Different types of plaster in ceilings

[Gavin John Hyde]

Been installing downlights today in a kitchen and dining room. nothing fancy electrically speaking but a pain in backside as one part is new the other old.
The new is bog standard plaster board. the old is lath and plaster. Using charcoal in the plaster so its like concrete. makes repairing the cable run holes dotted around fun!
The lath seems to be a hog wash of random bits of wood.
Got me thinking as its before my time, why did they use charcoal rather than lime. Was it just a cost or availability issue?
As it is certainly tougher to cut through. also makes a lot more visible mess as its a thicker grittier dust.

 

[pirate]

Never seen that stuff, but wondering if the dust might be toxic?
Was asked to install outside lights at a bungalow a couple of weeks back...1930's...yes, you guessed it...soffits were asbestos sheets...so, no worry about being fire rated then...
(cough, cough...splutter...)

 

[MDJ]

Gasp, another appalling thread

 

[pirate]

Gasp! another appalling avatar!

 

[Gavin John Hyde]

Have come across charcoal in the plaster before around these parts. I am using respirator, goggles, white suit etc etc..
Far better to be safe than sorry.

 

[ruston]

Have come across charcoal in the plaster before around these parts. I am using respirator, goggles, white suit etc etc..
Far better to be safe than sorry.

I have been the victim of a throat related disease .
I have worked in extremes of coal, quarry and farm dust as well as later in life all the domestic types. I am not saying this caused my illness, I am saying you have the right attitude.

 

[static zap]

Gasp, another appalling thread

whats with all this Gasping , reminding me of over inhaling Boy bands of yesteryear !

 

[Strima]

A lot of the block work round here installed in the 70's is a mixture of charcoal and flint.

Makes a right mess when chasing in but you get some nice sparks...

 

[telectrix]

i'm a nice spark.

 

[electric al]

They used to use whatever was convenient and available in order to give the plaster a mechanical bond and coal slack created a good aggregate. Around these parts we have something called black mortar which is very similar. I believe it was a bi-product from heating the steel furnaces and it is only really found in the old industrial areas of the city. Bloody horrible stuff !