13.07.2015 Views

47.5 MB - The Whole Building Design Guide

47.5 MB - The Whole Building Design Guide

47.5 MB - The Whole Building Design Guide

SHOW MORE
SHOW LESS
  • No tags were found...

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

Edge flashings and copings: If cleats are used for attachment, it isrecommended that a “peel-stop” bar be placed over the roof membranenear the edge flashing/coping, as illustrated in Figure 3-91.<strong>The</strong> purpose of the bar is to provide secondary protection againstmembrane lifting and peeling in the event that edge flashing/coping fails. A robust bar specifically made for bar-over mechanicallyattached single-ply systems is recommended. <strong>The</strong> bar needsto be very well anchored to the parapet or the deck. Dependingon design wind loads, spacing between 4 and 12 inches on centeris recommended. A gap of a few inches should be left betweeneach bar to allow for water flow across the membrane. After thebar is attached, it is stripped over with a stripping ply.Figure 3-91:A continuous peel-stop barover the membrane mayprevent a catastrophicprogressive failure if theedge flashing or coping isblown off. (Modified fromFEMA 55, 2000)Walkway pads: Roof walkway pads are frequently blown off duringhurricanes (Figure 3-92). Pad blow-off does not usually damagethe roof membrane. However, wind-borne pad debris can damageother building components and injure people. Walkway pads aretherefore not recommended in hurricane-prone regions.3-112 MAKING CRITICAL FACILITIES SAFE FROM High Wind

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!