behind cornices - mortar question

[DIYFan]

hello everyone, 

Needing some advice on this job. For context the top floor apartment leaked and had for years so the ceiling came down (it was part skim coat, bog, glue and who knows with a lot of mould chucked in for good measure). They say the flat roof is now fixed (I have doubts) Plans now to put channels and gyprock to allow greater airflow and if there is issues then I can replace the ceiling far easier than this time around. 

question. Cornices are down and mortar behind is cracked, holes, uneven. Cornices won’t go back up. But I would like to have fixed as half will be on show as ceiling won’t be that far down.

I’ve heard using gutter wire, chicken wire, newspaper, glue.. all sorts of random stuff to fill the holes and fix. I have looked at using rapid repair mix but want to make sure it sticks and if I’m missing something. Can someone give me a knowledgeable recommendation please.  There is a slight ledge that I’ll be clearing off and just need about 30mm flush fixed so the ceiling doesn’t show this. (It’s about 60mm in total from ceiling down)

thank you in advance 

 

 

 

 

[MitchellMc]

Welcome to the Bunnings Workshop community @DIYFan. It's fantastic to have you join us, and many thanks for your question about repairing a wall.

Are you not installing cornices after lowering the ceiling? I would have thought that the lowered ceiling and then new cornices would conceal any of the gaps. You can certainly chip out any loose material, remove that ledge and fill with Rapid Set Mortar. Once set, you can go over that with Hardwall Plaster.

Since you're working on an older home, be cautious of potential asbestos-containing materials. Asbestos was commonly used in things like insulation, flooring, and roofing. Disturbing these materials can release dangerous fibres, so it's important to get a professional inspection and use licensed contractors for removal if asbestos is found. Always prioritise safety when dealing with unknown building materials.

Please let me know if you have any questions.

Mitchell
 

[DIYFan]

Thank you Mitchell, 

there isn’t going to be cornice installed given the possibility the roof will again fail and water in. The slab is wet and needs to dry so happy to leave a slight shadow gap to allow for airflow. If the gyprock ceiling is installed on a slight channel then it would be sure easier to remove if water damaged in the future (this has been hell removing this time around). 

the walls are mortar so would I need to go over with plaster? Would be varied texture otherwise but it is a small area so happy whether works. 

as for the asbestos, the ceiling was tested and no positive result. The floors boards were installed in 2011. But the tile glue which was underneath as the previous floor contractor didn’t fix the floor dates back to 70’s was ground off with. Concrete cup and we were all masked up. It’s on a concrete slab. Fingers crossed it isn’t anywhere else in that. 

Kris 

I

[MitchellMc]

Hi @DIYFan,

Are the walls mortar or brick? Typically, on older brick dwellings, they went over them with hard-set plaster, though I suppose the bricks could have been rendered in mortar. Normally, they would use plaster as it's easier to sand back to a smooth surface. If the walls are mortar, then you could just use the rapid-set mortar.

Mitchell