How should I make this concrete block wall look better?

[Nesian]

Hi,

I have a single concrete block back wall which is in our toilet. It's from a 1970's house and of all things it was covered with carpet (the parts in the photos that look like mould are in fact the remnants of the blue carpet). I have since removed the carpet but the surface is very rough. Someone also mentioned that it might be worth getting it asbestos tested as the glue used might contain some? I was hoping for some advice on how to make this wall look good. Do I cover it with gib or mdf or something like that? If so, what would be the best way to do it?

Thanking you.

[JacobZ]

Hi @Nesian,

Thank you for your question and welcome to the Bunnings Workshop community, it's wonderful to have you with us.

You are correct that some carpet adhesives used before the 80s contained small amounts of asbestos. With this in mind, it is definitely a good idea to get it tested before continuing work.

Once you've had things tested, there are two ways I can see of tidying things up, rendering or relining the room.

Rendering would involve grinding back the wall to remove the rough surface before rendering over the top. This would be quite an involved process, but this would maintain the full space within the room and allow you to have a clean, painted look.

Relining the room would require you to batten out the walls with either timber or furring channel so you can attach plasterboard, fibre cement or other suitable wall-lining materials such as easyVJ. This will give you a flat, paintable surface, that is fairly easy to install on your own, which can be decorated to your liking.

There are pros and cons to both approaches and varying costs.

Rendering the walls would allow you to retain the full space of the room but would be quite involved and would likely require the assistance of a professional.

Whereas relining the room would be a simpler process, but it would come at the cost of lost space.

Some helpful articles that should help you get your head around the processes involved include:

• How To Render
• How To Apply a Top Coat To Render
• How To Plasterboard a Stud Wall
• How To Install Villaboard
• How To Stop Up Villaboard

Allow me to tag some of our helpful members to see if they have any other ideas @Dave-1, @ProjectPete, @Nailbag.

Let me know if you have any further questions.

Jacob

[Dave-1]

Afternoon @Nesian 

Carpet.... Oh the uses it has been put to... lol

I thought I had it bad with dark blue carpet in the bedrooms

How wide is your toilet area that you are renovating? I First thought of buffing the walls back with a drill attached wire brush. But then you would still want to smooth the surface afterwards.

I like the second option @JacobZ  has suggested and that is to line the room. Depending on space you could go for a minimun false wall and plaster it. Instead of a 70mm timber stud width plus 10mm plaster on either side you could turn the timber flat so its 35mm plus 10mm plaster either side. Way less effort them removing all that carpet and then rendering/smoothing.

Dave

[Nesian]

Thank you for that, it was very helpful.

I have submitted a sample of the carpet/adhesive to see if it does contain asbestos. That would probably determine how I approach it.

I probably should have mentioned this is a toilet/laundry so right beneath the window in the picture is the toilet which is attached to the concrete block wall and also plumed into a concrete floor so if I batten the wall out I'm going to have to move the toilet, which ideally I don't want to do as I will have to get the plumber to move it.

Is there any product (wall panel/lining)  that I can adhere directly to the block wall with adhesive of some type, that way I'll only lose the thickness of the wall covering and shouldn't have to move the toilet? That would also take care of incapsulating the asbestos if there is some present.

Thanks for your help.

[Nesian]

Yes, interior design from the 70's was a little different 😁

The toilet area is only 900 wide. I've just taken a sample of the carpet to get tested for asbestos. That would probably determine if I am able to wire brush the walls from here on in, as most of the adhesive is stuck to the brick and not the carpet.

Ideally I was hoping there was a wall panel or product that I could just adhere to the wall then that would encapsulate the asbestos (if present) and I wouldn't lose any space as the toilet is attached to the brick wall and plumbed into the concrete floor and I really don't want to move it if possible.

Thanks for your help.

[JacobZ]

Hi @Nesian,

It is possible to attach plasterboard to a block wall using the dot and daub method as shown here - Covering a masonry wall with Gyprock® plasterboard.

Unfortunately, plasterboard is the only product I am aware of that it is possible to do this with, so it narrows your options significantly.

If you wanted to go with this method, you would need to clean the wall thoroughly and then attach the plasterboard to the wall using Gyprock CSR 20kg Drywall Masonry Adhesive closely following the method that I have linked to above.

This will give you the flattest surface possible without giving up too much space.

Let me know what you think and if you have any further questions, please don't hesitate to ask.

Jacob

[Dave-1]

Afternoon @Nesian 

Yeah I get the tightness of space and also the issue of the toilet. @JacobZ mentions "furring channel" Which is an upside down U channel effectivly. I am not sure how shallow these can be. Other then that You could potentally go the route of 20mm timber vertically on the wall that you mount the plaster to. The only reason I am not saying mount the plaster to the wall is potentally it may have ripples and the wall would look wonky.

So down to 22mm for timber stud on wall, then 12 mm plaster. You loose 72mm all up across the width. For the toilet wall it may be easier gluing tha plaster/vera board direct to the wall as its only 900mm width wise.

Dave

[Herrenovacation]

Hi @Nesian 

I think the advice from @JacobZ & @Dave-1 is extremely helpful. 

I have a couple of brick or concrete walls that I'd like to cover also, lucky for me mine don't contain asbestos. 

I have decided in one wall I will render, and the other wall I have bought a timber veneer which is quite thin and I plan to glue it on. I am not sure how it will turn out but these are the options I have chosen based on look and not wanting to loose extra space. 

[Nesian]

Thanks Jacob,

I think attaching plasterboard to the concrete bock directly will be my first choice as long as the outcome of the lab report is positive for no asbestos as I will be able to clean the wall properly.

As another option, is there a product that I can skim the wall with?  I've watched loads of videos where in the UK skimming brick walls seems to be quite common.

Thanks,

Terry

[Nailbag]

Hi @Nesian as suggested by @JacobZ I would go with fixing directly plasterboard to the wall. This can be achieved without the need to batten the wall which will raise the issue of any possible asbestos. It's also a much simpler solution. See photos below of a similar project where I covered and old brick wall, when renovating a decades old downstairs bedroom.

Regards, Nailbag