It’s an exciting time for us at Davies Smith Developments. This week we demolished a portion of the Eleven Superior sales centre, as we prepare for construction to commence soon. In his latest Construction Management 101 post, Graham Chalmers explains what goes on during the demolition process.

The whole process of demolition from the initial stage of preparing the paper work to the active demolition stage, takes approximately 3-4 months. There are usually 3 steps involved.

Permitting

Before we begin demolition, we need to first make sure that we have received all of the necessary permits. The permits include: a demolition permit, a temporary entrance permit and a hoarding/covered walkway permit.

Once we’ve received all the permits, we then give the utility companies advance notification prior to demolition. For example, when requesting to disconnect gas and to remove existing meters and infrastructure, Enbridge Gas requires 44 days from the date of creating the work order.

Abatement

The next step is the abatement process. This involves removing hazardous, unwanted or unregulated items in the building prior to active demolition.  For example, removing asbestos, lead, mercury, mould, ozone-depleting substances, bird droppings, rodent baiting etc.

Demolition

When we’re ready to begin demolition, we develop a demolition methodology report and site-specific safety and work plans before we proceed.

A demolition methodology report is prepared by an Engineering firm and it explains how the building(s) will be demolished.  The main purpose of this report, is to forecast the safest and most logical way to deconstruct a structure.  It will explain certain structural elements to eliminate first, which leads to how the building will fall and in which direction. In demolition, the direction a building crumbles/falls is very crucial in order to ensure safety for the surrounding area and men on site.

Next, we prepare site-specific safety and work plans. This is a critical planning step in the process to ensure the safety of the public and workers on site during the demolition. Typically, a Construction Management Plan and a Traffic Control Plan are created for City approval.

A Construction Management Plan includes location of site protection, such as construction hoarding, fencing, overhead scaffold and wood covered walkway; location of construction trailers; location of staging area for concrete trucks and steel trucks; storage area; trade/staff parking area; vehicle access gates; location of tower crane and swing boom radius; and location of temporary hydro box.

The Traffic Control Plan includes information on road lanes and sidewalks that need to be temporarily closed for the duration of construction. It illustrates what traffic signs and measures are to be used during public right-of-way closures. Traffic flag men and police officers are also used in these types of situations.  Regulations are dictated by the Ontario Traffic Manual Book 7.

During active demolition, we use either hydraulic excavators or high-reach demolition excavators. Hydraulic excavators are usually used to demolish 1 to 2 storey buildings and the excavator is operated by a liquid moving in a confined space under pressure.

High-reach demolition excavators are used for taller buildings where explosion is inappropriate or not feasible. This machine tears down the structural components. The operator of the machine will do this in a way to control the direction of how the building will fall.

Throughout the demolition process, dust is controlled to prevent the technicians working on the site as well as local residents from inhaling hazardous dust. This includes daily wetting of all hard and soft surfaces and exposed areas of soil, daily cleaning of road pavement and sidewalks and cleaning of all trucks before leaving the site, etc.

With extensive knowledge in the field, Graham Chalmers was initially groomed as a Construction Superintendent before taking the lead as Construction Manager for such reputable companies as Ronto Development, Edifice Group Mollenhauer, and Daniels. Graham then went on to spearhead and oversee the construction and development team at Davies Smith Developments .