chase concrete ceiling for 1mm csa lighting?

[mgx]

I suspect the answer is no, but I'll give it a try.

I'm redoing my flat, constructed circa. 1972, ceiling is concrete sitting on pylons, I'm on the lower ground floor of five floors.

The bugger is that I want to put a pendant light in the dining room, and put a bulkhead (with downlights + back led lighting) in the kitchen, but since the ceiling is concrete (and I have no false ceiling, nor desire to put one in - already ripped some out!), the only options would be to run the cables (in each case, ~1-2m distance from the wall, and cable is 1mm csa) in clipped on conduit (looking yuck) or shallow chase the ceiling. Prefer the latter. However, (a) is it actually structually safe to chase lightly for this short distance, and if so, then (b) how to do you do it practically (given the concrete is tough, and without mortal danger (I don't, nor probably does any one else, fancy standing on a platform holding a diamond cutter upwards!).

 

[Steve]

why dont you want a false ceiling? easy to do. just put up battens across the ceiling and board it. needn't be too low, maybe only an inch lower! nobody will ever know!

 

[mgx]

We are on the lower ground floor, ceiling height is only 2.4m so it is non-starter to lose any height with a false ceiling. All our lighting is wall based otherwise. The dining and kitchen areas are both open plan in one large 35sqm L-shaped room, and we want some overhead light for these two if we can.

But for the kitchen bulkhead, I could live with some surface conduit if we made the bulkhead large enough so the conduit is only visible for about 30cm. For the dining area, if I had to use surface conduit, I'd just not do it.

 

[Steve]

"only 2.4m"

be glad you have that! a lot of homes have been built with 2.2m or 2.1m in the last few years (3 storey homes to save height).

You have a bit to loose there, I really wouldn't panic about looseing a couple of inches.

I wouldnt go chasing a concrete ceiling, as its normally structural. Instead of bulkheads just go ahead and cover the whole ceiling.

 

[mgx]

Heh! Your advice much appreciated. The ceiling is certainly structural - I thought a shallow chase for a short distance might be safe though. I guess we have lived in places with higher ceilings in the past, and since the lower ground floor is a bit darker (longish layout, no side windows, but large patio doors at each end), we're sensitive to ceiling height. Also, the kitchen bulkhead is a design feature, as it gives a frame to the kitchen (the kitchen is low profile - no wall units for example). Also, we're doing full height doors through the whole flat - so if we put a false ceiling in one room just for a bulkhead and a light, we'd have to do it through the whole flat which isn't worth the effort (we're even removing the false ceilings from the bathrooms, no need!)

 

[Chri5]

Stick a mirror on the ceiling and point a floor lamp at it

I wouldn't touch the ceiling slab it could lead to all sorts of issues above you.

What about a bit of 1.0mm TE in white fixed with a glue gun to avoid fixing bumps and astetic issues with clips ?

MICC ?

Or as mentioned 18mm baton, 9mm board + skim = <30mm drop in ceiling height.

I'd also ask that if you think the ceiling height is very low, why have a ceiling fitting that is likely to get knocked via a tall person and from a 'look' prespective make the ceiling look lower than it is !

 

[bernardgreen]

(a) is it actually structually safe to chase lightly for this short distance,

Almost certainly NOT SAFE. The effect is the same as the glass cutter's score mark. It creates a weak point at which the stressed concrete can start to break. One bouncy neighbour upstairs and the weak point starts the big crack.

And if you expose any of the re-inforcing bars then atmospheric corrosion starts, slow process but one that very much weakens the structure over the years.

 

[CortinaV8]

As its his birthday today, why not try to use Teslas theorys on wireless electricity, could solve your problems.

Lets face it though, an inch is going to make naff all difference on headroom. Unless you are like 8 foot.

 

[ColJack]

you can get away with a 10mm drop in ceiling height..
put the cable up with capping and then get the ceiling skimmed.. only need about 10mm.

 

[Adam_151]

Thats just asking for someone to stick a drawing pin into it!

 

[17thman]

if you go the batten route with boarding careful how you fix them. dont want to drill up through their nice new underfloor heating elements. fix the cable with clips, then dot and dab new plasterboard over, then skim. you lose 15mill, enjoy

 

[mgx]

Thanks for all the replies - but I am not going to put a false ceiling through a 35sqm room or 100sqm flat just for two small issues like this, too much cost and hassle (even if we were aesthetically okay with it). It looks like for the kitchen bulkhead, I will just need to fashion a cable (maybe swa) or some discrete low profile trunking for a 30 cm run between the wall and the bulkhead - I can do this close to the back corner so it will not be very obvious. For the dining room light, I am not sure - either a cable or no overhead light at all - I'll see what the wife thinks here . Many thanks once again.

 

[ColJack]

Thats just asking for someone to stick a drawing pin into it!

I'd like to see you push a drawing pin through steel capping..

it might not protect against a nail hammered in, but unless you're built like a pro wrestler then you'll be hard pressed to push a tack in with your thumb..

 

[ColJack]

you could put wire mounted spots in the dining room? te wires run from wall to wall and you clip the lights on..

 

[Steve]

depending on the decor in the room, shiny metal conduit can look very good.