The following is a list of FAQ's and responses provided to my office, by Minto, ahead of Avalon Vista phase 2 construction commencing. Please don't hesitate to reach out to Minto inc. should you have any questions not found here.
Vibrations and Frequently Asked Questions
Construction activities and heavy equipment associated with the Avalon Vista
Phase 2 Subdivision project will produce low intensity ground vibrations. This is
quite common and typical observed vibrations are unlikely to cause damage to
adjacent structures. The vibrations are more noticeable in this part of Orleans
because the clay soils in the area tend to carry vibrations further from the source.
Human Perception vs. Potential for Building Damage
It is important to note that people and buildings react differently to vibration.
While a person might be able to feel vibrations, it does not mean that damage to
building elements has occurred. Although tolerance levels vary considerably,
people are much more sensitive to vibrations than buildings. A person may be
able to feel vibrations that are 50 times less than the level of vibration typically
estimated to cause damage to a building or its structural components.
Construction vibrations expected under this project are more of a nuisance than
a cause of property damage. The vibrations are not expected to reach the levels
that can cause damages to homes or buildings.
Vibration Monitoring
In recognition of the potential for production of vibrations from the construction
work, Minto has implemented a vibration monitoring program to monitor
construction induced vibration levels. Vibration monitors have been installed at
adjacent properties within close proximity to the construction site. The vibrations
are monitored on a continuous basis and the contractor is required to carry out
the work in a manner to keep the vibrations, as monitored by the instruments,
below acceptable levels. The acceptable threshold of vibration levels for this
project is very conservative and are in line with the industry standards to prevent
damage to nearby properties and homes.
Vibration Levels
People (and animals) are very perceptive to a small amount of vibration.
However, without scientific instruments (seismographs), people cannot
accurately place a value on the amount of vibration generated. Human
perception of vibration is around a peak particle velocity (PPV) of between 0.2
mm/s and 0.5 mm/s. By comparison, the industry accepted PPV for residential
structures is 50 mm/s for frequencies above 40 Hz. A door slamming,
thunderstorm activity and wind all produce vibrations that we feel but are ignored
since these are “everyday” events. The acceptable PPV levels for this project
were set at 5 mm/s for frequencies less than 10 Hz and 5 mm/s to 45 mm/s for
frequencies between 10 Hz and 40 Hz (sliding log scale).
Pre-Construction Surveys
Pre-construction surveys were offered to homeowners with a building or structure
within 30 meters of the work zone. The objective of the pre-construction surveys
is to document the state of the buildings and structures prior to commencement
of construction for the purpose of documenting a baseline and resolving possible
claims by residents or building owners located in the vicinity of the construction
site. If you are more than 30 meters from the work zone and you are concerned
about vibration damage, you may wish to complete your own pre-construction
condition survey of your property. Your survey should include dated photographs
and / or video. Construction will be ongoing until the fall of 2025. It is not too late
to complete a pre-construction survey.
Cracks Do Not Equal Damage
Cosmetic cracks do not necessarily mean there is structural damage. The
average person is not aware of the stresses that a home in Canada must endure.
The Building Code requires that homes be designed to be flexible to try and
accommodate these stresses. There are many reasons for appearance of
cracks. Shortly after a new building is constructed, cracks may appear due to
drying of construction materials. In older buildings, cracks often occur as a result
of extreme environmental conditions or simply aging materials. They may also
occur due to the building settling and adjusting to external forces caused by
environmental factors.
The foundation is the strongest part of a house. Ground vibrations intense
enough to crack foundations consisting of concrete and masonry would have to
greatly exceed the accepted vibration levels for this project.
Suggestions to the Homeowner
To reduce the frustration from construction vibration you may wish to:
- Separate items in china cabinets or other display cases;
- Place tissue paper between stacked dishes such as cups and saucers;
- Ensure that furniture is not touching the walls of the home; and,
- Check picture frames and wall-hangings to ensure they are secure.
We thank residents and homeowners for their continued patience during the
construction period.
Frequently Asked Questions
Q1: Are construction induced vibrations worse in the winter?
A1: Soil conditions, particularly the frost layer in winter and the level of ground
water table, may influence the level of induced vibrations. However, the extent of
this influence is not clear. In a study of vibrations induced by buses in Winnipeg,
Sutherland (1950) reported that vibrations measured in winter, while the topsoil
was frozen, were significantly less than those measured in summer. On the other
hand, subway-induced vibrations in buildings that were measured more recently
in Toronto were found to be slightly higher in winter (while the topsoil was frozen)
than in summer. Officials of many cities in Canada indicate that vibration
complaints are more frequent during the thaw period in spring than in other
seasons.
Construction induced vibrations may vary depending on the soil conditions at any
given time of the year. However, vibrations dissipate at a rapid rate as they
radiate out from the source (i.e. construction site). In order to mitigate and control
these vibrations, monitors have been installed at several properties within close
proximity to the construction site to ensure that vibration levels are within the
project limits at all times.
Q2: Does the duration of vibration have an impact on the likelihood of
building damage?
A2: If the vibrations remain under the accepted levels, building damage is
unlikely, regardless of the vibration duration.
Q3: Why aren’t you using smaller equipment to reduce vibrations?
A3: For some work, using smaller equipment is not an option. For other works,
using smaller equipment is possible but the construction would take much longer.
Our consultant has selected the vibration limits to allow the contractor to carry
out the work within a reasonable time period while minimizing the potential for
damage to homes. Our consultant and contractors are monitoring vibrations to
keep them within acceptable limits, while trying to balance the need to minimize
the construction duration and, by extension, the length of construction disruption
to residents of the adjacent neighborhoods.
Q4: Could I get the results of the vibration monitoring?
A4: Because the vibration monitoring is continuous and includes multiple
monitoring points, the amount of data collected is extensive and not practical to
share. The highest vibration level of a specific date and location can be shared if
requested.
Q5: What do I do if I find damage?
A5: Minto Communities Inc. and General Contractor, Robert Excavating Ltd. are
required to carry liability insurance for this project. If you find damage, email your
claim to Jean-Michel Le Blanc (Minto) jleblanc@minto.com with a description of
the damage, photos and contact information.