Smoke alarm question

The minimum requirement is smokes in escapes routes only unless it has changed very recently. 

I offer heat detector in other rooms and leave it up to client to decide.

Not done any new builds with solar but did a job a couple of years ago with batteries in the roof of a single storey part of house and they wanted a smoke detector up there.

Gary

The LD2 system requires all escape routes, plus kitchen and most habitable room (living room.)

Presumably heat rather than smoke in the kitchen - otherwise it'll be false alarm city Arizona...

   - Andy.

goldenboy1818 said:

most habitable

Dry, warm, and draught-free?

I too attended an Aico day this week - very polished!

So BS 5839-6, etc. 3.28 habitable room any room in a dwelling other than a kitchen, utility room, bathroom, dressing room [sic] or WC.

3.47 principal habitable room habitable room (see 3.28) that is normally the most frequently used room for general daytime living purposes

That is where I struggle - by whom are these rooms occupied? We no longer have the family gathered around the fire in the front parlour reading, and listening to gramophone records. Take my daughter's home (Ma & Pa & 2 school-age girls.) The kitchen (with 'dining area') is where the family probably spend most time together, but that is not a habitable room!

Ma & Pa have their own offices and do some work in the evenings. The little girls do their home work after dinner. So multiple rooms are used most frequently. Perhaps they should all have fire detectors?

If in doubt, I suppose put one in. :-)

goldenboy1818 said:

Also with solar would you put a smoke in a loft, this wasnt really covered. A solar team told me only if its covering the battery but the aico guy seemed to say if anything was up there including the inverter 

I asked about "loft space" - BS 5839 offers no definition. However, it says, 11.1.1 Category LD systems ... In 2019 it is increasingly common for electrical equipment to be installed in loft spaces, particularly in premises fitted with photovoltaic power systems and other plant (e.g. boilers). In such cases, a Cetegory LD2 system needs to incorporate a smoke detector within the loft space.

We discussed, the meaning of, "loft space". We concluded that it is a space beneath the roof which can be entered by an ordinary door or hatch-door, etc. However, if there are vertical partitions, the eves space on the other side is not part of the loft space.

Personally I would recommend a interlink smoke/heat alarm in every loft regardless of PV or inverter being present.  The main reason is the fire COULD start next door and spread over the roof very easily and very quickly.  If you do some internet searching you will be able to find footage.  It is also something the UK home insurance industry are looking at as a recommendation.

Sergio Fernandez said:

the fire COULD start next door and spread over the roof very easily and very quickly

Yes in a terrace or semi-detached, but unlikely with detached properties.

It is a good point, though. The neighbours' standards of maintenance may not be what one would desire.

goldenboy1818 said:

Also with solar would you put a smoke in a loft, this wasnt really covered. A solar team told me only if its covering the battery but the aico guy seemed to say if anything was up there including the inverter 

Yes, also LD1 system ... although with any category of system BS 5839-6 recommends that where any electronic equipment (and an inverter is given as an example) is installed in locations that are not frequently visited (lofts are given as an example), detection is provided. Clause references in BS 5839-6 as follows that cover this issue:

• LD2 system, Clause 11.1.1 recommends Category LD2 systems to incorporate a smoke or multi-sensor detector in lofts.
• LD1 system, Clause 11.2 g) recommends smoke or heat detection to be installed in lofts in Category LD1 system
• Any category of system: Clause 11.2 p) recommends smoke, heat, or multi-sensor detection/alarm where PV power systems, boilers and UPS systems are installed in loft spaces.

I do wonder about the practicality of these standards, yes clearly you would want some form of fire detection in an unoccupied space like the loft where the equipment presents the risk of a fire starting and going undetected, but if the loft space is uninhabited, so a regular loft subject to dust, insects and extreme temperatures, then the practicalities are far from straightforward.

The standards propose smoke alarms, but read any manufacturers instructions for a smoke alarm and typically they all state that smoke alarms should not be used in spaces subject to dust, insects or temperature extremes, so basically unsuitable for use in a loft space because of the risk of false triggering. So the standards call for smoke alarms, but actually most smoke alarms are not suitable for lofts.

Heat alarms are more immune to dust and insects, but even then they are designed for ambient temperatures in habitable spaces and some of the maximum ambient temperatures for heat alarms provide little or no margin for the potential hot summer temperatures you might find in a loft, making false triggering a potential problem even with heat alarms.

And of course if a heat alarm in a loft does incorrectly trigger, it's not always trivial to reset it, cool it down to stop it re-alarming, the poor old householder is actually in a something of a pickle for how they stop their interlinked alarms going off. I wonder if it needs something more robust, like availability of heat detectors purposely designed with increased temperature ratings for a loft space.