Let’s get to know basecoat (render) mortar-HUALIAN TOP TECHNOLOGY,Redispersbile polymer powder,RDP

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Let’s get to know basecoat (render) mortar

Release time:

2025-12-12

Basecoat mortar is made by mechanically mixing cement, quartz sand, a polymer binder (redispersible polymer powder, RDP), and various additives. It is mainly used as the crack-resistant protective layer on the outside of the insulation layer in an EPS thin-coat external insulation system (ETICS/EIFS), so it is also called polymer-modified crack-resistant basecoat mortar. It is applied on different types of insulated wall surfaces to form an excellent crack-resistant and water-resistant coating layer. This helps protect the overall performance of the insulation base layer, improves adhesion/compatibility at the interface of the insulation surface, and provides an excellent substrate for the installation of subsequent finishing materials. Basecoat mortar is required to have good workability to make application easier. It also needs high bond strength so that the mortar layer bonds firmly to the substrate, ensuring long-term resistance to cracking and preventing hollowing/debonding and detachment. In addition, when used in humid environments or areas subject to external impact, it should have good water

Let’s get to know basecoat (render) mortar

Basecoat mortar is made by mechanically mixing cement, quartz sand, a polymer binder (redispersible polymer powder, RDP), and various additives. It is mainly used as the crack-resistant protective layer on the outside of the insulation layer in an EPS thin-coat external insulation system (ETICS/EIFS), so it is also called polymer-modified crack-resistant basecoat mortar. It is applied on different types of insulated wall surfaces to form an excellent crack-resistant and water-resistant coating layer. This helps protect the overall performance of the insulation base layer, improves adhesion/compatibility at the interface of the insulation surface, and provides an excellent substrate for the installation of subsequent finishing materials.

Basecoat mortar is required to have good workability to make application easier. It also needs high bond strength so that the mortar layer bonds firmly to the substrate, ensuring long-term resistance to cracking and preventing hollowing/debonding and detachment. In addition, when used in humid environments or areas subject to external impact, it should have good water resistance and strength.

Characteristics of basecoat (render) mortar:

The basecoat layer does not carry structural loads;
The basecoat and substrate must have sufficient bond strength so it will not debond or crack during application or under long-term self-weight and environmental effects;
The basecoat is usually a thin layer and is applied in layers; the finished surface should be flat, smooth, fine, and aesthetically pleasing;
It is mostly used in dry environments and is exposed to air over large areas.