Blue grit, often referred to colloquially as "blue grit paint" due to its blue color and liquid application, is a type of high-performance bonding agent primarily used in plastering. Its main purpose is to prepare challenging, smooth surfaces, creating a suitable base for subsequent plaster coats to adhere to firmly.
Understanding Blue Grit as a Bonding Agent
According to the provided reference, products like Feb® Febond Blue Grit® are defined as a high performance plaster bonding agent specifically designed to provide an improved key to smooth surfaces. This means it acts as an intermediary layer that ensures plaster sticks effectively where it otherwise might not.
How Does Blue Grit Work?
Traditional plaster requires a "key" – a rough or absorbent surface profile – to bond properly. Smooth or non-porous surfaces lack this key. Blue grit solves this problem by providing a physical key. The reference states, "Containing a fine aggregate, Feb® Febond Blue Grit® provides a mechanical key to backgrounds such as plaster, concrete, painted surfaces and glazed tiles." The fine grit within the bonding agent creates a textured surface profile once applied and dried, giving the plaster something physical to grip onto.
Typical Applications
Blue grit is particularly useful on surfaces that are too smooth, non-absorbent, or potentially unstable for direct plaster application. Common backgrounds where a product like Feb® Febond Blue Grit® is applied include:
- Existing smooth plaster
- Dense concrete
- Previously painted walls or ceilings
- Smooth, non-porous surfaces like glazed tiles
By applying blue grit, you create a reliable surface that promotes strong adhesion, preventing issues like cracking, delamination, or poor bonding of the new plaster layer.
Key Features of Blue Grit
| Feature | Benefit / Description |
|---|---|
| Bonding Agent | Creates a strong connection between challenging surfaces and plaster. |
| Contains Grit | Provides a physical, mechanical key for plaster adhesion. |
| High Performance | Suitable for difficult, smooth, or non-porous backgrounds. |
| Blue Color | Easily visible during application to ensure full coverage. |
In summary, "blue grit paint" is a common term for a specialist bonding primer like Feb® Febond Blue Grit®. It's essential for preparing smooth or difficult surfaces before plastering to ensure the new plaster bonds securely and durably.
