9.9.4.6. Openings Near Exit Doors

 9.9.4.6. Openings Near Exit Doors

This Article specifies where unprotected openings have to be protected when located near exit doors to reduce the risk of a fire breaking out through a window and exposing an exit door to heat, making it unsafe as an exit. 

Exterior exit doors can be exposed to fire from unprotected windows in other parts of the building, which may interfere with the evacuation of the occupants in the event of a fire. Unless the exposing windows are kept at a substantial distance away and at a reasonable angle of exposure, they should be protected with wired glass or glass block (Figure 9.9.-5).

Quoted from Illustrated Users' Guide - NBC2015

#openings #windows #building #exit

Why is it important to have a third party plans review?

There are two simple reasons by human nature:

1. the designer never knows that he/she made a mistake.

2. the designer never wants the others to know that he/she made a mistake.

This is why plans done by one designer should be reviewed by another in a well organized design firm and an important project design done by one design firm should have a peer review by another design firm.

Are we happy to invest a project without third party plans review?

#project #designer #thirdpartyplansreview

A secret of plans review at AHJ

 A secret of plans review at AHJ

It is always a great thing for designers and building owners to have their plans approved by the AHJ, but one thing the plans reviewer would never tell us is what is not required on the plans.

Recently, there was a 4 unit rowhouse. The contractor asked me if it is sufficient for him to provide sprinklers in the basement only. After reviewing the approved plans, I found the designer specified that the whole building will be sprinklered. I am speechless. No one plans reviewer at the AHJ would tell us that more than $60k for the sprinkler system is not required for this building.

#building #designers #plansreviewer #sprinklers

9.9.4.5. Openings in Exterior Walls of Exits

This Article specifies where any opening has to be protected to reduce the risk of fire breaking out through a window in one fire compartment and exposing the window openings in an exit stairway to sufficient heat to break ordinary glass, rendering the exit unsafe.

Windows in the exterior wall of an enclosed exit can be exposed to fire from windows in an exterior wall of another part of the building. Windows in the same plane as the exit windows are not considered to be an exposure hazard. Windows at an angle of less than 135° located within 3 m (9 ft. 10 in.) horizontally and less than 2 m (6 ft. 7 in.) vertically to each other are considered a hazard (NBC Article 9.10.12.3.). For this reason, either openings in exterior walls of an exit or openings in adjacent exterior walls of the building must be protected with wired glass or glass block (Figure 9.9.-4).

Quoted from Illustrated Users' Guide - NBC2015

#building #openings #windows

9.9.4.4. Openings Near Unenclosed Exit Stairs and Ramps

 9.9.4.4. Openings Near Unenclosed Exit Stairs and Ramps

This Article specifies where unprotected openings in exterior walls have to be protected to reduce the risk of fire breaking out through a window and interfering with evacuation from an exterior exit stairway or ramp as a result of excessive heat radiation.

Exterior unenclosed stairs or ramps are also vulnerable to exposure to fire from openings such as windows. Openings located close enough to be an exposure hazard must be protected with wired glass or glass block (Figure 9.9.-3) if the exterior stairs or ramps are the only means of escape.

Quoted from Illustrated Users' Guide - NBC2015

#openings #stairs #ramps #windows

9.9.4.3. Wired Glass or Glass Block

 9.9.4.3. Wired Glass or Glass Block 

This Article provides the requirements for the properties and size of wired glass and glass block that are used to reduce the risk of heat radiation from a fire on a floor area that can make an exit stairway unsafe for evacuation if the exit is not shielded by a fire-resisting vestibule.

Glass block or wired glass can withstand the effects of fire long enough to permit its use as a closure. Large glass areas, however, can expose the exit user to radiation from fire in the adjacent floor area. For this reason, the area of glass in the doors of an exit (and any adjacent sidelight) must be limited, unless the exit door is protected by an enclosed corridor or vestibule separated from the floor area by fire separations having not less than a 45 min fire-resistance rating (Figure 9.9.-2).

Quoted from Illustrated Users' Guide - NBC2015