In attached dwellings, sound transfers between adjacent structures. Hotel guests have experienced the lack of adequate sound privacy between room walls, and apartment building residents may have been subject to the sound of their upstairs neighbors' footsteps. Indeed, sound privacy is an attribute that helps makes detached ADUs preferable to attached units.
In contrast, detached ADUs can be quiet urban retreats due to not sharing structural walls with another unit. My ADU has thick, insulated walls, which deaden the sound of the busy city that surrounds it. But, inside the exterior walls, sound travels freely.
A collage of images of the finished artistic sound barrier |
Good small house design attempts to make a place feel large despite the smaller size. This is accomplished by designing a relatively open floor plan. This means conjoining the living room, dining room and kitchen, into a "great room". Vertically, ceilings are lofted, and ideally, parts of the 2nd floor ceiling should also be visible directly from the ground level to create an illusion of grandeur.
Clean indoor air quality design utilizes hard surfaces instead of rugs and carpets, which tend to trap atmospheric deposition and dust mites (and their excrement), collecting and exporting particulate matter into the ambient indoor air that we later breathe.
Deliberately utilizing both of these design techniques, our ADU had both an open floor plan and hard surfaces (concrete and hardwood floors). Unfortunately, when coupled, the byproduct of these two design techniques was noise reverberation from one room to the others. Sound tended to reverberate off of the hard surfaces and it traveled easily from one open room of the house to another.
Prior to building, I wasn't sure how the sound would behave in the ADU, but while living in the ADU over the last ten months, I have experienced it first hand. Noise transfer has actually caused me to loose sleep this year- no laughing matter for a lover of sleep.
For example, if my partner woke up and quietly made coffee while I was sleeping, it was audible enough that it woke me up. If I watched a movie downstairs at night, it was very easy for my partner to hear it from the bedroom. When my dog was lying in the living room scratching behind her ears, it jingled her metal name tag and it was like she was shaking a tambourine.
In the design phase, we'd considered the possible audio impacts of the vertically open floor plan, but thought that it would be wise to actually live in the ADU before making a decision about whether, and how, to enclose the bedroom walls to prevent the transfer of sound from the downstairs to the bedroom.
Arriving at the Sound Barrier Design Solution
My partner and I loved the look of the opening to the bedroom, but it wasn't worth continuing to lose sleep over it. Our design goal was to develop an artistic sound barrier that would still let light pass through the house, but that would cut down the amount of reverberating noise into the 2nd floor bedroom. I worked with a Portland craftsman and friend, Eric Bohne, to develop, design, and execute a functional design to visually fit alongside the stunning metal handrail and the alternating tread staircase to the attic.
After many iterations of design ideas (which I won't bother to describe, but you're welcome to see in the photo and video collection below), we settled upon a design that would accomplish the desired goals. We decided to use stained glass as the medium, structurally connect the pieces with a steel frame. This captioned photo and video collection shows the chronological steps of the design, building, and installation process. There are ~65 pictures and ~5 videos in this collection.