Downlights in a thatched house

[yellowvanman]

Been asked to provide a rewire quote for a thatched cottage.

Customer asking for downlights in ceilings as headroom is quite tight! Ceilings are lathe and plaster and will probably be overboarded.

I suppose it could be done OK with LED downlights and firehoods, as there are also signs of mice would be best to install cable in metal trunking/copex.

Anyone have any reservations on this?

 

[telectrix]

use the low profile ( 50mm deep ) integrated LED fittings. think LEDHut do them. no need for fire hoods. as for the mice, get a cat. :ack2:

 

[davesparks]

Install whatever light fittings the client chooses, add firehoods to maintain the integrity of any fire barriers you break if the fittings are not suitably rated.

If you think rodent damage is likely to be a problem then yes use a wiring system which is rodent proof.

 

[Guest666]

Ditto.

 

[7029 dave]

Fire cans thats the way. If not bog standard pentands.

 

[gnselectricals]

Think the wiring system has got to be pyro, steel conduit/trunking anyway due to the thatch

 

[Leesparkykent]

Also might be worth checking with the building insurance company of the occupier to see what they spec.

 

[davesparks]

Think the wiring system has got to be pyro, steel conduit/trunking anyway due to the thatch

It may be specified by the buildings insurance, but there is no general requirement.

 

[spark 68]

Think the wiring system has got to be pyro, steel conduit/trunking anyway due to the thatch

Also might be worth checking with the building insurance company of the occupier to see what they spec.

Exactly what I was thinking .

 

[Engineer54]

Going by a family member that owns a thatched roof cottage in Essex, the insurance companies are very much interested in the properties electrical installation especially in the roof spaces. They all tended to want a fire resistant and fauna resistant system in the roof space. So i would definitely get your client to check with their home insurance company in the first instance!!

 

[D Skelton]

As above, you've got to go with insurance company requirements. If there are none, as a minimum I would be installing BS 8436 cable in roof spaces however I would be strongly recommending to the customer that they allow the installation of mineral. I would also be ensuring that RCD protection (300mA maximum) is installed to protect any cables run in the roof space. As for the downlights, no fire hoods needed. What will need to be specced however are LED downlights with separate drivers. It's all well and good installing rodent proof cabling in the ceiling space but what happens when they start chewing through the PVC flex feeding integrated lamps. I'd be terminating my mineral into enclosures which house the drivers within and running my ELV DC cables from there.

 

[yellowvanman]

As above, you've got to go with insurance company requirements. If there are none, as a minimum I would be installing BS 8436 cable in roof spaces however I would be strongly recommending to the customer that they allow the installation of mineral.

Why do you spec BS8436? Its not rodent proof according to one manufacturer I've contacted!

 

[yellowvanman]

Going by a family member that owns a thatched roof cottage in Essex, the insurance companies are very much interested in the properties electrical installation especially in the roof spaces. They all tended to want a fire resistant and fauna resistant system in the roof space. So i would definitely get your client to check with their home insurance company in the first instance!!

I've done a number of EICR for thatched properties, most of which have got T&E installed in the loft (old and new properties). Its my experience that the insurance personnel don't know a lot about the electrics. In a recent case they were wanting all Cat 3 observations to be fixed, most of which were due to changes in the regs (eg. 16th to 17th), and we tried and succeeded in educating them that sometimes its Ok for a Cat 3 observation otherwise you would be changing the consumer unit (eg) every 10 years or so!

On another note I can't understand why all this fuss sometimes about certain cables in thatched lofts, I've seen more damage from mice/rats under the floorboards.

 

[Guest77]

Install whatever light fittings the client chooses, add firehoods to maintain the integrity of any fire barriers you break if the fittings are not suitably rated.

If you think rodent damage is likely to be a problem then yes use a wiring system which is rodent proof.

What if they are 400 watt sodium fittings?

 

[D Skelton]

Why do you spec BS8436? Its not rodent proof according to one manufacturer I've contacted!

It's not rodent 'proof' so to speak, however fire risk is minimised due to the metallic sheath protecting the conductors within by having fault current carrying capabilities. An RCD with a maximum operating current of 300mA would also aid with fire prevention.

Unlike T+E, a rodent chewing through an RCD protected BS 8436 cable would simply just trip the device.

Like I said, insurance companies instructions need to be followed and in the absence of such instruction, as a minimum I would be installing this. Again, as I said, a strong recommendation would be made for installing mineral.

 

[D Skelton]

On another note I can't understand why all this fuss sometimes about certain cables in thatched lofts, I've seen more damage from mice/rats under the floorboards.

Because the treated timber above and the soil that is most likely to be below is unlikely to be easily combustible. With thatch, one unlucky spark and yer house is a gonner.

Would you run T+E in a hay barn???

 

[Guest77]

Been asked to provide a rewire quote for a thatched cottage.

Customer asking for downlights in ceilings as headroom is quite tight! Ceilings are lathe and plaster and will probably be overboarded.

I suppose it could be done OK with LED downlights and firehoods, as there are also signs of mice would be best to install cable in metal trunking/copex.

Anyone have any reservations on this?

Fire proof LED fittings would be my choice, the wiring would however be my concern, PVC/PVC and evidence of mice in a thatched cottage? time to rethink the whole scheme fella.

 

[yellowvanman]

It's not rodent 'proof' so to speak, however fire risk is minimised due to the metallic sheath protecting the conductors within by having fault current carrying capabilities. An RCD with a maximum operating current of 300mA would also aid with fire prevention.

Unlike T+E, a rodent chewing through an RCD protected BS 8436 cable would simply just trip the device.

Like I said, insurance companies instructions need to be followed and in the absence of such instruction, as a minimum I would be installing this. Again, as I said, a strong recommendation would be made for installing mineral.

I have used BS8436 successfully in a thatch before, hence my awareness of it not being rodent proof, but as you say a safer option than T&E and a cheaper option than pyro!

 

[D Skelton]

I have used BS8436 successfully in a thatch before, hence my awareness of it not being rodent proof, but as you say a safer option than T&E and a cheaper option than pyro!

Exactly.

When both options are presented to the customer then they can weigh up the pros and cons against cost implications themselves.

Remember, separate drivers for the LED spots!