I’d like to expand on my last post (Out, Damned Spot!) by breaking down some barriers…or, rather, by talking about why you can’t simply rely on walls to provide speech privacy and noise control in private offices.
If you have an office, your level of acoustic satisfaction is likely higher than that of your coworkers in cubicles (and definitely better than those in open desk or benching environments), but in many cases, noise and lack of privacy to adjoining rooms still interfere with your ability to do your job. You either have to put up with the conversations and activities taking place outside your door…or shut it and risk being seen as anti-social.
Maybe that’s why most of you leave your door open the majority of the time, exposing your office’s biggest Achilles’ heel. While your walls alone may range from 40 to 55 STC (significant blocking of sound), your office’s cumulative STC rating drops to around 7 (practically no blocking of sound) when you open the door. In this case, you may have less noise control than your open plan compatriots!
But even when the door’s closed, sounds originating in your office can find their way into neighboring offices (and ears) using a variety of pathways: walls, plenum, duct-work, and return air grills, as well as any gaps along the window mullions, ceiling and floors, and more. If the background sound level in the adjoining spaces is lower than the speech entering them, these weaknesses can dramatically impact your privacy. With today’s building standards, that’s often the case.
If you’re sitting in a deck-to-deck fortress, don’t feel too smug. While this type of wall construction increases acoustic isolation, it also substantially raises costs and reduces flexibility. And, just like any other type of wall, even minor penetrations can significantly reduce its acoustic performance.
If sound masking coverage is included for the closed rooms in your facility, the background level in these spaces will increase to between 40 and 45 dBA, protecting you against sound leaks and providing you with greater acoustic control...even when your door is open.