The construction of our “Flats on Savin” project is really starting to take shape. The Hush-Frame rafts have all been installed with a layer of 7/8” wood strapping. Insulation will soon be in place and the final layer of the system, drywall, will follow.
One of the most important aspects of the installation has been the ‘buy-in’ of the G.C.’s sub-contractors. All of the rough electrical, fire alarm, HVAC must be isolated from the studs. This isolation prevents any transition of sound vibration to the strapping and the drywall. Bald Hill Builders and their subs have been working hard to ensure that all the roughs are fastened to the strapping. In addition, when the drywall is installed, the contractor will use drywall screws no larger than 1 1/4” to ensure there is no fastening through the strapping and into the studs. This kind of attention to detail will pay dividends to the proper execution of the system.
Below is a collection of data that was gathered on-site after the windows and sheathing were installed and prior to drywall, insulation, and siding.
On Wednesday April 19, 2017 @ 10:00am the following reading were collected from Bedroom #1 in Unit 206 on the Second floor.
Ambient sound facing away from I-93 – 46 dB (Delta - 8 dB)
I-93 Ambient base sound - 56 dB (Delta - 9 dB)
I-93 Spike from truck - 63 dB (Delta - 15 dB)
Ashmont Train arrival to Savin Hill - 70 dB (Delta - 12 dB)
Ashmont Train departure from Savin Hill - 64 dB (Delta - 22 dB)
Braintree Train passing at full speed - 73 dB (Delta - 22 dB)