Roof Anchors / Reinforcing Steel Structure

In Ontario, Canada most high rise buildings, residential and commercial, are constructed with reinforced concrete floors and columns.  On shorter buildings, usually commercial, industrial or schools, the roof structure is steel and comprised of beams and joists. When permanent fall protection systems are installed on this type of roof structure, often the locations are required to be reinforced. The reinforcing method typically used is whats called an "H-frame". See this article written by Canam for more information: http://www.canam-steeljoist.ws/www/v4/newslet.nsf/va_redir/joistv5n2

A few common issues with reinforcing are

• anchor locations are not shown on the structural drawings
• anchor locations do not show reinforcing on the structural drawings
• reinforcing responsibility is not clearly assigned to a scope of work in the specifications
• reinforcing methodology is not clearly detailed in the drawings

When the specifications are written and reinforcing of roof anchor locations is not addressed, a number doesn't get carried at the time of tender and the result is a hefty extra to the building owner or general contractor.

Another common situation is when the architects put the reinforcing into the window washing / fall protection manufacturers scope of work.  When this happens and reinforcing is not detailed, the window washing manufacturer may price the reinforcing and get the contract, but at the end of the day when shop drawings are submitted the structural steel trade may reject the methodology and the result is dispute over who pays for the extra.

Architects can save time, confusion and money by ensuring that they:

• consult a structural engineer on the issue of reinforcing of the roof structure
• show the anchors on both the architectural roof plan and structural roof framing plan
• show the locations of reinforcing on the framing plan
• detail methodology of reinforcing in the drawings
• clearly assign the reinforcing scope of work to the structural steel trade in both their spec, and the fall protection manufacturers spec

In Ontario we generally require the roof structure to be reinforced to a 5,000 lbs ultimate load. For new construction, leave the anchors to the anchor guys and structure to the structural guys.

Michael Gray
Marketing and Sales Support
Ontario and Eastern Canada
Pro-Bel Enterprises Ltd
e: mikegray@pro-bel.ca
t: @Pro_Bel