Can Hypertufa Really Be Used As A Top Coat
On A Vertical Wall?
I recevied an email from Donna asking me a simple question:
Can hypertufa be used to face a vertical wall?
My reply:
Hi Donna:
Thanks for asking me about this, and yes! You sure can use hypertufa to face a wall. This would certainly be a very doable hypertufa project that shouldn’t require too much “skill” – meaning this won’t require an advanced ‘tufa technique.
But, I need to know more in order to make sure about a few things … such as what is the wall made from? Brick, or concrete blocks? Or something else?? Are these walls outside in your garden, or inside a home or other structure?? (For now I will assume you mean a garden wall.)
Reason I ask is depending on the material of the wall’s surface, it might change the ingredients in the hypertufa recipe and/or application method. But if your wall is made from bricks or concrete blocks, from my research (I’ve never faced a wall with hypertufa) you will definitely want to wet down the wall’s surface; apply a liberal coating of a bonding agent to the surface; and use a hypertufa recipe that also has bonding agent added to it.
I can assure you that wetting down the wall surface is important, just like it is important when adding more hypertufa to an already cured area of ‘tufa. Wetting the surface is an important step.
This is bare-bones information, but without knowing all the particulars, this info should get you pointed in the right direction. Does this help you?
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Donna replied:
Thanks for the answer, Claudia. I’ll try to clarify my question a little but I like your answer.
We’re building a new house with an enclosed atrium. The walls haven’t actually been built yet but the contractor wants to face it with a concrete material like Hardyplank and then put some kind of stucco material over that to make it look like a rock cliff.
I want to allow plants to grow on the wall and thought a hypertufa “stucco” would work better than a plain concrete stucco. The contractor is concerned about the hypertufa being as durable as conventional concrete in this instance.
In your opinion would we use the hypertufa just like conventional concrete – over a expanded metal base used as the “support”?
Thanks again for your help. Donna
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I answered back:
Hi Donna:
The contractor is concerned about the hypertufa being as durable as conventional concrete in this instance. In your opinion would we use the hypertufa just like conventional concrete – over a expanded metal base used as the “support”?
Hypertufa being durable? Well, if it is mixed up in proper proportions and cured correctly, and if you’ve added reinforcing poly fibers (as one example) … heck! It is incredibly durable & most likely would last for goodness knows how many eons!
Plus, now that I understand that the hypertufa is going to be applied to the INTERIOR walls of your atrium (I’m jealous … an antrium! You lucky duck!!) the walls are protected from the “abuse” of the outside elements. That in itself should prove to help add to the longevity of the hypertufa.
If you’ve not yet looked at, or downloaded a copy of this very thorough stain and colorant chart that is on my website, please do so – it will be an immense help to you: Hypertufa & Concrete Stains Chart. You’ll see the link to open the chart about 1/2 way down the page.
About coloration: think carefully about the desired COLOR you want when you’re done. Peat moss is already “dark” by itself, and then you’ll have the grey portland cement. You really might want to use white portland with a colorant to lighten up the walls in your atrium. And be aware that the peat moss is going to be visible.
Also remember that the peat moss is meant to decompose over time, so that ultimately you replicate real Tufa rock. That’s the whole idea of people making things with a hypertufa recipe. But decomposition happens for objects like troughs or planters that are outside in a garden 24/7. In your situation, the hypertufa is not going to be affected by “normal” outdoor weather and seasonal conditions.
However, maybe over many years the peat moss will decompose in the planter pockets you’ll be fashioning – because when you water the plants, the water will cause the ‘tufa to slowly decompose … the peat moss in the walls might not. Unless you can hose them down?? Are you having a brick or pebble based floor with floor drains so that watering your plants and having to be “careful” with puddles isn’t an issue??
See where I’m going with this? I don’t see why a hypertufa recipe couldn’t be used. BUT!! I have NEVER done this myself; nor do I personally know anyone who has done this, so that I could pick their brain for you!! I say this to protect myself with the suggestions I’ve given you. Your common sense and more research into the best recipe; proper sub-surface for application; thickness of hypertufa to be applied … all that is up to you.
If I were you I’d experiment on practice boards with a few recipes using grey and white portland cement; maybe different colorants, etc. and let it cure so you really know what the final outcome will be color-wise! I’d hate to think you get the room done, and about a week later when the walls are getting dry, you say “Egad … I really don’t like what this looks like!!”
This is one of the more unusual hypertufa projects I’ve been asked about, but it should prove to be a wonderful addition to your home. I’d say “Go for it!”
Good luck!