Treehouse Pizza

[SableSprings]

Looks great Randy! Hopefully your predicted rainfall won't hit your place and you can feel more comfortable going slow with the curing. That pizza party will be memorable for everyone... Fabulous job! (FYI: the extra countertop surfaces will be well appreciated when you start using this beauty)

[RandyJ]

Well I lucked out and it didn't rain again today. So I am now completely done with the pearllite render. I am very glad to have finished this step. I also feel like it went on easier yesterday than today. Not sure what the difference is? Oh well I am just glad to be done with this step. The kit came with a Styrofoam float that was curved to fit the dome. I could not get that to work for the life of me. So I just used my pool trowel and it came out fairly decent I think. I guess I almost don't want it to be a perfect sphere as the rest is a bit rustic and that is how I envisioned the thing in the first place. Not sure what I was doing wrong today but the render just was not staying in place as well as yesterday. It was rougher texture yesterday so that probably helped. Oh well it is done now and covered as we are supposed to get like 4" of rain in the next few days again. Now that I have this step done I may still have a chance to make pizza on July 2 for my sons birthday. I guess time will tell and we will see just how many days it rains.

Randy

[RandyJ]

Ok I went out yesterday and got a new mixing tub and some more Portland and sand. It has been raining here a lot. I believe we have gotten like 4 or 5" of rain in the last few days. It is also supposed to rain for most of the next week. This is making it very hard for me to try to finish this up. We were supposed to get more severe storms this evening. It was not to bad when I got home so I decided I was going to go for it and do another coat of pearllite render. I managed to get this all done. And I think I have finally wore off all the rough skin I had built up on my hands from work. I was doing the render with bare hands as I did last time and finally I was a bit sore when done. Not bad just noticed that I probably better wear gloves next time. I really hope I can get the last coat on here soon so I can maybe make my sons birthday for first pizza. I didn't think I would have any problems with that but weeks of heavy rain are saying otherwise.

Randy

[david s]

The silicone coated stuff is not available to me. I would try it if it was. The water requirement for the non coated stuf is, depending on the grade, around 4L for every 10 L of perlite or vermiculite used in the mix. So the coated stuff should presumably dry faster with less free water to purge. Drying is very dependant on weather conditions. A combination of temperature, airflow and moisture in the form of sun, wind and humidity are the controlling factors, so it's hard to say how long it will take. In one way the non coated stuff has an advantage in that, containing so much free water, it doesn’t require damp curing to enhance its strength. However that will not increase the strength of the layer much when a weak aggregate is part of the mix. (See table).Try to avoid mechanical mixing. Doan already weaking it by hand has the advantages of being able to inspect it closely while mixing as well as feeling the consistency and texture of the mix. in any case as previously stated you should follow the manufacturers instructions or you may void your warranty .To explain my reasoning see table and attachment (for 5:1 underfloor vermicrete, but strength and insulation value also apply for dome insulation).
Another useful trick is to use an inexpensive garden moisture meter to test the moisture deep in the vermicrete layer. It may look dry on the surface but deep in it will probably still be quite moist.







Vermicrete insulating slab copy.doc.zip

[Giovanni Rossi]

RandyJ I picked up one of those cheap plastic mixing tubs (~$10) at HD for to mix small amount of concrete. It was just the ticket for the Perlite render. david s is on target about the hydration, but the Pertlite in the kit is treated with silicone so it doesn't absorb water (or absorbs it less). Not sure if it handles mechanical mixing any better, but is was fine mixing with a hoe.

Great pic of the oven "resident", Happy Father's Day!

[RandyJ]

Hey david s this is the recommended process from the directions. It is a 2" layer done in roughly 3 layers. The recommended timing for the drying fires is to wait at least 2 days after I finish the 3rd layer. Then I can start the drying fire's.

