We used to have a caveat in our Building Code that allowed 4 head design with QR's if smokes were in the space. With residential heads, we can omit smoke detectors in the bedrooms but they must be in the Hall or vicinity of the room, by code. If we put the smokes back, we could use QR heads, like dry pendents. I don't recall it as a standard exemption but a code exemption.
Tom Duross Go Red Sox P.S. Just looking at this job now, and asked the FM what they required is how this started. Looking closer at the plans means 3000 Sf design area for combustible construction too. Your right we would have to use 1500 as the starting point for a dry design, and now 3000. Thom McMahon > Area reductions do not apply to dry systems. Second, the 4 head rule is > under 11.2.3.5 Residential Sprinklers. So unless it's a listed residential > sprinkler, I don't see how you can apply the 4 head rule to QR heads. > > Joe Burtell, SET, CFPS > > > Bill: > > 2007 discusses the shadow area and I think the area allowed for Res. is 6 > SF, if you attended Roland's and Chris's presentation on the 2007 > standards > at convention last Sept. this was in the notes. > > New Question: > Residential 13 occupancy. With residential heads this is a 4 head design, > however I have had an AHJ say that even if you use QR in a Residential > occupancy that it stay's a 4 head design. I've always used room design or > area density in residential occupancy's for which we had to use QR heads > for > > some reason. Have I been wrong all these years? > > Example: Needed to run a dry attic location to feed QR dry Pend. in > residential occupancy. 10 foot ceilings we use 900 Sf and increase by 30% > for dry. He say's that we only needed to calc 4 heads, and uses NFPA 13, > 1996 Fig. A-5.3.2.2 "Examples of design areas for dwelling units." > Shows 4 heads different configurations. > > Any thoughts? > > Thom McMahon > >> Another obstruction question related to residential sprinklers. >> >> Figure 8.10.7.2.1.4 (2002) shows a sprinkler obstructed by a column. >> Assume >> a 16' x 16' coverage area from a sidewall residential sprinkler and a 12" >> x >> 12" column located 4' from the face of the column. I calculate a 29 sq >> ft >> shadow area behind the column. >> >> Is this a correct interpretation of the Figure? If so, is it possible to >> shift this shadow area to another part of the room to show equivalent >> protection? Is it appropriate to have 11% obstructed area in a 16' x 16' >> room? >> >> Since I'm on the subject of obstructions, what method should be used to >> cover bunk beds? Is furniture excluded? Bunk beds were last mentioned >> here >> in October 2002 but not with respect to the obstruction hazard. >> >> Bill Brooks >> Pittsburgh, PA _______________________________________________ Sprinklerforum mailing list [email protected] http://lists.firesprinkler.org/mailman/listinfo/sprinklerforum To Unsubscribe, send an email to:[EMAIL PROTECTED] (Put the word unsubscribe in the subject field)
