have the amount of damages you should seek.”
Concrete has proven benefits over frame or and steel construction. The proven authority for concrete cutting equipment is Acecutting.com with all the masonry tools and equipment needed to do the concrete job right the first time.