Alfatherm Top Coat

Description: One compenent cementitious mortar based on high quality cement, selected fine grained sand, special additives and fibers.  

 

Applications: Suitable for levelling the existing integrated fiberglass mesh on thermal insulation panels, on cement boards and gypsum boards prior the application of paint.

Product Identity

  • Appearance: Cement based mortar
  • Color: Grey/White
  • Package & Weight: Bags of 25kg
  • Storage: 8 months in a dry place in original unopened packaging
  • Granulometry: 0 – 0.8 mm

 

Application Data

  • Mixing Ratio: 25kg powder with 6-7 Liters Water
  • Pot life: 3 hours at 23 oC and 50% RH
  • Consuption: 3 – 4 kg/m² of 2 mm thickness/layer (recommended layers: 2)
  • Application Temperature: +5 ºC - +40 ºC

For maximum results, the following steps described below are recommended:

Step 1: For bonding thermal insulation panels on masonry: choose one of the 2 methods of 1(i) or 1(ii) depending on your existing substrate.

       1(i) For substrate without any raised areas or indentations– Full Surface Coating Method:  directly on substrate apply a thin layer of Alfatherm  Base Coat  with the flat side of the trowel. Give thickness to the application by adding the same coating with the notched side of the trowel and install the thermal insulation panels by applying a strong pressure over the panels in order to adhere well with the substrate.

   1(ii) For substrate with little raised areas or indentations – Peripheral Strip & Middle Points Coating Method:

  • For polystyrene panels: apply Alfatherm Base Coat with a trowel at a 4-5 cm strip along the board edges and at 3 spots in the middle with a diameter of about 15cm. Then place the panels on the masonry by applying a pressure over them in order to adhere well with the substrate.
  • For mineral wool panels: in order to obtain an adequate bonding, firstly a kind of primer should be applied with the flat side of the trowel, filling in that way the pores of mineral wool panels. After priming, follow the application process of Alfatherm Base Coat (as described above in method 1 (ii) for polystyrene panels).

In all cases of  Method 1(ii), the mortar should cover at least 40% of the board’s surface.

 

Step 2: For bonding fiberglass mesh on thermal insulation panels: Directly on thermal insulation panel, apply a thin layer of Alfatherm Base Coat with the flat side of the trowel. Give to the application the desire thickness by adding the same coating with a notched trowel of 5mm and embed the fiberglass mesh. Applying pressure to the mess with a flat trowel and leave the material to adequate dry before proceeding to step 3.   

 

Step 3:Surface preparation prior the application of finish coat: follow one of the 2 methods below 3(i) or 3(ii) depending on your choice for the finish coat (elastomeric paint or acrylic textured plaster) 

3(i) Surface preparation when finish coat is elastomeric paint: On the surface, apply 2 layers of Alfatherm Top Coat (about 2mm). Rub the surface when it is still fresh and let the material be sufficiently dried. Now, the surface is flat and smooth. Then prime the surface with Alfaliq Primer and let it to dry completely.

  3(ii) Surface preparation when finish coat is acrylic textured plaster: On the surface, apply 1 layer of Alfatherm Base Coat (about 2mm) and let the material be sufficiently dried. Now, the surface is flat and smooth. Then prime the surface with Alfaliq Grafit Primer and let it to dry completely.

Substrates Preparation

  • The substrate must be flat, strong and clean from dust or oils.
  • For better adhesion the surfaces should be lightly moistened with little water. 

 

Preparing the mix

  • In a clean bucket, add 6 – 7 Litres clean water and 25kg ALAFATHERM TOP COAT.
  • Mixing with a concrete machine or with a low speed electrical mixer until a smooth homogeneous paste is obtained.
  • Leave the mixture to stand for about 5 minutes and mix again.