DIY Prepare large gap before tiling - Tile Advice

[McGern]

Hi,

I've got a large gap behind the radiator in the bathroom where the tiles and plasterboard were removed to change the pipe layout. I am wanting to now fix the gap and retilw the area, but am not sure of how to fix the hole correctly without causing a lot of extra work. Hopefully the picture attached illustrates the issue. I mostly have access, and there is small gap between the plasterboard and the brickwork, but not a lot. So looking for a little advice please.

Thanks

 

[angrypirate]

I would remove the tiles on the right of the picture to see if theres masonry like the left. Carefully glue some 6mm tile backer board in the hole then patch.

It is awkward and fiddly but do-able.

 

[Dave]

Fill the big hole ( missing brick ) with expanding foam and the rest just dot and dab with plasterboard.

 

[Taylormade]

Is it a ground floor bathroom? Zooming in looks like you have dpm there. If so you don’t want to compromise the dpc.

 

[McGern]

Hi, thanks for the replies.

Some further info that might assist

• It's a downstairs bathroom that was a conversion from the "cupboard under the stairs" as part of an extension we had done recently to a typical Glasgow turn-of-last-century mid terrace, where the floor was lowered and the back pushed into what was the kitchen.
• It was lowered below the existing floor level
  • the bricks on the left are part of the foundation and, as @Taylormade pointed out, it looks there is a slate dpc (had to look that up). Not intending on touching any of that if possible.
  • the right hand side has no bricks because it is part of a void that open into underneath the house. It may have been of the access or airways under the house. There are no bricks above or to the right within reach
• I think that the plasterboard might be attached to studs above the old floor line, not sure what it is attached to below, but there is a fat finger gap between the plasterboard and the bricks on the left, and nothing behind the plasterboard on the right
• The gap covers 4 whole tiles, and about 2 and a half tops of tiles at the new floor level
• On the floor level, there is wood, which I'm assuming was added to fasten the plasterboard (?).
• The piping shown would be snug against the brick and plasterboard (or whatever end up filling the gap) once it is fit, and I will need to hold it back with something so it doesn't push back while the gap is being sealed.

Attached is a couple more pictures:- perhaps a better view of the whole thing, and closeups of the left and right hand sides.

I am thinking I will need the backing board idea to have something to fix the plasterboard to.

Thanks again.

 

[Kevbos]

Hi, thanks for the replies.

Some further info that might assist

• It's a downstairs bathroom that was a conversion from the "cupboard under the stairs" as part of an extension we had done recently to a typical Glasgow turn-of-last-century mid terrace, where the floor was lowered and the back pushed into what was the kitchen.
• It was lowered below the existing floor level
  • the bricks on the left are part of the foundation and, as @Taylormade pointed out, it looks there is a slate dpc (had to look that up). Not intending on touching any of that if possible.
  • the right hand side has no bricks because it is part of a void that open into underneath the house. It may have been of the access or airways under the house. There are no bricks above or to the right within reach
• I think that the plasterboard might be attached to studs above the old floor line, not sure what it is attached to below, but there is a fat finger gap between the plasterboard and the bricks on the left, and nothing behind the plasterboard on the right
• The gap covers 4 whole tiles, and about 2 and a half tops of tiles at the new floor level
• On the floor level, there is wood, which I'm assuming was added to fasten the plasterboard (?).
• The piping shown would be snug against the brick and plasterboard (or whatever end up filling the gap) once it is fit, and I will need to hold it back with something so it doesn't push back while the gap is being sealed.

Attached is a couple more pictures:- perhaps a better view of the whole thing, and closeups of the left and right hand sides.

I am thinking I will need the backing board idea to have something to fix the plasterboard to.

Thanks again.

To me it would be hard for anyone to give good advice ! Because if that gap was an old air flow or an air brick has been removed at some point then you need to leave that airflow !the area looks very damp or it has been at something by staining of plasterboard and colour of debris ! Maybe you should find a decorative air brick or grate and place that in there and tile upto it !!