The Fix for Fire Safety

 18/12/24

Before and after views of bedroom 3 in B apartments

There are three major fixes planned for Herbert Gardens.

There is the strengthening to +40% of the New Building Standard, attention to weather tightness (those leaks!) and bringing the building up to fire safety standards.

This last, as we have learned, is going to affect the third bedroom in all B apartments.

And here is the nitty gritty from Max of Studio Pacific Architects.

One of the most important life safety upgrades planned in the upcoming works is addressing the vertical spread of fire between apartments on different levels. Currently, the south-facing window in Bedroom 3 of the B-Type apartments does not meet the NZ Building Code requirements to stop the vertical spread of fire, as there is not enough vertical separation between the windows. Other windows throughout the building are protected by the projecting ledges between floors. The Building Code requires a vertical separation of 1.5 metres between windows. Currently  there is a vertical separation of 1.140 metres between the B-Type apartment Bedroom 3 windows. 

 

There are two options to address this issue:

 

1. Install a fire rated window in place of the existing window
2. Install a non-fire rated window in place of the existing, with a higher sill to achieve the required vertical separation of 1.5 m between windows, and a fire-rated spandrel constructed below.

 

Fire rated windows are expensive and have specific requirements regarding openable windows, along with thicker frames and glazing. A typical window suite cannot be used as a fire rated window. Given the expense and restrictions of fire windows, the decision was made to proceed with option 2, and replace the Bedroom 3 window with a non-fire rated window and increase the spandrel height to 1.5m between windows.

 

The new window has been designed to match the appearance and proportions of the existing windows in the building. Below the new window will be two opaque glazed panes, concealing the fire rated spandrel which sits below the window. An external visualisation of these windows are attached in SK.104.

 

The fire-rated spandrel constructed below the window will be constructed of timber framing with a fire-rated plasterboard wall lining. When complete, internally this will look exactly like a typical plasterboard wall.

 

The approximate dimensions of the new window are as follows:

 

• Slab to existing window sill: 0.98m
• Slab to new window sill: 1.37m (raised by 0.39m from existing)
• Carpet to new window sill (assuming 20mm thick carpet and underlay): 1.35m 
• Size of new entire window: 2.47m (wide) x 2.55m (high)
• Size of new glazed window: 2.47m (wide) x 1.2m (high)