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. 

[MitchellMc]

You would be right in suspecting that any retained water's hydrostatic pressure will be an issue @kristian. Rendering is probably the better solution than painting. It's more breathable, and moisture will have the ability to pass through it. However, it will get discoloured due to the moisture permeating the surface continuously. Paint isn't porous, and unless its holding power is greater than the water's pressure, it will peel off.

What's the issue with the wall at the moment? Do your friends just not like the look of the limestone blocks? Perhaps you could post some images to give our members a better idea of what they could suggest as possible coatings or solutions.

Mitchell

[kristian]

That’s great! Thanks.

Yeah, they’re not a fan of the yellow colouring. They’re redesigning the whole back yard at the moment and the pallette they like is whites, greys, wood with grass and plants. And the limestone doesn’t really go with the overall look they’re after.

I’ll get some photos and send them through. 

[kristian]

So here’s the wall. The garden bed runs almost the full length of the block. They’re replacing the paving and fence, painting and lining the patio, removing the shed, building a new open air fire pit/pizza oven area, and putting in new screening trees all through the garden bed. 

Thoughts?

 

[EricL · Accepted solution]

Hello @kristian

Thank you so much for the photo updates. It's great that you've received excellent advice from @MitchellMc. His assessment and recommendation are spot on. The issue is water coming from the other side of the wall. Now that I've read your friend's design preferences, I suggest the following options. Disguise the block wall by covering it with 137 x 23mm 5.4m Decking Alpine Ash / Ironwood Composite Ekodeck Designer. It is manufactured from over 80% reclaimed and recycled materials. It is resistant to termites, rot, decay, mould, and mildew. It does not require oiling, painting, or sealing. It comes in various colours so your friends can choose a colour that will go with their overall design preference. You can also use Merbau Decking Panels as a second material option.

My next recommendation is to cover it with 200 x 50mm 2.4m Treated Pine Sleeper H4. If they want a more chunky robust look this is the way to go. My final suggestion would be to disassemble the limestone blocks and create a new wall in their preferred material.

Let me tag our experienced members @JoeAzza and @TedBear for their recommendations.

If you need further assistance, please let us know.

Eric

[TedBear]

I agree 100% with @EricL .  Your friends need to focus on what they do want and not what they don't want (ie the limestone look).

The blocks offer strength in containing the garden, so removing them could be problematic. Painting the outer surface isn't wise, unless they seal the inner surface against water seepage first. Sealing the inner world be a good idea anyway, then add whatever veneer they wish (as EricL suggests) to achieve the look that they want to see. 

[kristian]

Thanks @MitchellMc, @EricL and @TedBear . Really appreciate all of your input!

I'm going to work up a few material mood boards for them, but looks like they'll either clad in a decking, or keep the limestone and change up the pallette to better match.

Thanks again!

[mariowilson]

Hi EricL

Do you reckon cladding would be an option to cover the limestone wall. I’m facing the same challenge at my place and looking for alternatives.

 

[MitchellMc]

Welcome to the Bunnings Workshop community @mariowilson. It's wonderful to have you join us, and many thanks for your question about cladding a limestone wall.

Cladding would certainly be an option, and your creativity is the only limitation. Bang for your buck-wise, you can't go past SpecRite 1800 x 902mm 84/44mm Fence Panel Merbau Slats. I've done the math, and they are comparable in price to the equivalent amount of decking timber. You could lay them lengthways and affix them to the wall. Alternatively, there's a whole range of screening to consider. It all really depends on the look you're going for. If you can let our helpful members what style might work, I trust they'll be full of advice and suggestions.

I'll be looking forward to hearing your thoughts and providing assistance with your project.

Mitchell

[alicia134]

Hi MitchellMc,

I also have a limestone ‘challenge’ that I would LOVE your input for! My house has a retaining wall that surrounds it and is made mostly of limestone. I would love to change it to an all white, smoother retaining wall. I will add photos of how it is currently and how I would like it to look. We’re ideally looking at the easiest/cheapest route to achieve this look or similar. Tossing up between cement sheeting or possibly render? Any input would be really appreciated ☺️