Construction chemicals: Emissions

Why a tiny admixture dose can cut concrete's carbon

Why a tiny admixture dose can cut concrete's carbon What this tab covers The greenhouse-gas footprint per tonne, split by lifecycle phase (feedstock, production, movement, use, end of life), the global total, other environmental impacts, levers and low-carbon routes, India's position, and where the investment opportunity lies. Emission intensity 0.51 t CO2e per t range 0.5-0.7 (EFCA model EPD 2024: 0.514; EFCA eco-profile 2002: 0.69 kg CO2 per kg superplasticiser) · European model EPD for plasticisers and superplasticisers, 1 kg of admixture solution

Per kg of admixture, cradle-to-gate (A1-A3). Intensity: EFCA/Deutsche Bauchemie model EPD EPD-DBE-20230567-IBG2-EN (2024) via SikaPlast-380 declaration; EFCA eco-profile (2002). Global total: not published.

Share of footprint by lifecycle phase

Feedstock 70% Production / process 20% Movement 10%

Footprint by lifecycle phase

Phase	Intensity	Share	Main sources of emissions	Notes	Source
Feedstock	about 0.35 t CO2e per t (indicative)	70%	ethylene oxide and acrylic acid production	EFCA 2002 lists coal, oil and gas inputs of about 16 MJ per kg in total	indicative split of the EPD total
Production / process	about 0.1 t CO2e per t (indicative)	20%	polymerisation heat and electricity		indicative
Movement	about 0.012 t CO2e per t to site (module C2-type value) plus inbound freight	10%	road tankers carrying a product that is 55-70% water		EFCA model EPD 2024 (C2 0.0124 kg/kg); indicative share
Use	negative in effect: enables lower cement content	–	at the 2% maximum dose an admixture adds about 0.010 t CO2e per t of cement (0.02 x 0.514), against about 0.63 t CO2e per t of cement	if it lets a mix use 10% less cement it saves about 0.06 t CO2e per t of cement replaced (indicative)	derived from EFCA model EPD 2024 and cement tile
End of life	about 0.026 t CO2e per t (C4) and -0.044 credit (D)	–	stays in concrete; crushed concrete reused as aggregate		EFCA model EPD 2024

Other environmental impacts

Isocyanate and epoxy exposure; VOCs from solvent-based coatings; microplastic and leachate concerns from some membranes; bitumen fumes.

Levers to cut emissions

Use admixtures to cut cement and water content: cement is about 0.63 t CO2e per t and the world made about 3.8 billion t in 2025 (cement tile)
Admixtures that make high-slag, fly ash and calcined clay cements work, supporting a lower clinker ratio (from 0.76 towards 0.57 by 2050, per Columbia CKI via cement tile)
Bio-based or bio-attributed EO for PCE side chains (indicative)
Renewable power and heat at polymer plants; Sika cut scope 1 and 2 emissions by 6.1% in 2025 (Sika)

India

India makes 470 Mt of cement a year (2025). Wider use of PCE in ready-mix and admixtures for fly-ash and slag blends is a direct route to lower cement per cubic metre (indicative). Company-level admixture footprints for India are not published.

Emission figures are indicative global averages from the life-cycle studies named; actual footprints vary widely by site, energy mix and method.

Low-carbon routes

Route	Intensity	Cost premium	Status	Source
Admixtures for CO2-optimised concrete (EFCA group A model EPD)	0.514 kg CO2e per kg admixture	not published	commercial; model EPD valid to March 2029	EFCA model EPD 2024
Admixtures for low-clinker and limestone calcined clay cements (e.g. Master Builders Solutions MasterCO2RE range)	not published here	not published	commercial in Europe	Master Builders Solutions EPD (MasterCO2RE 3015)

For a climate investor The climate value is in the cement admixtures avoid, not in the admixture's own footprint, which is small. Opportunities: admixtures and grinding aids tuned for calcined clay and high-SCM cements; ready-mix penetration in Indian cities; local PCE macromonomer supply. What has to be true: tenders reward lower embodied carbon per cubic metre (EPD-based), not just strength and price. Sika, Saint-Gobain and Pidilite are the listed exposures.