DCN ARCHIVES

December 21, 2012

JIM JENNINGS, CANADIAN ACADEMY OF BUILDING SCIENCES INC.

A roofing blooper was discovered recently when an attic was invaded by raccoons. Rather than strip the shingles from an old roof, builders had constructed a new section of roof entirely over an old set of shingles.

How to avoid construction bloopers

Construction projects often bring out the best in people. Occasionally they bring out something less.

James Jennings, chief executive officer of the Canadian Academy of Building Sciences Inc. and Ian Shaw, director, Soil-Mat Engineers & Consultants Ltd., have collected photographic evidence of some of the most egregious construction bloopers they’ve encountered. They were recently presented at a session of the Construct Canada show in Toronto.

“When they start stripping asphalt off the roof and I see something awful, I discretely take out the camera and add it to the collection,” says Jennings. “Of course the names and faces have been obscured to protect the ignorant, greedy or lazy.”

While the photographs may elicit chuckles, the presenters say they also hope contracting professionals will be educated to avoid similar sub-standard work.

“Although we might be quick to laugh, at the other end of the joke is a disgruntled project owner, occupant or taxpayer,” says Shaw.

He recalls a project in which a building was being converted to lofts with the promise that several additional floors would be built on top of the existing structure.

“They had already sold the project based on unit pricing then called us for a geo-technical report,” says Shaw. “We had to tell them that the existing condition of the building could not support the additional floors. Three-quarters of a million dollars later they were finally ready to go — a cost they could have avoided if they’d called us six months earlier.”

Another project involved site work completed in December, in which bulldozers compacted earth over six inches of snow.

“Eight months later the steel erectors walked off the job because they couldn’t put the steel in place,” he says. “They had to put the steel structure on wheels and roll it away as a new foundation and footings were laid. When they dug test pits, they still found the snow buried deep underground.”

Shaw recommends that contractors read geo-technical reports whether they appear to apply to them or not. Owners should make certain that any engineering tests specified in the document are actually carried out.

Jennings’ current collection focuses primarily on roofing bloopers.

He says he’s witnessed many cases where contractors claimed that strips of plastic left under shingles would “melt over time.”

Roof torching has also been claimed as a cure-all.

“Owners were told that the plastic film left underneath the roofing material would melt when the surface was torched,” he recalls. “They’ve been told that wet roofing materials or water trapped between sheets of bitumen would dry out after torches were applied.”

Jennings says he has also seen roof patches on top of patches, and over-torqued screws in metal roofs that tore through gaskets.

“I’ve seen screw holes so big that I could see sunlight filtering into the inside of the building,” he says.

Other errors involve gaps in sloping roof materials. Jennings notes that a gap the size of a credit card, even if protected by down sloping and overlapping roofing materials, will still result in leaks.

“Wind-driven rain will force moisture through that gap uphill,” he says.

Jennings says that considerable time, effort and money could be saved if contractors, consultants and designers ironed out misunderstandings about project design and specifications early in the project. Contractors should also speak up if they believe they’re being asked to follow instructions that will take the project to an unhappy conclusion.

Jennings notes that he isn’t singling out the roofing industry for generating an inordinate number of bloopers.

“The next time I make this presentation, I’ll have my slides of improper high-rise balcony work all sorted out,” he says.

Print | Comment

MOST POPULAR STORIES
TODAY’S TOP CONSTRUCTION PROJECTS

These projects have been selected from 415 projects with a total value of $3,354,507,550 that Reed Construction Data Building Reports reported on Tuesday.

HOSPITAL ADDN/ALTS

$200,000,000 Milton ON Tenders

HOTEL

$55,000,000 Ottawa ON Negotiated

SOLAR FARM

$30,000,000 Lennox and Addington Co ON Negotiated

Daily Top 10

CURRENT STORIES
TODAY’S TOP JOBS

Project Manager
Ontario-Oshawa

Estimator
Ontario-Toronto

Site/Field Coordinator
Ontario-Mississauga

Superintendent
Alberta-Red Deer

Operations Foreman
British Columbia-Vancouver

Earthworks Estimator
Ontario-King

Junior Construction Manager
Alberta-Fort McMurray

Estimator/Project Manager
Ontario-Gormley

Machinist
Alberta-Edmonton

Heavy Duty Mechanic
Alberta-Edmonton

More jobs 

myJobsite.ca

Your gateway to
the top careers
in construction
and design