Condo dwellers look for ways to turn down the volume

When Diamond Schmitt Architects began designing a luxury High Park condo for Daniels Corp. four years ago, the firm knew it faced an unusual technical challenge: the sound and rumble of the Bloor subway that passed just metres from the parking garage. Drawing on a Belgian solution used for the Four Seasons Centre for the Performing Arts, DSAI installed a series of giant steel-encased rubber buffers alongside a basement concrete wall to isolate and reduce vibrations.

Most apartments and smaller residential projects don't end up perched atop a subway. But in most multiunit developments, noise – from tenants, mechanical systems or the outside world – is a frequently aggravating fact of city life.

Thanks to paper-thin walls, you can hear your neighbours bang, fight or have sex. An intermittent rattle with no obvious source interrupts sleep. And the windows don't seem to block out the sound of traffic from the street below. Acoustics experts say that buyers and renters should understand that in most apartments, it's impossible to completely banish external sound.

"People in condos expect not to hear those things and that's not realistic," cautions acoustics expert Brian Chapnik, co-founder and principal of HGC Engineering, in Mississauga. But, he adds, "If you can hear what your neighbour is saying, there's a chance there's a deficiency and it should be tested."

Investors, home buyers and condo corporations can avail themselves of various technical solutions that mitigate certain types of noise, although not all builders will ensure that these features are standard in their projects.

As of January, 2017, they also have more regulatory remedies and tougher building code guidelines regulating the acoustical performance of new buildings. Under earlier rules, construction materials had to satisfy acoustical lab tests. But the regulations that came into effect last year require builders to actually test the performance of walls, insulation and other components as built.

If these don't satisfy the new national building code requirements, buyers can now make a claim under Tarion, the provincial homebuilder warranty program (Building Bulletin 19R lays out the standards). "If you are a builder," engineering consultant Aercoustics warned in a bulletin about the changes, "you know that when bad acoustics occur, condo owners will complain. If you don't give acoustics its due care, you will run into problems."

The rules apply to any project where construction began after Jan. 1, 2017, Aercoustics principal Payam Ashtiani says, adding that investors should ask developers if their design teams include an acoustics consultant.

There are various sources of noise: impact sounds, mechanical noises and external or environmental sources. But for buyers, some of these can be difficult to gauge. Acoustics experts have some advice:

• With existing units, visit at different times of day, and especially in the evening, when the building’s occupants are likely to be around.
• Think about height. Ambient street noise resolves into a background hum in units further up. But pay attention to nearby high-rise buildings. If the apartment is at the same level as the mechanical rooms atop neigbouring high-rises, you may end up hearing those sounds.
• Make sure to compare the sound levels when windows or balcony doors are open and closed.

But, as Mr. Ashtiani notes, "There's no way to know what's behind a wall visually or whether it has been constructed properly. It's incumbent on the buyer to see if there are complaints about the acoustics of the building."

Buyers can also hire an acoustics consultant. Typical testing sessions run from about $2,500 to $5,000, depending on the extent of the analysis.

In high-rise projects, certain types of deficiencies show up regularly and can be fixed without too much difficulty within the unit. For example, sound from a central heating system may seep into an apartment because ducts haven't been properly sealed.

But other more systemic problems, such as travelling vibrations from chillers or other mechanical systems on the roof, will require abatements the condo corporation will need to finance.

In new-build single-family homes, sound from flushing toilets, for example, can be efficiently transmitted around the building thanks to the presence of wood studs, which are very effective at shifting vibration to dry wall.

Mr. Ashtiani says it's possible to isolate those vibrations by installing rubber gaskets and fasteners or "resilient clips" between the dry wall and the studs. He says these aren't automatically installed, so buyers or renovators may need to ask the project architect and contractor to use them. "The cost isn't extremely prohibitive."

In most high-rise projects, floors – which tend to be concrete slabs – are also significant sources of transmitted noise. Mr. Chapnik points out that the standard use of laminate hardwood on top of an acoustic underpad will only do so much to contain sound transmission through the floor. It's possible to install thicker subfloors – at least five centimetres thick – but these, or dropped ceilings with acoustic tiles, tend to only be standard in luxury boutique projects.

Ultimately, acoustics experts advise clients to be realistic about how much they can achieve with such remedies. As Mr. Ashtiani says: "Sound isolation is not sound proofing."