Pir Positioning Advice And Best Practices

[kuchars22]

I've attached a plan layout of our home. I am particularly interested in setting up a PIR for the living/dining room to protect the front bay windows. However, reading the DIY install guide, it was mentioned that the PIR should not face a bay window. If I was to place the PIR located on the image shown in green, this will face the opposite end of the room (it would also cover anyone entering from the rear of property) However, I'm concerned that this location won't cover the bay window where someone would enter the front window, as the window is set back from the corner of the room. The PIR shown in red would cover it, but would violate the advice about facing the front bay window. The length of the living/dining room is about 7m. How else could I place the PIR, or do I simply get the front windows protected with window contacts? I have a honeywell DT PIR if that's any help.

Same for Bedroom Two, the windows to this room are easily accessible by climbing on the flat roof of the kitchen. The room is already decorated so I don't want to wire detectors there. I either have the option of RF contacts on the window or PIR facing the window - which is best?

One final thing, is it best practice to have at least 2 detectors covering an entrance (ie. door contact and PIR facing the door), or would one PIR normally be enough providing it covers the entrance?

Thanks

[arfur mo]

best position for detector is decided by many factors, refer to the enclosed advice sheets that coe with them.

we can not decide for you as we have no idea of the valuables contained within your home, or factors like drainpipes leaded windows or environmental problems which could cause false alarms like radiator positions.

if we were to put our name to your design we then have a duty of care to you, so if you unfortunately got turned over and the alarm did not cover the area intruded, we could be held accountable and so sued, and this although no money ever changed hands.

above as advised by NSi inspector on IFSEC stand (after switch spur fiasco).

regs

alan

[kuchars22]

best position for detector is decided by many factors, refer to the enclosed advice sheets that coe with them.

we can not decide for you as we have no idea of the valuables contained within your home, or factors like drainpipes leaded windows or environmental problems which could cause false alarms like radiator positions.

if we were to put our name to your design we then have a duty of care to you, so if you unfortunately got turned over and the alarm did not cover the area intruded, we could be held accountable and so sued, and this although no money ever changed hands.

above as advised by NSi inspector on IFSEC stand (after switch spur fiasco).

regs

alan

Thanks for that. My PIRs haven't arrived yet so I can't consult the manual.

[magpye]

Thanks for that. My PIRs haven't arrived yet so I can't consult the manual.

If it helps you thinking while you are waiting for your PIRs to arrive, in general it is normal to position these so movement is across the detection pattern, not towards the detector, but make sure you consult the manual for the models you will be using.

[Guest anguscanplay]

best position for detector is decided by many factors, refer to the enclosed advice sheets that coe with them.

we can not decide for you as we have no idea of the valuables contained within your home, or factors like drainpipes leaded windows or environmental problems which could cause false alarms like radiator positions.

if we were to put our name to your design we then have a duty of care to you, so if you unfortunately got turned over and the alarm did not cover the area intruded, we could be held accountable and so sued, and this although no money ever changed hands.

above as advised by NSi inspector on IFSEC stand (after switch spur fiasco).

regs

alan

I`m going to bookmark this post for when we get snowed in - talk about taken out of context LOL

Dont be worrying - all ours for 30 years have been looking at windows

[magpye]

Dont be worrying - all ours for 30 years have been looking at windows

Couldn't let this one go now could I?

30 years and no problem with PIRs looking at windows, wow, where are all your installations, down coal mines? So you just have bat problems.

Have had a house with intermittent F/As over a couple of years, only during the early summer afternoons. All the usual checks made, equipment replaced etc, still happened.

Now this was an audible only system that had been installed for many years with no problems whatsoever, changing the make of detector was a no no because of the clients insistence that the decor will not be compromised - (nicely).

One day I was two doors away servicing their keyholder's alarm, we heard it go off, away we went, could find no problems - until we went into the south facing sittingroom.

Here we found a 'hot spot' from the sun about 4" away from the PIR in a rear corner so the detection pattern was across the window area, this was caused by reflection from the sun via the glass topped and shelved coffee table with glass paperweights, when a clouds passed the hot spot came and went.

The position of the coffee table was adjusted so that the sun would cross the PIR again, guess what happened, cloud, activation.

We found out the coffee table was a new acquisition, year before the F/As started - moved table position - here we are years later and no more F/As.

Why do manufactures of PIRs all say do not position looking at windows, or similar?

I guess having all your PIRs looking at windows means that it's easier to run cable around the landing and drop to the nearest convenient corner below rather than cable around the bedrooms etc?

[Guest anguscanplay]

Couldn't let this one go now could I? resist making myself look foolish now could I

Why do manufactures of PIRs all say do not position looking at windows, or similar?

I guess having all your PIRs looking at windows means that it's easier to run cable around the landing and drop to the nearest convenient corner below rather than cable around the bedrooms etc?

Manfs. dont ALL SAY DO NOT - thats a sweeping statement

How many jobs you actually installed? cant think of many houses where the landing is bigger than the downstairs hall

point is ( as shown by your example) for every thousand you fit one or two might lead to false alarms and your going to get those false alarms from that enviroment anyway ( move the coffee table and start getting reflections from the mirror ?) real world it doesnt matter wether you site it on an inside , outside or upside down wall - buying good reliable sensors and cabling properly is more important.

Angus

ps - we only fit dueltechs LOL

[magpye]

Dont be worrying - all ours for 30 years have been looking at windows

(ps - we only fit dueltechs LOL)

We are talking about PIRs NOT DualTecs, apart from that DualTecs were not around 30 years ago

"Manfs. dont ALL SAY DO NOT - thats a sweeping statement"

- perhaps they don't say it but there will be a little picture with a cross in one corner, means the same thing.

[Guest anguscanplay]

(ps - we only fit dueltechs LOL)

We are talking about PIRs NOT DualTecs, apart from that DualTecs were not around 30 years ago

"Manfs. dont ALL SAY DO NOT - thats a sweeping statement"

- perhaps they don't say it but there will be a little picture with a cross in one corner, means the same thing.

humour lost on you isnt it maggy, you can try and argue this all week till Xmas if you want - my little picture also show a radiator with a cross in one corner, we tried getting people to take them out of the lounge but they all complained it was cold.

the installer guide is just that - a guide for people who dont really get what they are doing

[topalarms]

PIRs facing areas of external glazing is not good practice.

PIRs facing heat sources is not good practice.

Fact it doesnt always cause problems doesnt make it good practice.