Calcium formate is the calcium salt of formic acid with the chemical formula Ca(HCOO)₂. It appears as a fine white to grey powder, virtually odorless. It dissolves well in water (approximately 16 g per 100 mL at room temperature) and decomposes at about 300 °C. The substance is hygroscopic and actively absorbs moisture from the air.
Calcium formate is non-flammable, non-explosive, and chlorine-free.
| Parameter | Value |
| Chemical formula | Ca(HCOO)₂ |
| Active substance content | ≥ 98% |
| Appearance | Fine white to grey powder |
| Odor | Virtually none |
| Solubility in water at 20 °C | ~16 g / 100 mL |
| Moisture content | ≤ 0.5% |
| Decomposition temperature | ~300 °C |
| Chlorine content | None |
| Flammability | Non-flammable |
| Explosiveness | Non-explosive |
Calcium formate is supplied in 25 kg bags.
Calcium formate is successfully used in concrete (both reinforced and non-reinforced), various types of plasters, tile adhesives and grouts. It ensures reliable hardening at sub-zero temperatures, accelerates strength gain, and being chlorine-free, is completely safe for steel reinforcement and does not cause efflorescence on surfaces.
For concrete applications, the recommended dosage is 2–4% by weight of cement. In dry building mixes such as tile adhesives and plasters, the dosage is lower — 0.5 to 2% by weight of the total mix. The exact amount depends on the required hardening speed and ambient temperature: the colder it is, the closer the dosage to the upper limit. The additive is pre-mixed with dry components or dissolved in mixing water for uniform distribution.
Yes, it is compatible with most plasticizers and superplasticizers. However, before full-scale use, it is advisable to test compatibility with specific admixtures in laboratory conditions, as some combinations may affect setting time and mix workability.
The main advantage is the complete absence of chlorine. Chloride-containing admixtures cause corrosion of steel reinforcement and are prohibited in reinforced structures. Calcium formate is absolutely safe for metal, environmentally friendly, and does not cause efflorescence on the concrete surface, preserving its appearance and durability.
Store in a dry, covered, well-ventilated area, protected from direct sunlight and moisture. Bags must be tightly sealed, as the substance is hygroscopic and readily absorbs moisture from the air, which can lead to caking and reduced effectiveness. Although calcium formate itself is non-flammable, open flames in storage areas are undesirable due to the easily ignited paper and polyethylene packaging.