How we estimate the CO₂e our surplus tiles help avoid

HOMA2u sells surplus tiles: end-of-line, excess and overstock tiles that have already been made. When a customer chooses one of these tiles instead of a newly manufactured one, the emissions of making that new tile can be avoided. Our counter is an estimate of those potentially avoided emissions. This page explains exactly how we calculate it and what it does and does not mean.

The calculation

Tiles sold (m²) × 19.65 kg CO₂e per m² × 65% = estimated CO₂e potentially avoided

• Tiles sold (m²): only surplus tiles count. Every surplus product is marked as overstock (OS) on its product page and carries an item code starting with "OS". We count a sale only when it appears on a confirmed invoice in our accounting system (Xero) with an OS item code, so regular (non-surplus) tiles are never counted. We count by the number of OS pieces on the invoice, not by price. The pieces sold are then multiplied by the area of each piece as stated on its product page. We count sales from 1 April 2026, the start of our financial year.
• 19.65 kg CO₂e per m²: the emissions from making one square metre of porcelain tile, from raw materials to the factory gate (life-cycle stages A1 to A3). This figure comes from the third-party verified Environmental Product Declaration of Niro Ceramic Group for porcelain tiles made at its plant in Shah Alam, Malaysia (SCS-EPD-08646, valid 30 January 2023 to 29 January 2028). We use it because it is a current, verified, Malaysian figure. Published figures for tiles made elsewhere range from about 6 to 20 kg CO₂e per m², so tiles from other factories may be higher or lower.
• 65%: not every purchase of a surplus tile replaces the purchase of a new tile. Some buyers might not have bought tiles at all. Following research on resale by WRAP (Displacement Rates Untangled, which found that 64.6% of resale purchases replace a new purchase), we count only 65% of sales as replacing new tiles.

The total is shown in kilograms (kg) of CO₂e, rounded down to the nearest 100 kg, together with the m² of surplus tiles sold, and updated once a month.

What we leave out

• We count only the emissions of making the tile. We do not add savings from transport, installation or disposal, because a new tile would need those too.
• We do not claim any saving from landfill. Ceramic tile is inert, so landfilling it has almost no direct carbon impact.
• We do not add or subtract the delivery of the surplus tiles to our warehouse. This is a known limitation of the estimate.

What this figure is not

• It is an estimate with real uncertainty, not a measured value. Actual savings depend on each tile's factory, thickness and what each customer would otherwise have bought.
• It is not a carbon offset, and HOMA2u does not claim to be carbon neutral or net zero.
• These are emissions potentially avoided by our customers' choices. They are separate from, and are not deducted from, HOMA2u's own emissions or our customers' reported emissions.
• The figure has not been independently verified.

Sources

• Niro Ceramic Group, Environmental Product Declaration for porcelain tile, SCS-EPD-08646 (SCS Global Services, 2023): niroceramic.com
• WRAP, Displacement Rates Untangled: wrap.ngo
• WBCSD, Guidance on Avoided Emissions, which informs how we report this figure: wbcsd.org

Method version 1.0. Last updated: 1 October 2026. Questions about this estimate? Contact us and we will share the details.