Mattresses

Material Composition Assumptions

The default reference product is a queen-size innerspring mattress with polyurethane foam comfort layers, weighing approximately 30 kg, composed of:

• Polyurethane foam: Flexible PU foam (comfort layers and edge support), approximately 8-12 kg. Produced from toluene diisocyanate (TDI) or methylene diphenyl diisocyanate (MDI) reacted with polyester or polyether polyols. Blowing agents (water-blown or chemical-blown) create the cellular structure.
• Steel spring unit: Bonnell coil or pocketed coil spring system, approximately 8-12 kg of tempered steel wire. Wire gauge typically 13-16 gauge (1.6-2.3 mm diameter).
• Fabric cover: Quilted textile cover with polyester wadding, approximately 3-4 kg. Typically polyester-cotton blend with fire-resistant treatment.
• Additional layers: Fiber padding, felt insulator pads, and edge reinforcement, approximately 2-4 kg.
• Packaging: Polyethylene bag, cardboard corners, and stretch wrap, approximately 1.5-2 kg. Bed-in-a-box models use compressed roll-packing with additional cardboard.

Polyurethane foam is the dominant emission driver due to the petrochemical intensity of isocyanate and polyol production. The PU foam precursors (TDI/MDI) are among the most carbon-intensive plastics by mass.

Manufacturing Geography

Mattress manufacturing is more regionalized than most consumer goods categories due to high transport costs relative to product value:

• USA: Approximately 90% of mattresses sold in the US are manufactured domestically. Major producers include Serta Simmons, Tempur Sealy, and numerous regional manufacturers.
• China: Dominant exporter for compressed/rolled mattresses (bed-in-a-box format). Growing domestic market.
• EU: Major production in Poland, UK, Germany, and Belgium. EU manufacturers serve regional markets.
• Grid intensity (China): 565 gCO2e/kWh (IEA 2024). Used as the conservative default for export-oriented production.
• Grid intensity (USA): 390 gCO2e/kWh (IEA 2024).
• Rationale: Foam pouring is an exothermic chemical reaction that requires controlled environments but relatively little electricity. The major energy inputs are in upstream chemical production (Scope 3) and steel spring manufacturing.

Regional Variation

Manufacturing Region	Grid Intensity	Estimated CCI Score	Adjustment vs Default
China (default)	~565 gCO2e/kWh	85 kgCO2e	Baseline
USA	~390 gCO2e/kWh	80 kgCO2e	-6%
EU average	~300 gCO2e/kWh	77 kgCO2e	-9%
Poland	~640 gCO2e/kWh	87 kgCO2e	+2%
UK	~210 gCO2e/kWh	75 kgCO2e	-12%

Note: Because Scope 3 (upstream chemical and steel production) dominates at 73% of total emissions, regional grid variation has a proportionally smaller effect on the total score than the chemical supply chain.

Provenance Override Guidance

A supplier or brand may override the default CCI score by submitting:

1. Environmental Product Declaration (EPD) or Product Carbon Footprint (PCF) per ISO 14067 covering materials through finished mattress.
2. Foam chemistry data: Bio-based polyols (soy-based, castor oil-based) can reduce foam-stage emissions by 10-25%. Natural latex (Hevea rubber) as an alternative to PU foam has different emission profiles.
3. Steel sourcing data: Electric arc furnace (EAF) steel with high recycled content (70-100%) can reduce spring-unit emissions by 50-60% compared to basic oxygen furnace (BOF) steel.
4. Factory energy data: Foam pouring and curing energy, quilting line electricity, and packaging energy.
5. CertiPUR-US or OEKO-TEX certification supports verification of foam chemistry but does not directly address carbon footprint.

Methodology Notes

• CCI score of 85 kgCO2e represents a conservative estimate for a queen-size innerspring+foam mattress. Belboom et al. (2015) report 70-100 kgCO2e for comparable mattresses, and the CCI score sits in the upper range to account for conservative grid assumptions.
• Scope breakdown: Scope 3 dominates at 73% (62 kgCO2e), driven by PU foam precursor production, steel wire manufacturing, and textile production. Scope 2 is 18% (15 kgCO2e) from factory electricity. Scope 1 is 9% (8 kgCO2e), unusually high for this category due to the exothermic foam pouring process and on-site thermal energy for foam curing ovens.
• Functional unit: One queen-size mattress (~30 kg), cradle to gate through packaged product.
• Confidence: Low because mattress construction varies enormously — from all-foam to hybrid to all-latex to airbed — and limited peer-reviewed LCA data exists for the category. The Belboom et al. study is one of few published mattress LCAs.
• Data gaps: All-foam mattresses (memory foam, bed-in-a-box) may have 10-20% higher PU content and lower steel content, resulting in similar total emissions but different scope breakdown. Latex mattresses use natural rubber with different upstream emissions (plantation agriculture rather than petrochemicals).