Do you think I am being to rough with the drill and mixer? I wanted to make sure I was getting everything fully mixed and incorporated. I can get a new mixing tub if you think that is best. My wheel borrow has seen better days and is covered in a rough layers of cement and would be hard to get a even mix.

Randy

[david s]

I’m not sure how thick your recommended perlcrete layer is, but any mix containing either perlite or vermiculite is drastically weakened by its addition. As well as the mix requiring about double the water quantity because the grains soak up so much water. As only a small proportion of the water required in the hydration process it leaves a large amount to be purged. Also perlite and vermiculite grains, being quite weak, will degrade somewhat by mechanical mixers, especially if mixing is extended too much. The recommendation is to fold in gently, preferably by hand (barrow and spade) to avoid the grains being abraded too much. However you should follow the manufacturers instructions. There maybe reasons why the build is done this way. At what stage are drying fires recommended?

[RandyJ]

Today I started on the render coat. The mix is 5,1,1,1 and that is pearllite, Portland cement, Lime,and sand. The first batch i did was a bit to dry and just didn't want to hold together. After that i managed to find roughly the right hydration level. I am using a cordless drill with a mortar mixer to blend the mixture and once it would stick to the upper sides of the 5 gallon bucket it seemed to be about right. It took me about 3ish hours to figure out what i was doing and get this first coat on. It would have sped things up tremendously if I had someone else making up the premix buckets for me. I was using a 20 oz solo cup as my measuring cup. And 10 pearllite scoops seemed like a good volume for the drill to mix. Unfortunately that amount doesn't go super far. Once I had the hang of it then it went well. It was kinda like frosting a cake.

Randy

[Giovanni Rossi]

Well, RandyJ you could have done it the way I did it, or the way a professional would Nice Job!

[RandyJ]

UtahBeehiver yes it will have a breather valve or eventually be just plugged. I had those parts just sitting on my cart so I grabbed them before I came home yesterday. i figured that the galvanized steel would be just fine. And rust should not be a issue as this fitting is used outside in concrete all the time.

Randy

[UtahBeehiver]

That will work as long as you put the breather cap on top and this is not an open end. I forget you are a commercial electrician and have all access to all the conduit fittings.

[RandyJ]

Hey Giovanni Rossi I made up a adapter. What do you think of this. Any reason a all steel set up will be a problem?

[david s]

When filling the pinholes either sift out the course sand and just use a 3:1 mix sand and cement only, colour as you wish, or use a tile grout with a bit more cement in it. I never go down to 3000, I think 800 is plenty, but see how you go and how it looks.

[Giovanni Rossi]

Sorry RandyJ , I forgot what I did until I blew up the photo. I had purchased different fittings before I got to that stage because I wasn't sure what I was going to need. Once I realized I needed only about 2" to get through the final thickness of pericrete layers. I believe I ended up using 2 fittings, 1 female/female and 1 male/male to get close to the right height. It worked out well because I was able to snip out a little of that hardware cloth just enough to allow the male end to "thread" into the cloth. Once the cloth was tied to the chicken wire, everything held in place nicely while I troweled on the pericrete. The bottom fitting was snug against the blanket, ensuring a clear pathway for any moisture/steam.

[RandyJ]

Giovanni Rossi thank you for sharing what you got with me. I just ordered it. I will have to swing through the depot and get a female adapter to do what you did as well. Then I can start the rendering.

david s I appreciate the comments. I am actually pretty surprised how flat it is turning out. There are a few big pock marks that i need to fill in. I am tempted to mix a bit of portland with sand and pigment to fill them in. Should i add some lime in as well or not necessary. I was thinking like 1,1,1 or would more sand be better?

I am guessing that I will need to do another 2 or 3 hrs of grinding to get everything how I want but it is turning out nicely. I also assembled my wet polisher today so I am excited to see how that works. I am having high hopes that it will turn out nicely and I am excited to see how polished I can get it. Not sure how far I should go. It came with up to 3000 grit.

Randy