installing lighting in a attic convertion and worried about transformer location

[Ben Ryan]

Hi everyone this is my first post. I have been using this site for a while and have learned a lot from reading other peoples posts.
I'm a recently qualified electrician and working for an experienced spark. we have just done the first fix on a attic conversion and the client has some very specific request about the lighting.
She wants spots running along each side of the slopping roof.

There is only a very small gap (4cm) and it is all insulated in a padded material with a foil like coating then 12mm plaster board and skimed. Not a suitable environment for any down lights that i have seen?

She has found some some cabinet surface mounted elv lights. I am not sure if they will give off enough light? Not sure of there spec yet either but i think it a 12w lamp. But this lead to the discussion about what to do with the transformers for these.

There is just enough room for the transformer to fit in. but it is not going be very accessible and I'm not sure how hot it will get in such a location? they don't last forever ether so do they need access right
Or do you go for single transformer somewhere else (not sure where yet) with a long run to the lights could be 5m or more to the furthest light.
The volt drop with this is going to be Bad i know so what do i do? make it into a ring? run it in large cable. or would a dc transformer work better? voltage drop is different in dc or have i got that one wrong?
Wow there is a lot of ? I did not want that to happen
any advice would be great

 

[RyanCheetham]

Those cabinet lights come pre wired with heat resistant cable with only about 1 meter of cable per fitting that all run back to a transformer with a 2core flat flex attached. Probably arent really what you are looking for. Although when you recess them tgey only take up about 20mm depth

 

[pjcomp]

Lights for under kitchen cabinets are designed to do a good job under kitchen cabinets, not to light a room. I think your customer needs to rethink her lighting and just accept that what she wants is probably not practicable.

PJ

 

[dagrat]

Hi everyone this is my first post. I have been using this site for a while and have learned a lot from reading other peoples posts.
I'm a recently qualified electrician and working for an experienced spark. we have just done the first fix on a attic conversion and the client has some very specific request about the lighting.
She wants spots running along each side of the slopping roof.

There is only a very small gap (4cm) and it is all insulated in a padded material with a foil like coating then 12mm plaster board and skimed. Not a suitable environment for any down lights that i have seen?

She has found some some cabinet surface mounted elv lights. I am not sure if they will give off enough light? Not sure of there spec yet either but i think it a 12w lamp. But this lead to the discussion about what to do with the transformers for these.

There is just enough room for the transformer to fit in. but it is not going be very accessible and I'm not sure how hot it will get in such a location? they don't last forever ether so do they need access right
Or do you go for single transformer somewhere else (not sure where yet) with a long run to the lights could be 5m or more to the furthest light.
The volt drop with this is going to be Bad i know so what do i do? make it into a ring? run it in large cable. or would a dc transformer work better? voltage drop is different in dc or have i got that one wrong?
Wow there is a lot of ? I did not want that to happen
any advice would be great

That padded material is almost certainly kingspan or cellotex insulation sheets. They can be cut out to make way for down lights but its the gap above them matters. Usually on loft conversions, sloping roofs, there is approx 25-50mm air space behind, so is not suitable for fitting or transformer. Looks like surface fittings are the way to go.

 

[Deleted member 26818]

Has all the loft space been converted, or is there some space behind a wall that could be used to hose a transformer?

 

[vjsmarwick]

I am guessing the foil padded stuff he is talking about is about 3mm thick and should not be cut out of the way normally fitted under floors a few years back can't remember the name off hand but once the membrane of this stuff is cut its pretty much useless in that section. But I could be wrong and often am lol