Hi all, how easy is it to install halogen downlighters in an old lathe &
plaster ceiling? The wiring is not a problem, I can sort that, just a few
things that cross my mind when I think about them.
1. once I cut a hole for them the wood lathes will be unsupported, what to
2. will the old ceiling be to thick for them to sit in, I think they fix
using metal spring clip things.I fitted some eyeball lights in our last
house but this had plaster board ceiling.
Any other points to watch out for?
Also what are the advantages or disadvantages in fitting mains powered as
opposed to low voltage ones. These are to be fitted in the kitchen.
I wouldn't rate your chances of cutting neat holes in a lathe and plaster
ceiling - although others claim to have done it ok. There was a thread on
this a little while ago - a Google search might find it.
With regard to mains vs LV, there are two camps - with those in each camp
tending to have strong views about it.
I personally prefer LV - because you get more visible light per unit of
energy input and the bulbs last longer. The downside is that you need
separate transformers - and the cables between the transformers and the
lamps need to be short and fat - because they carry much higher currents,
and you can't afford any appreciable voltage drop.
I've managed to do this in our ceiling, but its not straight forward mainly
because when cutting a hole with a jigsaw the wooden lathes vibrate causing
a larger hole than originally required, hence if you go down this route
start with a much smaller hole and work outwards slowly - hand tools may be
The job is very dusty and dirty - may be a good idea to send the wife out
for the day!!
The lights get very hot, hence you need enough (usually around 6 in)
clearance above them.
If you have no restrictions then go with mains ones as they dont require a
transformer (you have to hide a transformer away and they can fail after
time), the 12 volt type can also be a pain as the wires which connect the
lights between each other and the transformer are usually quite short which
can be quite restrictive. Having said this mains ones seen to be less
common, hence if you have a supplier great, if not then I managed the
eventually find some at our local argos superstore.
On Tue, 11 Nov 2003 14:47:53 -0000, Jonathan Pearson wrote:
Depending on the fitting, there might also be a problem fixing them too. If
the fitting has a clip expecting a plasterboard thickness of board, they
may not be able to cope with the thickness of the _lath_ and plaster (a
lathe is a big heavy thing for wood turning).
Something that might help the vibration problem is to plaster the top of
the ceiling around the cutting position before starting. Once set, this
should help hold it all together. Diluted PVA beforehand should help stick
the laths to the existing plaster too.
The other option is to cut out an area of ceiling and plasterboard it.
A hole saw in a variable speed drill worked for me, go at it as slowly
as possible. Not much vibration. If you get the right size hole saw, the
spring clips against the sides of the hole should hold the fitting up,
even if the plaster is too thick for the springs to open out.
We have both types in our new kitchen. I wish I'd gone for low-voltage ones
all round, as they have a much nicer light quality - sort of whiter, more
twinkly and modern looking. The mains voltage ones have a yellowish light,
rather like a tungsten bulb.
The reason for the 12v lamps being whiter is that they run at a higher
temperature. Because they carry a high current at low voltage, the filament
resistance is very low - so the filament is very short and fat compared with
a long and thin one in mains lamps. This, in turn, means that it is
physically much stronger and can run much hotter without failing. As any
schoolboy will tell you, the wavelength of light emitted is inversely
proportional to the temperature. Thus a higher temperature means that much
more of the radiation emitted is in the visible part of the spectrum rather
than down in the infra-red. This means more visible light (and less heat)
per watt of input power *and* the light emitted is whiter.
I recently fitted 30 12v eyeball downlighters in 2 new bedrooms and landing
in an attic conversion. It was lath and plaster which we ripped down to
create more ceiling space by moving the joists upwards. Then plaster boarded
and plastered. Hole saw to cut the holes.
Anyways, I went for 12v cos bulbs are cheaper and last longer and more
efficient- despite losses in the transformer. Situated the transformers
centrally in the room (where the original ceiling rose was) and ran radial
1.0mm 2core PVC to each light position from a 30a junction box at each
transformer. Min lenght was about 30cm and max about 3meters. All rooms have
dimmes which ensure a soft start. Despite the different cabling lengths all
lamps run at the same brightness, and look damn good!
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.