How to prepare wall after removing old splashback?

[crisis]

I have pulled out my kitchen and just removed all of the splashback tiles. My question is I’m not sure what I do now to the wall behind the oven installing new cabinets and splashback. I know I need to remove the mortar (grey stuff) but where do I go back to with the rest? It’s a  mix of plaster, mortar and I’m not sure what… Advice..? Do I need to pare back to the brick and then put new plasterboard…? Note that the oven and upper cupboards have now been removed and there is plaster behind them. Thanks so much 

[MitchellMc]

Hi @crisis,

As long as there aren’t any significant deviations in the wall surface, I would suggest lining it with either plasterboard or cement sheeting. This will provide you with a smooth, flat surface to continue your renovation. However, if you’re aiming for a more original finish that aligns with the wall next to it, you may need to remove the existing adhesive and apply render or hard plaster to the wall for a level finish. 

Lining the wall with sheeting will give you the most level results, and it can be adhered to and fixed directly over the bricks.

Please let me know if you have any questions.

Mitchell

[crisis]

Thanks! This is exactly what I was hoping to hear 😊 So can I just sand the wall back to the level of the brick and install the plasterboard? Is plasterboard forgiving? Does it need to be perfectly level before i install? 

[crisis]

Or are you suggesting I could install plasterboard straight over the top of current surface provided there are no major deviations? 
thanks again

[MitchellMc]

Yes, provided there are plenty of contact points for your adhesive @crisis. It just needs to be relatively smooth. You'll find the instructions on page 29 of the plasterboard installation guide. It is recommended that timber furring strips be installed onto the wall first and then the board over them be installed.

Mitchell

[crisis]

Thanks so much. I wasn’t aware of this technique of using furring strips to kind of create studs on a brick wall to attach plasterboard and allow air circulation behind the board. I can see what I need to do now. I will post a photo when I’m done. 

[crisis]

I am yet to do this job but am now wondering if I need to do anything at all? I am reluctant to add furring strips because it will impact my kitchen install. If the new kitchen I will be installing will cover most of the wall,  is there any reason why I couldn’t install cabinetry incl an oven and cook top and a splashback directly to the wall as is? Or would I be a bit dumb to do that without plaster because the surface won’t be even? Cheers

 

[JacobZ]

Hi @crisis,

If the surface is relatively flat, the existing plaster is well adhered, and it will all get covered, then it is likely not necessary.

As any wall-mounted cabinets will cover the top half and the cabinets will cover the bottom half of the wall, the main area I'd have some concerns about is the splashback, as it will need to stick to the surface.

If you are confident that the existing plaster is well adhered, then you should be fine to proceed, but if it is not, it is likely worth scraping off the old plaster and applying a new coat of render or Hardwall Plaster to smooth the surface and give a better surface for the splashback to adhere to.

Let me know what you think.

Jacob

[crisis]

I think that makes sense but wasn’t sure if I was missing something. Do I need to worry about having water resistant plaster behind oven and cooktop to prevent issues of condensation on the wall? I’m wary of moisture as this wall had high moisture due to a lack of waterproofing in shower on other side of wall. When I removed the old cabinets they were rotting. 

[EricL]

Hello @crisis 

If the shower has been properly repaired and a water proofing membrane has been installed, no moisture or water should come through that wall. If water was to come through, any paint or sealer placed over the render would peel off due to hydrostatic pressure. But as I mentioned if the waterproofing membrane was put in place properly, there should be no water coming through.

Eric