What is my ceiling made of and what should I do to it?

abankerbutnotafatcat

Hi everyone,

following a leak part of our ceiling fell down. We have been advised to pull the whole thing down (which will make some scheduled electricial work easier) and then get it plasterboarded over.

Primarily, we want to know what the ceiling is made of just to make sure it isn't asbestos. We were expecting lath and plaster (1901 house) but it doesn't look like the other ceilings made of this we've got.

Whilst we're asking, if anyone has any advice for the best way to make it good: remove both existing plasterboard layer and underlayer, just remove and replace the existing plasterboard or just repair the plasterboard bit that's gone?

The underlayer does appear to be rotten in places due to the leak but the rest of the ceiling appears sound other than 1 hairline crack in the middle.

http://www.flickr.com/photos/78523497@N08/7189675006/

renovation_man

I can't be positive just with the picture but it could be cement fibre board, there are various types of cement particle board.

From experience I have found that sometimes the skim may seperate from the fibre board due to age or shrinkage, if it will scrape off try and locate the existing board fixings to the joist and board over without removing the existing ceiling. Alternatively you could try and measure them out and try and find them with a drill, ceiling joists are normally at 400mm centres but this depends on the span, but I would not remove the existing ceiling.

Beware of any pipework though

Ash_McCloud

Cheese. ....

SailorSam

The joists want be at metric centres on a 1901 house, they'll be feet and inches.
It doesn't look a very big section, i think if it can't be skimmed i'd cut out just that bit once you've found the joists. Don't worry about the other hairline crack it's probably just where two pieces of plasterboard meet. Put a finger full of filler in it before you decorate.

renovation_man

About 16'' then?

keystone

abankerbutnotafatcat wrote: »

We have been advised to pull the whole thing down (which will make some scheduled electricial work easier) and then get it plasterboarded over.

Presumably by the sparks as it will make his job an awful lot easier I'm guessing at no reduction in cost to you.

Primarily, we want to know what the ceiling is made of just to make sure it isn't asbestos. We were expecting lath and plaster (1901 house) but it doesn't look like the other ceilings made of this we've got

Its already been boarded once and skimmed by the look of it but can't think why you would think it could be asbestos tbh.. If you replace it the coving comes down too don't forget.

Whilst we're asking, if anyone has any advice for the best way to make it good: remove both existing plasterboard layer and underlayer, just remove and replace the existing plasterboard or just repair the plasterboard bit that's gone?

From the pic it looks like the skim has gone rather than a layer of plasterboard. Could you elaborate? If I'm right I'd just have the area thats dropped off reskimmed but if you are unsure get a plasterer in to look at it.

Cheers

keystone

SailorSam wrote: »

The joists want be at metric centres on a 1901 house, they'll be feet and inches.

From a measurement perspective does it not depend on whether you use the imperial or metric side of your tape?

Cheers

abankerbutnotafatcat

Hi, firstly, thank you for all your useful comments - it's horrible to feel out of your depth in the face of conflicting advice so your help is really appreciated.

Yes, it was the electrician who advised that we take the whole ceiling down and it did make us wonder whether this was driven by the convenience factor.

The worry about asbestos came from me reading my 'Victorian Homes manual' in an effort to better aquaint myself with the issues. It showed lath and plaster and it looked as our other ceilings had but this one looks quite different. It then mentioned that some asbestos ceilings were put up in houses refurbished in the '60s/'70s and we didn't want to risk it.

Yes, losing the plaster coving was a concern. We would rather keep it as it matches the rest of the house and I wouldn't bother replacing it with polystyrene.

If I'm reading your various replies correctly you are saying that the two layers that are visible were, infact, originally joined but have separated over time. Is the advice to try to skim the missing part first (I don't think this will be possible as the rest has come away from the underlayer) and if not to remove the plaster surface only and re-skim over this?

If any of the undersurface has previously been wet will it be a sound surface to skim over? The bit you can see is presumably the bit that got wettest.

If it is skimmed then presumably it won't need plasterboard and the issue re joists won't matter or have I misunderstood?

It isn't that big, perhaps 60cm x 60cm in a 3m x 3.7m room. I think the plaster over layer will easily come away from the underlayer by the looks of it.

thanks once again.

renovation_man

As I said in my post I have experienced the delamination on several projects, if you just try and make good and skim the patch it will flash when decorated.

If delamination has occurred once it may happen again so I wouldn't skim over unless your looking for a cheap way out, this is caused by poor bonding methods. I can only say what I would do on my own property and never do half a job for a client unless they specify it.

keystone

Four very good reasons why he needs to get a plasterer in to advise then.

Cheers

abankerbutnotafatcat

renovation_man wrote: »

As I said in my post I have experienced the delamination on several projects, if you just try and make good and skim the patch it will flash when decorated.

If delamination has occurred once it may happen again so I wouldn't skim over unless your looking for a cheap way out, this is caused by poor bonding methods. I can only say what I would do on my own property and never do half a job for a client unless they specify it.

Does 'flash' mean 'show/fail'? i.e. not a good thing.

Some of the other advice did seem to be to skim but perhaps i misunderstood or is it ok to skim if I remove the 'laminate' layer because I note you say in your other post not to remove the existing ceiling. Sorry if I'm being thick but I am abankerbutnotaplasterer and that brings me on to Keystone - I am also a she!!

Our electrician's quote has 'making good including replastering as necessary' so he will be working with a plasterer. This may be slightly more work than he envisaged so we will pay him a more if required to get a decent job.

Thanks again.:)