Finger Lakes Building Officials, Inc.

An Affiliated Member of the New York State Building Officials Conference

Code Snippit

Ready for another, now that the building season is here? The following excerpt is from the Residential Code:

§RR802.11 Roof tie-down.

§RR802.11.1 Roof tie-down. Roof assemblies subject to wind uplift
pressures of 20 pounds per square foot (0.958 kN/m2) or greater, as
established in Table RR301.2(2), adjusted for height and exposure per
Table RR301.2(3), shall have rafter or truss ties provided at bearing
locations in accordance with Table RR802.11. A continuous load path
shall be provided to transmit the uplift forces from the rafter or truss
ties to the foundation. Wind uplift pressure on roof assemblies shall be
determined using an effective wind area of 100 square feet (9.3 m2) and
Zone 1 in Table RR301.2(2).

If you go through the exercise (and it's worth doing), you come to the conclusion that most low-pitch roofs (under 3/12) have to be tied down in accordance with the requirement. Those of you near the lakes or in wide open spaces may have roofs with slopes greater than 3/12 which have to be tied-down.

The bad part of all this is that it is almost area specific and there is no universal standard like "do it in all cases", so you, as CEOs, have to make those determinations for each of your permit applications, or require the design professionals to do so.

Dick Thomson

Finger Lakes Building Officials Association, Inc.
3100 Atlantic Ave.
Penfield, NY 14526