Frequently Asked Questions

Primarily in unbound layers: 

• Ecoblend Type 1 (SHW Clause 803) for sub-bases under roads, car parks, yards, footpaths 
• Ecoblend 6F4 and 6F5 (SHW Clause 613) as capping/general fill to improve weak ground and build levels 
• Platforms, embankments and hard standings.
  Bound uses (e.g., hydraulically bound mixtures/asphalt base) are project specific. IBAA is not used as the exposed surface; it must be covered 

Yes. Using IBAA-containing products reduces embodied carbon versus natural aggregate and helps meet recycled content requirements (e.g., BREEAM-aligned procurement). Because IBAA is lighter by volume, fewer lorry movements may be needed for the same coverage. Ecoblend can provide indicative data to support tenders and client reporting. See our article on Why Less is More to understand the impact of volumetric efficiency on material savings. 

Ecoblend materials are produced to recognised standards, including BS EN 13242 (unbound/hydraulically bound materials) and BS EN 13285 (unbound mixtures such as Type 1). They are engineered to satisfy SHW Clause 803 (Type 1 sub-base) and SHW Clause 613 (capping classes such as 6F5), with supporting test data available. 

Typically, no – you usually need ~10–15% less tonnage of Ecoblend products due to IBAA’s lower bulk density (often ~2.0 t/m³ vs ~2.3–2.4 t/m³ for many primaries). That means fewer tonnes to handle and fewer deliveries for the same volume. Ecoblend provides conversion factors to aid estimating. 

Yes. Pricing for recycled aggregates is often lower per tonne than primary. Additional advantages include Aggregates Levy relief and potential haulage savings due to proximity. Coupled with the lower tonnage required per m³, Ecoblend can deliver tangible material cost efficiencies. 

Treat like other crushed recycled aggregates: 

• Deliveries are typically slightly damp to aid compaction; add light water if deemed too dry. 
• Place in 150–250 mm lifts; compact with standard vibratory plant to target density/CBR.
• Use dust suppression in dry conditions and always cover with asphalt, concrete, or paving.

Your Ecoblend supplier can provide method guidance and typical compaction parameters. 

In England, Environment Agency RPS 247 sets out how unbound IBAA can be used without a waste operation permit when conditions are met (non-hazardous, BS EN 13242 compliant, approved applications, not in sensitive locations).  

Ecoblend MA and Ecoblend CA contain Incinerator Bottom Ash Aggregate (IBAA), which cannot be used in environmentally sensitive areas, such as Sites of Special Scientific Interest (SSSI), and therefore needs to be used according to the Environment Agency’s Regulatory Position Statement 247. A reputable supplier will complete these checks for you and return all relevant documentation. 

Incinerator Bottom Ash (IBA) is the non-combustible residue from Energy-from-Waste (EfW) facilities. At specific Day Aggregates sites (Avonmouth, Brentford, Greenwich, Wellingborough) it is aged, metals are recovered, and the mineral fraction is crushed, screened and graded. The result is Incinerator Bottom Ash Aggregate (IBAA) – a granular, stable material that looks and performs as quarried aggregate and has been used successfully for over 20 years. Ecoblend uses IBAA within specification compliant products such as Ecoblend Type 1 and Ecoblend 6F4 and 6F5. 

No. When processed, IBAA is routinely classed non-hazardous. Only non-hazardous IBA (waste code 19 01 12) is accepted; the material is aged to stabilise it and tested (pH, leachability, heavy metals). It must be used in approved applications and locations; Ecoblend materials are supplied to locations that meet the Environment Agency RPS 247 criteria.

• Landfill diversion: ~530 kg of municipal waste avoided per tonne of IBAA produced. 
• Resource preservation: each tonne of IBAA can replace ~1.1–1.3 t of quarried material 
• Lower transport emissions: EfW/processing is often close to urban projects. Material savings result in fewer lorry movements reducing carbon outputs.

Choosing Ecoblend supports circular economy goals with traceable recycled content 

• Clause 803 defines Type 1 sub-base requirements (grading, fines, plasticity, etc.). 
• Clause 613 covers selected granular fills/capping (e.g., 6F4, 6F5).

IBAA is recognised as a manufactured aggregate that meet these specifications. Ecoblend Type 1 and 6F4 and 6F5 are designed to comply. 

In unbound applications, IBAA meets the same performance intent as primary stone when produced to spec: it compacts efficiently, provides reliable load-bearing capacity, and is non-frost-susceptible when correctly placed. A mild pozzolanic effect can increase stability over time. Ecoblend’s production control underpins consistency on site. 

Yes. Around 3 million tonnes are used annually across UK construction. It’s accepted by National Highways and many local authorities when materials meet the relevant specifications. Ecoblend Case Studies are available for highways, logistics, residential and public-realm schemes. 

MIBAAA (Manufacturers of IBA Aggregates Association) represents producers, publishes best practice, and works with regulators on quality and End-of-Waste pathways. Ecoblend is produced under licence from Day Group, a member of MIBAAA, aligning with recognised standards and factory production control. To learn more about MIBAAA and the role it plays in the industry, visit their website.