Hi. I am working on a project where the owner has split a 1930s semi detached house into two flats. There is a communal front door which leads to a small (about 2m x 2m) hall, which has two front doors to each flat. 

Above each of the internal "front" doors is an opening that is roughly the width of the door, and about 40cm high. The owner is hoping to glaze these two openings with some sort of double-glazed glass units.

This is to let some natural light in to the individual flats. The doors are FD30, but we have had no guidance from the architect on speccing this glass opening. My understanding is that is needs to be fire resistant glass (to 30 mins, as per the doors).

In terms of fitting, if we purchase a 30 minute fire rated sealed unit and packed it into place using 30 minute intumescent tape, siliconed in with a fire proof silicone (e.g. Dow Corning Firestop 700), would this be sufficient? Are we thinking along the right lines here? 

 

Thanks! 

You should purchase the glass, gasket materials and glazing beads (retention system) as a complete system.  Example of a fire rated glazing system below:

1) FR glass product, 2) gasket/setting system, 3) beading system, 4) fixings (including sizes and centres) and 5) framing.

Start by selecting a suitably fire rated glass and consult the relevant fire resistance performance certification for details of the gasket/beading/fixings system that is necessary to suit that particular glass. Various certifications can be found at   https://www.warringtoncertification.com/certified-companies/certifire/glass-and-glazing  for example.

Thank you, it's reassuring that such a 'system' exists, rather than trying to cobble something together ourselves. Thank you for the pointers - I will do some homework based on your advice.