Lime Plaster Tierrafino Stone preparation

Lime plaster: All suitable substrates for Tierrafino Stone Tadelakt have the same criteria:
-They must act as good mechanical keys, as Tierrafino Stone contains no glue it sets mechanically. This means that the surface of the substrate must be rough, with particles sticking out and with small cavities (1 - 3 mm).
-Substrates should not absorb water too quickly (strong absorbing surfaces should be moistened a lot before applying Tierrafino Stone or they can be treated with Tierrafino Fix).
-To avoid structural cracks, Tierrafino Stone should only be applied onto substrates which do not warp when they come into contact with water contained by the plaster.
-Substrates must not be continually wet.
-Substrates should enable Tierrafino Stone not to dry out too quickly. One of the properties of lime is that it gains strength when it dries out slowly. Keep doors and windows closed during and after application, and prevent any heat sources like heaters, lights and direct sunlight from drying the lime out too quickly.
-any shrinkage or expansion of the background can cause cracks in the surface of the finished lime plaster Tierrafino Stone.
-All substrates are to be clean, dust- and grease free before any new layer, either Tierrafino Stone Tadelakt, concrete or tile glue, is applied. If necessary, ammonia should be used to remove any grease. Click here for the Tierrafino Stone Technical Data Sheet in which you can find a short overview of various suitable substrates.

Tierrafino Base Clay Plaster

Tierrafino Base clay plaster is very suitable as a substrate, but only in dry conditions (not in the bathroom).
The surface of the plastered layer must be left rough.
Should the Base clay plaster absorb water too quickly, prepare the surface with Tierrafino Fix. Tierrafino Fix has, among other properties, a sealing function (please see the Tierrafino Fix page for details and safety advice).

Brick walls

Brick walls are ideal as a substrate for lime plaster Tierrafino Stone.
Brick walls should be prepared by plastering a concrete mix; 1 x part cement, 2-3 x part mason sand and 1 x part gravel of 4 mm, make this layer at least 8 mm thick, leaving the surface of the concrete rough.
Leave the newly applied substrate to dry for at least 24 hrs. before applying lime plaster Tierrafino Stone Tadelakt. Start applying Stone when concrete is hard, but not fully dried out. The surface will gain strength when concrete and Tierrafino Stone dry out together. However, should there be any risc of the substrate cracking, wait 30 days for concrete to dry out fully.

Concrete

Concrete walls are, because of their stiffness, very suitable for Tierrafino Stone.
Very smooth concrete walls: First apply a thin layer of tile glue onto the concrete and roughen this up for it to act as a good mechanical key for the next layer of concrete. Then after sufficient drying time apply a concrete mix; 1 x part cement, 2-3 x part mason sand and 1 x part gravel of 4 mm, make this layer at least 8 mm thick, again leaving the surface rough.
Coarse concrete walls need only be treated with the concrete mix, as described as with brick walls.
Start applying Tadelakt when concrete is hard, but not fully dried out. The surface will gain strength when concrete and Tierrafino Stone dry out together. However, should there be any risc of the substrate cracking, wait 30 days for concrete to dry out fully.

Lime plasters

Onto fresh lime plasters, Tierrafino Stone can be applied after 24 hrs. drying time. Leave the plastered lime rough for it to act as a good mechanical key for Tierrafino Stone.

Plasterboards

Plasterboards are not an ideal substrate as they are very flexible and need a lot of work to make them suitable.
Stick joint tape onto joints and fill joints with joint filler.
Apply primer Tierrafino Contact with a brush.
Since we need to create a "new" structure that is non flexible we advise you to apply a concrete layer of 2 cm thick, in which it is possible to place a metal mesh (a fine mazed chicken wire (approx.1 cm) is very suitable).
Attach the metal mesh every 10 cm to the with Tierrafino Contact covered plasterboards, on the joints (through the plasterboards into the structure below). Then "throw" a concrete mix onto the mesh and make sure there is good adhesion between the tile glue and the concrete. Apply the concrete in stages, as it is impossible to apply 2 cm at once, and leave each consecutive layer rough, to stiffen.
Concrete used needs to be a mix of 1 x part cement, 2-3 x part mason sand and 1 x part crushed gravel of 4 mm. Of course the last layer must also be left rough to achieve the mechanical key for Tierrafino Stone.
Start applying Tadelakt when concrete is hard, but not fully dried out. The surface will gain strength when concrete and Tierrafino Stone dry out together. However, should there be any risc of the substrate cracking, wait 30 days for concrete to dry out fully.

Tiles

Tiled walls are also not an ideal substrate for Tierrafino Stone Tadelakt. They have no absorption and make it difficult to achieve a good finish. Therefore in most cases it is best to remove all tiles.
When working on tiles, clean tiles with ammonia and apply "tile to tile" glue, a glue with good adhesion on porcelain, onto the tiles and spread out with a 4 mm glue comb, then apply the concrete mix of 1 x part cement, 1 x part mason sand and 2-3 x part gravel of 4 mm, make a layer of at least 8 mm thick, again leaving he concrete rough.
Start applying Tadelakt when concrete is hard, but not fully dried out. The surface will gain strength when concrete and Tierrafino Stone dry out together. However, should there be any risc of the substrate cracking, wait 30 days for concrete to dry out fully.

Wood

All wood structures must be covered with plaster board, see plasterboard

Although this product-description has been put together with utmost precision, Tierrafino will not be liable for any indirect or direct damage that may occur, by using the information offered in this product description. With every new edition of this product description, the older versions are not valid anymore.