Replacing Lath and plaster ceiling

[David2749]

My daughter has just bought a 110 year old house, the main bed room ceiling is in a terrible state so decided to remove this. The ceiling wooden beams are in good condition but one or two seem loose.
What's your best advice, I did think of putting battens between the joists , will this be ok??

 

[JohnD]

Redo it in plasterboard and have it skimmed, or get the plasterer to do both.

What are the battens for?

 

[David2749]

I was going to get it boarded and plastered, but just thought as some of the joists move they might stop the joists moving.

 

[JohnD]

What are the dimensions of the joists?

Do you walk about in the loft or store things? Was the house built with slates (they are lighter than tiles, so Victorian roofs built more skimpily)

You can counter batten to increase stiffness. I used decking boards which are quite cheap and easy to find. I think I put them 600mm apart so an extra roll of insulation fits snugly.

While the ceiling is down it is easier to pass them up. Screw down tightly.

Check that the existing timbers are well fixed. Banging nails in may cause more looseness and cracking, so use big screws. Drill pilot holes to make it easier. If you use hex-headed or coach screws they are easier to tighten, especially in large sizes, but Pozi are cheaper and OK if access is easy. You can skew-fix from alternate sides.

 

[David2749]

I'm not sure how far the joists are apart, didnt measure them when I was there, but think about 600mm...
When you say you used decking boards, you mean right angles to the joists?
Some of the joist are really loose. I was going to use loft boarding from B&Q.

 

[JohnD]

I meant, are the timbers 2x4 or 2x6 or 1.5x3 inches. Also need the length of span between supporting walls.

B&Q loft boards are rubbish chipboard and poor value.

If you can get 18mm WBP ply in 2440x660mm and screw it down tightly to the counterbattens, that is far far better.
Wickes usually have it.

Yes, counterbattens at right angles to the joists, and screwed down tight.

I doubt you could lift 2440x1220 boards into the loft, but the bigger the better as it has no joints to weaken it. The yard might cut them for you for better value than small boards.

Have a look for woodworm and rot as well. Worm usually round the loft hatch as they like the warmth.

 

[David2749]

I think the joists are really small, probably 4×2 . I think the idea of ply sounds a better idea.
Thanks for advice

 

[mrrusty]

If the roof has large purlins to support the rafters, the ceiling joists don't have much work to do except hold the ceiling up, so may be quite small with hangers to the purlins. (However, ceiling joists may also be the horizontal brace that stops the roof spreading - it depends how the roof is constructed). If you intend to use the loft for storage then cross "battening" will certainly add strength. The joists are also unlikely to be in quite the right place for boarding (because you need to support every edge to avoid cracking). You can trim board to odd sizes, but better to add additional timbers and noggins so that the board edges are neatly secured. When they constructed lath ceilings, the spacing of joists didn't matter, so they may be quite variably spaced.

They may well be loose because old fixings have perished, particularly where the joist end sits on a wall plate in the eaves. Easy to rectify. Don't bother drilling pilot holes - use good sized and quality screws (e.g. reisser cutters) and drive them in with an impact driver - as said above on the skew is fine. As said, if joining large timbers together side by side, coach screws with hex heads are useful. Think whether the screw is doing a structural job or just keeping something in location.

Putting in the timbers and screwing the plasterboard in place is well within DIY capability - use plasterboard screws not regular countersunk - take time to do it neatly. Plasterboard is also available in 900x1800 which is easier to handle than 1200x2400 (note PB is usually this size and not the imperial 8x4 equivalent 1220 x 2440) Your plasterer can then come in and skim it all up. Job done.

 

[mrrusty]

And, BTW, if you have ceilings in bad condition but with decorative cornices you want to retain, then come back here again for more tips.

 

[David2749]

Thank you for all your advice, my daughter has since sunday had a builder come in to quote for an extension, and has seen the ceiling or lack of one in the bedroom, and told her the ceiling timbers are too narrow to plaster board on, only 40mm.
I was worried this might be the case .

 

[mrrusty]

and told her the ceiling timbers are too narrow to plaster board on, only 40mm.

And the builder is talking b*****x. Either that or all the plasterboard ceilings in my recent 1902 refurb are an impossibility. What he probably means, is what I said above - they won't be nicely spaced for the standard plasterboard sizes. What I do is measure from one joist and add an extra joist to pick up the edge/joint. In this way you might have to add a few extra joists, but 40mm is enough to get a fixing in. when you buy "3 x2" or "4 x 2" timber it will probably be actually only 45mm wide anyway...

 

[David2749]

Just before you all die with boredom from my questions I've decided to plaster board the ceiling myself.
Do I get tapered or square edges boards??

 

[mrrusty]

square edged. Do use plasterboard screws, not regular countersink, and note they are usually philips head and not posi. https://www.screwfix.com/p/easydriv...ck/12984#product_additional_details_container