Builders
Question: Javier R. / Project Manager for
Builder (Denton, TX)
We’re building three, 3-floor, apartment buildings – 86 total units.
They are closed up and drywall will be going in. Some of the floors just
got upgraded from carpet and pad to engineered wood in the living and
dining areas. The kitchens and baths will be tile. Bedrooms will still
be carpet. I attached a sketch of the floor construction and framing.
Same for all three buildings. We’ve gotten into trouble with wood and
tile before because of noise from above – people walking in shoes and
chairs being moved around. I’ve done internet research and there’s
dozens of products that claim to prevent this type of noise problem. But
there are so many different types, thicknesses, materials and prices.
What is acceptable for apartment buildings without over doing it? These
apartments are mid cost range for the area.
Sound-Answers.com
Please begin by visiting Sound-Answers.com’s
resource center and reading about Impact Isolation Class (IIC). We
recommend an IIC of around 55 for mid-priced apartment buildings (IIC 50
at a minimum). To achieve this (given the base construction you
provided) you will need to implement a special floor underlayment
beneath the finish floors in the units above and resiliently mount the
gypsum board ceilings in the units below.
The floor underlayment needs to be in the 5 mm to 10 mm thickness range,
preferably closer to 10 mm to achieve the recommended IIC 55. Acceptable
products include Kinetics Soundmatt (www.kineticsnoise.com)
(7.9 mm thick), Maxxon Enkasonic (www.maxxon.com)
(10.2 mm thick) and Ecore QTscu (www.qtsoundcontrol.com)
(10 mm thick). You will find installation instructions available for
each product on the manufacturers’ web sites. If you need to save on
costs, we feel that you do not necessarily need the underlayment under
the tile in the Kitchens and Bathrooms. These rooms are small, and a
person would not be able to ‘walk’ at full gate in these rooms. Of
course, you do not need the underlayment on the ground floors (no units
below).
In addition, mount the planned gypsum board ceilings to the underside of
the wood joists using resilient clips/hangers such as Kinetics Isomax or
model CRCH (or model WHDSM) compact neoprene ceiling hangers by Mason
Industries (www.mason-industries.com).
They are preferred over the old style resilient channels. These two
noise control measures combined with the planned base construction
(including the planned insulation between the joists) will achieve the
desired results ~ namely infrequent complaints. Of course, you do not
need the resilient clips/hangers on the top floors (no units above).
Beyond the question ~ In addition to using the floor
underlayment, you must also use an isolation strip around the perimeter
of the unit/room. The wood or tile floor must float on top of the
underlayment and not touch anything laterally except the isolation
strip. In the unit below, avoid or minimize penetrations in the ceiling
for lights and other elements. If unavoidable, build gypsum boxes up and
over the penetrating elements (take care not to negate any necessary
cooling/ventilation required by the element).
