Party House, Grow House, Room with a View

Exploring the History of a Home and a Neighborhood


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Reclaiming Gym Floors: eco-friendly beauty and soundproofing all in one inexpensive package

After weeks of stalking Craigslist, I was beginning to despair of ever finding affordable–let alone ecologically sustainable–flooring for Rocky Butte’s 3,000 square feet of public space (we will probably be re-carpeting the bedrooms). But yesterday I found 2,000 square feet of premium grade maple tongue and groove for $1 per square foot. It has been lightly used as the floor of the gym at a Christian high school in rural Oregon. With luck, we’ll be able to buy another 1,000 square feet from the same contractors.┬áHere’s a picture:

GymFlooring

Unlike gym floors bought through an FSC certified dealer, this flooring won’t come with an official FSC re-use chain of custody certification. But since we are buying it from the people who demo’d the floor, we know its story. And since–unlike more expensive certified repurposed flooring–we’ll have to take apart the dang floor ourselves, there is no question it really was a gym floor to begin with. Moreover, since absolutely nothing about owning a 5,000 square foot home made mostly of windows is eco-friendly, we aren’t exactly trying for any official certifications.

Traditional gym floors are made from maple tongue and groove stapled onto two layers of plywood or pine subflooring; this assembly is then floated on top of evenly spaced pads that allow the floor to absorb shock and, hopefully, save the knees and ankles of the athletes and dancers who use it. When the contractors demo’d the floor they cut the floor assembly into the large rectangular pieces pictured above. They are *heavy*! It took five of us many hours to load them onto a trailer and unload them into the garage at Rocky Butte.

Last week we almost had a chance to purchase 1,700 square feet of old growth Douglas Fir tongue and groove from an 1880s farmhouse, also at $1 a square foot, but the woman decided in the end to keep the flooring. It would have been an amazing opportunity–this type of flooring usually sells for $15 a square foot. Yet those beautiful old growth boards really belong in a smaller home that would respect and showcase the labor and history that they represent.

Our repurposed gym floors are much more in keeping with Rocky Butte’s history as a party house. We will have to pry apart the tongue and groove from its two layers of plywood backing and cut off/sand down the blind nailed staples. But we should be able to reuse most of the plywood when we create our own floating floors in areas of the house where soundproofing is desirable. As this article notes, floating your hardwood floor on two layers of plywood over either acoustic rubber matting or rubber gym pads is the most effective way to muffle impact noise. And the additional layers of plywood mass also help address airborne noise. Portland building codes will require us to muffle both impact (IIC) and airborne (STC) noise to at least 45 between the main floor and the accessory dwelling unit we hope to build in the basement. Since at STC 45 loud voices can still be heard as a low murmur, we hope to meet the higher STC 50 standard mandated in California. Repurposed gym flooring is the first part of putting that standard within our financial reach. Insulation, careful sealing of ducts and other passageways, and perhaps a floating/furred ceiling, will comprise the second half of the project.

Aesthetically, both first and third grade floors have their beauty, the former for its clear, smooth grain; the latter for its interesting knots and discolorations. Because first grade maple has become increasingly expensive, newer gym floors are increasingly made with third grade maple, also known as “seconds.” While both would be beautiful at Rocky Butte, the large open expanses of the great rooms will be accentuated by the smooth lines of the first grade maple. And while those who install gym floors sometimes retain the original gym markings to create visual interest, we are going for a more traditional look.

Don’t expect photos of the refinished floors for a long while yet . . .