Can you paint reconstituted limestone blocks?

[kristian]

Hi there, I have some friends that asked me whether you they would be able to render a long reconstituted limestone block retaining wall/garden bed. I said rendering it would probably not be a good idea but they miiight be able to paint it.

Anybody have any expert advice?

My main thought is that the garden bed isn’t sealed, and just being outdoors with limestone being so porous that moisture is going to make it’s way behind the paint and it will start coming off pretty quickly. 

[Jason]

No problems @alicia134. I'm sure our resident Bunnings D.I.Y. experts @MitchellMc or @EricL will be able to assist you. 

Let me extend a very warm welcome to the Bunnings Workshop community. We're really pleased to have you join us and look forward to seeing how you can transform your retaining wall fence, and tackle other projects around the house and garden.

Jason

[MitchellMc]

Hi @alicia134,

The easiest method will most likely be cladding the wall with Cemintel 7.5mm 1200 x 2440 External Cladding Sheet. 

Is this wall retaining soil that is pushed up against the rear of it, or is the wall wholly above ground? If it is retaining soil, you could see discolouration from soil leachates bleeding through your render. Rendering the wall will quite possibly be cheaper than using sheeting. However, if it's just the section you have pictured, I'd suggest going with the sheeting, as it will give a far more consistent finish and not have discolouration issues.

Please let me know if you have any questions.

Mitchell

[kris5]

Hello

Just joining this conversation as I have a slightly similar question.  Could you potentially stain a limestone block wall with something like a Crommelin Liquid Stone in basalt colour.  Or do you think it would it be the same result due to the water issue?

Regards 

Kris 

 

[KatieC]

Hi @kris5,

First, let me extend a warm welcome to the Bunnings Workshop community! It is awesome you have decided to join and ask us about staining your limestone wall. Our resident DIY expert @MitchellMc will be back online tomorrow to assist with your question but in the meantime let me tag members @TedBear and @Adam_W to see if they have any advice. 

We would love to see your project progress so please update us with photos. 

Katie

[Adam_W]

Hey @kristian just to wade-in late to this chat...

Agree 100% about painting basically any masonry retaining wall. If it wasn't properly water-sealed on the rear when built then it will wick moisture through to the face which will lift paint off. It can also do the same to render however a rendering tradie may have solutions for that with various ad-mixes they can put into their mud.
Battening the wall and adding a new face and then capping the wall can totally transform it. To give you an idea of how effective this can be in this older video of mine I do just that with a timber wall to make it look like a masonry.

[MitchellMc]

Hi @kris5, 

Crommelins LiquidStone is more similar to paint than a stain. Once again, it's a water-impermeable layer, so you'd run the risk of it being pushed off the surface.

Mitchell

[TedBear]

Hi @kris5,

@MitchellMc's reply about water pushing paint off a surface describes my own situation with the flat (but not flat enough) concrete verandah roof on my house. I noticed after we bought it that the paint underneath was stained, so assuming it was a small issue and without checking the actual problem (foolishly), I sealed and repainted it. Then, come winter, I noticed large drooping sections in the paint. Cutting them with the corner of a scraper resulted in me getting covered in water, which had come straight through the concrete and pooled in the paint layer. 

When I then looked above, there was a big pool of water up there (incorrectly sloped slab).  I coated the top in bituminous paint and waited another winter to check that there is no water bleed through, so I can now repaint the lower surface.

If you can get at the garden side of that wall and seal it, you should then be OK to paint over the stained outer side of the wall, but don't do it until it's sealed... or create a second outer surface as suggested.