Everybody Hertz: How to Deal with Annoying Low-Frequency Noise

30 Sep Everybody Hertz: How to Deal with Annoying Low-Frequency Noise

Often constant and usually monotonous, a low-frequency noise or hum in your home can make you feel like you are under siege. For some, a low-frequency noise disturbance can be severe enough to warrant the use of earplugs.

What’s more, you might feel alone in experiencing a nuisance noise. Because hearing is subjective, you can be nagged by a persistent low-end hum while others around you find it tolerable—if they notice it at all.

Adding to the trouble is the way disturbing noises seem to get louder in the evening. This is because road traffic and other exterior noise sources taper off at night. During the day, these sounds can help mask a nuisance noise, so when they disappear, the low-end hum takes centre stage.

Where Does Low-Frequency Noise Come From?

Most low-frequency noise is attributable to mechanical or electrical units either inside or outside a dwelling.

Many new developments are vertical villages, where numerous apartments co-exist alongside parkades, supermarkets, swimming pools, gyms, and function rooms. We reside in smart buildings with many moving parts—motors, pumps, fans, boilers, transformers, servers, and generators, all working to ensure our comfort.

Finding the Source of Nuisance Noise

Identifying the presence and source of low-frequency noise requires careful investigation. At BKL, we work with you to quantify, locate, and isolate the nuisance. We generally start by asking the following questions:

• How would you best describe the noise? Its amplitude, tone, length, and intermittency?
• When and where do you specifically experience the noise?
• How long has the noise been present?
• Can the strata, landlord, tenant’s association, or neighbours corroborate your complaints?

Regulating Low-Frequency Noise Disturbances

Many municipalities in the Lower Mainland have statutory bylaws that specify acceptable overall noise levels in living rooms and bedrooms. Unfortunately, these criteria are inherently biased against low-frequency noise because they do not consider the tonal component.

Best Practice Guidelines for Nuisance Noise

Though we always account for local bylaws, property rules, and tenancy agreements, our assessments also consider interior noise criteria outlined in best practice guidance documents, for example, Chapter 51 of the ASHRAE Handbook, published annually by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE); and Guidelines on Community Noise, published by the World Health Organization (WHO).

The WHO’s Guidelines includes criteria for peak noise levels relating to sleep disturbance. The ASHRAE Handbook outlines acceptable noise criteria within bedrooms and living rooms, per octave band, thus providing acceptable limits on low-frequency sounds.

Investigating Low-Frequency Noise

Our investigations can take two paths: One for clients who have the support of their strata council, building manager, landlord, or neighbours. Another for those who don’t.

For investigations where the noise has been corroborated by all parties, we conduct an active investigation. We visit the property, install a sound level meter, and analyze the ambient noise for tones and specific acoustical features. Once we identify a nuisance noise, we review the building’s mechanical units and locate the noise source through a process of elimination. After we find the offending unit, we determine if the noise is attributed to a specific operation or component. From there, we make recommendations for mitigation.

For these investigations, we need access to the mechanical rooms and a suitably qualified person to power cycle specific equipment. The process is usually completed in a few hours.

For cases without corroboration, especially where relations have broken down, our investigations take on a more evidentiary process.

First, we install a sound level meter in the worst affected room, either a bedroom or living area, and measure continual noise levels for a period of 24 to 96 hours. Then we analyze the noise data in third octave centre band frequencies to identify specific tonal content. When our analysis is complete, we rate the significance of noise levels against applicable bylaws and best practice guidelines. Our findings in these investigations are often used as evidence to support complainants in situations of remediation, civil cases, or tribunals.

Solutions for Noise Disturbances

Living with nuisance noise can be debilitating—especially when no else seems to notice it. Moreover, constant noise disturbance can exacerbate on-going health concerns, particularly heart issues, hypertension, anxiety, and stress.

We encourage anyone experiencing nuisance noise to work with their strata council, building manager, landlord, or neighbours to resolve the issue amicably.

NOTE: Unfortunately, at this time we are experiencing an exceptionally high number of requests for acoustical services, which in combination with the logistical delays caused by the existing Covid restrictions imposed by the Health Ministry, means we are not able to accommodate private resident enquiries or Strata related enquiries at this time. We thank you for your understanding at this time and hoping to work with you in the future.

Written by Nick Dobbs