celestine

Can someone tell me how I will know if my walls are painted with this and how safe it is to use? Thanks

snikpoh

It's very safe to use but you MUST know what you are doing! (cal = lime)

Not sure how you can tell if your walls are plastered with lime plaster though or simply painted with lime wash/paint - sorry.

Fredbargate

Cal is whitewash, it is made from lime, if you wet the walls thoroughly the white will go transparent and the underlying colour will show through. Also it tends to flake off after a few years depending on weather conditions.

The HSE would probably condemn it, then given the chance they would condemn birth because that is the start of all lifes dangers. It has been used all over the world for centuries and is good at deterring fungus and small annoying insects etc.

I have been using it on my garden walls for 25 years, however I found some exterior paint in Le Roys this year that was so cheap I am now using it.

JulianWard

If you wet a finger and put it on the paint, if you see the damp mark of your finger it is cal or Artex. If not it is plastic.

An advantage of Artex is that it is porous thus if you get damp in the wall it will not flake off as plastic would, and it will normally dry back to white again.

You can paint plastic on a wall previously painted with cal or Artex but not vice versa.

If using cal take care as it is corrosive. Artex is a better choice

Caution Asbestos.

Quote:-

Ceiling Artex

Old decorative ceiling coatings like 'Artex' often had small amounts of asbestos added to the material to improve strength. Generally if ceilings are in good condition, they can be left alone and 'managed in situ' by annual inspection and maintaining a good paint covering.

celestine

Many thanks for all your advice, very informative. I shall now trot off and have a look upstairs.

bil

I had a customer who used proper authentic lime based paint in an old house. Unfortunately a small splash got in his toddler's eye and blinded him, so be very, very careful if using it.

Also, from personal experience, tiny, dry chips that get in your eye are deeply painful, so use eye protection.

JulianWard

Cal is :- calcium hydroxide

angiescarr

I'm a big fan of Cal (lime). Not just for paints for breathable walls, but also for lime plaster for repairing old soft construction walls. In Spain you don't seem to be able to be able to get the tubs of mature slaked lime and I must admit I don't know if sacks of cal are only partially slaked(this is what I'd guess) meaning it's more chemically active than a properly slaked lime. (It gets warm/hot when you add water).
Someone else has said it beats off mould. I second that and add bacteria as well. It's consequently really good for old fashioned pantries and animal houses etc. The Victorians used to paint the underneath of the floorboards in their cellars to help keep rot/mould away.
Cal paint is also good for keeping bugs and infections off your fruit trees.
I've seen bags of cal putty properly slaked for this in some Ferreterias.
As another poster said, just keep it out of your eyes. But don't be too scared of flakes. Just brush them off, wearing goggles, though they aren't as dangerous as the fresh product.
Incidentally (in England particularly)if you find your bricks are crumbling after a new re-pointing job, hack off the re-pointing (usually done with hard cement) Cut out and turn round the dodgy bricks and re-point again with a lime based mortar. This can also happen to newly repaired Spanish houses, completely blowing off the new render. Hard cement bad... lime cement good on old houses (over 100 years old as a generalisation). (IMO)