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This deals with the use of colored cement as a paint to colorize cement structures.
Humidity passing through a cement roof can cause ceiling paint to blister and peel. Not so with colored cement, which sticks like crazy to cement, even wet. With luck, an interior cement "paint" job is a lifetime paint job.
On the outside, cement paint helps seal cracks.
I use a pressure sprayer for preliminary cleaning.
One interesting advantage to using cement as paint is that spiders appear to not like raw cement. There are very few spider webs where surfaces are painted with cement. If you paint them with house paint, the spiders come. Some insects (butterflies?) taste through their feet, I think. Although not insects, that may explain why spiders don't like to hang out on raw cement. Whatever the reason, fewer spiders in the house is good. Fewer cobwebs to clean results in less time spent cleaning.
Humidity passing through a cement roof can cause ceiling paint to blister and peel. Not so with colored cement, which sticks like crazy to cement, even wet. With luck, an interior cement "paint" job is a lifetime paint job.
On the outside, cement paint helps seal cracks.
I use a pressure sprayer for preliminary cleaning.
One interesting advantage to using cement as paint is that spiders appear to not like raw cement. There are very few spider webs where surfaces are painted with cement. If you paint them with house paint, the spiders come. Some insects (butterflies?) taste through their feet, I think. Although not insects, that may explain why spiders don't like to hang out on raw cement. Whatever the reason, fewer spiders in the house is good. Fewer cobwebs to clean results in less time spent cleaning.
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Signing UpStep 1Materials
The basic materials needed are cement and pigments to colorize the cement. Concrete acrylic fortifier can also be added to improve bonding and perhaps weather resistance on exterior surfaces. I'm not sure if adding acrylic fortifier decreases the spider-repelling properties of the cement. For interior painting it may not be as important to use it, anyway.
I use both regular gray Portland cement and white cement, depending on the colors I am after. For darker colors, I use gray cement. The more pigment you use, the more intense the colors will be. The cement is the binder, though, so an excess of pigment could mean not enough binder and result in a chalky surface.
Pigments for cement come in liquid and powder form. I prefer the dry powder form, since I can mix the pigments with cement and store them for later use. (Water in the liquid pigments would harden up the cement.) One way to mix the different powders is to put them in a closed container, such as a plastic bucket with lid, and shake them.
Unlike the powdered pigments available from some art supply stores, the pigments from hardware stores are more limited in color, and a lot less expensive. Red is sort of a "red oxide", yellow is sort of ochre. There is also a green, blue, and black. With those basic colors, which are not true primary colors, you can mix a range of colors.
This Wikipedia link will tell you way more than you need to know about Portland Cement. http://en.wikipedia.org/wiki/Portland_cement
I use both regular gray Portland cement and white cement, depending on the colors I am after. For darker colors, I use gray cement. The more pigment you use, the more intense the colors will be. The cement is the binder, though, so an excess of pigment could mean not enough binder and result in a chalky surface.
Pigments for cement come in liquid and powder form. I prefer the dry powder form, since I can mix the pigments with cement and store them for later use. (Water in the liquid pigments would harden up the cement.) One way to mix the different powders is to put them in a closed container, such as a plastic bucket with lid, and shake them.
Unlike the powdered pigments available from some art supply stores, the pigments from hardware stores are more limited in color, and a lot less expensive. Red is sort of a "red oxide", yellow is sort of ochre. There is also a green, blue, and black. With those basic colors, which are not true primary colors, you can mix a range of colors.
This Wikipedia link will tell you way more than you need to know about Portland Cement. http://en.wikipedia.org/wiki/Portland_cement
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After shaping the dirt, I splashed it with a soupy mix of cement and water with a big brush to make an egg shell-like layer of cement on the dirt. When that dried, I plastered the walls, without fishnet, embedding staple-shaped pieces of galvanized tie wire -- the points sticking outward from the cement.
When that hardened, I used the wire legs to hold the fishnet in place while I plastered it. The wires prevent a run-away failure if some of the cement lets go and pulls the net, which can make everything fall down. Because of the wires, the run only goes so far and stops.
After that layer hardens up, you can paint it with tinted cement. I did a first coat of yellow, followed by a couple splash coats of other colors and a final touch-up with a textured roller.
Cement from the ceiling falls on the floor, so you plaster the floor after plastering the ceiling.
Here are some recent photos.
How are your zipper steps holding up now that they've gotten some use and some weather?
I don't see that the fish net you use offers much in the way of anything with the very real exception that when you cover it with a layer of cement, you are guaranteed to have a layer that is as thick as the netting. Otherwise the coat might be thin and thick in spots.
Pressure clean the area first.
One part cement. One part sand for non-slip texture. Pigments.
Brush it on with a broom head, scrubbing to work it into the pores of the old cement.
Best to work in the late afternoon, after the heat of the day, letting it harden overnight. If it dries out too fast, it dries chalky. Spray mist with a hose if you see it drying out too fast.
. Other than adding the pigment(s), follow the same procedures you would use for building any sidewalk (eg, forming, reinforcing, &c).
. As Thinkenstein points out, too much pigment will probably weaken the concrete.
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. BTW, very creative job with the pressure cleaner. Didn't happen to get pics for an iBle did ya?
The phone for your mum works now by the way. Building a case for it this week then submitting it. Should be building a cheaper, more flexible version in the next few months.