A Budding Concrete Sculptor Asks Some Questions
I received two emails from Eugen who asked (please note English is not his primary language 
it isn’t because he is such a bad typist!):
I have a question – where from peat moss , and if that could be replaced by another material wayting for your suggestions, thank you in advance, yours, eugen
and …
I also find your site very interesting I’m a doctor gp pasioned by sculpture, I intent to build( create) few large statues in my garden with concrete, but still didn’t found some clear overview about waterproof methods. If you have any valid ideas about this, please answer me. Thank you again, eugen
My reply:
Hello Eugen:
Thank you very much for contacting me and as I received two emails from you, I will be happy to try and answer all questions here. Also, please appreciate I am doing my best to understand your questions, as your English is obviously not your native language (I mean no disrespect to you by saying this). It is just that I want to do my best to help you.
You ask: “where from peat moss … and could it be replaced ….”
#1) Alright, if you are asking me where you can FIND or PURCHASE peat moss, here in the USA it is very easily purchased in garden supply stores. It comes in a compressed square-ish shaped “bale”, and is normally used as a soil amendment for garden beds. Since I do not know what country you live in, I cannot be more helpful at this time. The type of peat moss used for hypertufa recipes is sphagnum peat moss.
#2) “can it be replaced” …. NO. Hypertufa is not hypertufa unless it has peat moss as an ingredient. Any other type of cement based recipe (as hypertufa is), will be a concrete recipe … not a hypertufa recipe. But, that being said, I have a recipe on my site that utilizes coir in place of peat moss. Please refer to: Hypertufa Recipe Using Coir
#3) Or you can use plain soil as a replacement (note there is no perlite in this recipe): Garden Stepping Stones Recipe
Next, you ask about waterproofing methods for concrete statues. Why? As I am sure you are aware, if your recipe is prepared correctly, and you cure your sculpture properly, it should last a life time. However, if you wish to waterproof it as you are wanting part of your sculpture to be a water basin, as example, or maybe you want your sculpture to attain a glossy appearance, then here in the USA I would go to a store that sells cement supplies, and purchase a concrete sealant. Just make sure what you purchase says “Waterproof” as opposed to “Water Resistant”. You should apply at least 2 coats, 3 or more is better.
Or, here is a technique I have pulled from my files for you: For items such as birdbaths and such that will be constantly holding water, instead of using expensive and often questionable sealers…finish just the “bowl” portion of the item with modified cement. Plain old concrete does a pretty good job of holding water, but you can easily take it to the next level by mixing up batch of pure, neat Portland (no sand) and polymer admix to coat that area.
It can be plain gray, pure white (white Portland) or colored using integral color. You can even get a marbleized effect using multiple colors. Poly-modified cement is extremely dense and about as watertight as you can get. It can be visually interesting too since the surface can be as smooth as glass (with a little sanding & polishing) or textured to your taste. It bonds very well to lightly textured concrete. As an added measure, apply a light coat of Carnauba wax and buff it just to finish it off.
So … are these answers of help to you? Please do not hesitate to contact me for further clarification or help if needed.
Also, if you have not reviewed the stain and colorant information, please do. It is the best available on the internet, and though the brands mentioned may not be available in your country (or are you living here in the USA??), the application methods, etc. is valuable information: Colorant Charts For Hypertufa & Concrete
Good luck! I wish you much success with your sculpture project
