A good lifecycle assessment consultant can answer extremely detailed questions about one product.
The problem for a distributor is that the customer may ask the same question about 5,000 products.
That is the practical difference between Zilch and a traditional LCA consulting engagement. Zilch is built to create consistent product carbon footprint data across a catalogue. A consultant is built to apply specialist judgement to a defined study, usually with deeper primary data, broader impact categories or independent assurance.
Neither is universally better. The right approach depends on whether you need depth on one product, coverage across thousands, or a combination of software and specialist review.
First: product carbon footprint, LCA and EPD are not identical
These terms are often used as if they mean the same thing.
A product carbon footprint (PCF) quantifies greenhouse gas emissions associated with a product across a defined lifecycle boundary. It focuses on one impact category — climate change — and expresses the result in kilograms of carbon dioxide equivalent.
A full lifecycle assessment (LCA) can assess multiple environmental impact categories, such as climate change, water use, acidification, eutrophication, resource use and toxicity. The exact categories depend on the method and purpose.
An Environmental Product Declaration (EPD) is a standardised, independently verified environmental declaration, generally produced under relevant product category rules and a program operator.
ISO 14067 sets principles and requirements for product carbon footprints. ISO 14040 and ISO 14044 underpin broader lifecycle assessment. The GHG Protocol Product Standard provides guidance for lifecycle greenhouse gas accounting.
Before selecting a tool or consultant, ask what output the buyer actually requested. Paying for a full EPD when a customer needs a credible cradle-to-gate carbon figure can be excessive. Producing a streamlined carbon estimate when a regulated procurement requires a verified EPD can be inadequate.
What a traditional LCA consultant does
An LCA consultant defines the goal and scope, sets the functional or declared unit and system boundary, collects data, constructs the lifecycle inventory, selects impact-assessment methods, interprets results and prepares the report.
The consultant's value is not data entry. It is judgement.
They can decide how to model unusual manufacturing processes, allocate impacts between co-products, handle recycling, choose product category rules, evaluate data quality and defend the study through critical review or verification.
A consultant is often the right choice when:
- The product is technically complex or novel
- Primary manufacturing data is available and material
- Multiple environmental impact categories are required
- The study will support a high-risk public comparative claim
- A customer or regulation specifies an independently verified EPD
- The methodology requires product-category rules or specialist modelling
- One product or a small product family justifies substantial analysis
What Zilch does
Zilch turns structured product inputs into repeatable SKU-level impact data. It is designed for suppliers and distributors managing catalogues rather than sustainability teams commissioning isolated studies.
The workflow captures materials, weights, manufacturing, packaging, transport and branding information, maps those inputs to emission factors and produces a product result with documented assumptions and methodology. Bulk imports, AI-assisted prefilling and matched assessments help apply the same approach across product variants and large ranges.
The results can then be used where buyers need them: tenders, catalogues, product pages, quotes, invoices and customer footprint reports.
Zilch is often the right choice when:
- The business manages hundreds or thousands of SKUs
- Customers need consistent product-level carbon information
- Supplier data is incomplete and requires a governed use of secondary data
- Products and variants need ongoing updates
- Sales teams need outputs quickly
- The data must flow into existing catalogue and order processes
- A full consultant study for every SKU is commercially impossible
Rigour and methodology
A product footprint should not be judged by whether a person or software produced it. It should be judged by the method, data, boundary, assumptions, quality controls and intended use.
Software can improve consistency. The same material, process and transport assumptions can be applied systematically across a portfolio. It also preserves a calculation trail and makes updates repeatable.
Consultants add context-specific judgement. They can investigate unusual inputs, collect primary manufacturing data and resolve methodological questions that do not fit a standardised workflow.
Zilch aligns its product carbon footprint approach with ISO 14067 and the GHG Protocol Product Standard and produces reports documenting inputs, boundaries and methodology. It should not be described as independent third-party verification unless a relevant study or methodology has actually undergone that assurance.
That distinction matters. "Audit-ready" means evidence and calculations are organised for review. It does not mean an auditor has already issued an opinion.
Speed
Traditional LCA projects often take weeks or months because scope, data collection, modelling, review and reporting are completed as a project. That time may be justified for a detailed study.
Zilch's website states that a product assessment can be completed in around 30 seconds once the required product data is available, with catalogue rollouts measured in hours or days rather than months.
The real bottleneck is usually data. If nobody knows a product's material weight or manufacturing location, neither a consultant nor software can invent high-quality primary evidence. Software is faster at processing and standardising available information; supplier engagement is still required to improve it.
Cost and scale
A consulting project includes specialist time for scoping, data collection, modelling, analysis and reporting. Publicly quoted ranges vary widely, but detailed LCA and certification projects can cost thousands or tens of thousands of dollars per product.
That can make sense for a high-revenue product, regulated category or public EPD. It does not make sense for a distributor with 20,000 relatively low-value SKUs.
Software changes the economics by reusing the calculation system, emission-factor library, data model and product relationships. Similar products and variants can share validated inputs rather than starting from a blank page every time.
The relevant measure is not only cost per study. It is cost per SKU kept current and delivered to a buyer.
Data quality
Consultants usually try to collect specific primary data for the processes most material to the study. Where primary data is unavailable, they use secondary datasets and clearly document the limitations.
A scalable product platform also needs a data hierarchy. A sensible approach is:
- Supplier-specific product and manufacturing data where available
- Verified certificates and test reports
- Product-category or regional averages
- Conservative secondary assumptions for unresolved gaps
- Clear quality and confidence flags
The worst outcome is not the use of secondary data. It is presenting an estimate as perfect primary data.
For distributors, coverage and accuracy must improve together. Start with consistent estimates across priority ranges, identify the assumptions driving results, then engage suppliers to replace the most material secondary inputs.
Updating results
A consultant report is usually a snapshot. When the material, factory, energy mix, packaging or transport route changes, the study may need to be updated as a new piece of work.
Zilch treats the footprint as product data. Inputs can be updated and results republished through customer-facing channels. That is a better fit for catalogues where suppliers, products and evidence change continually.
Version control remains important. Buyers should be able to see when a result was calculated, which product version it applies to and what boundary was used.
Communication and sales use
Consultant reports are often written for sustainability specialists, reviewers or program operators. They can be technically strong but difficult to insert into a quote due tomorrow afternoon.
Zilch is designed around commercial outputs. A distributor can use the same governed data in a tender attachment, product page, quote, invoice or customer order footprint.
This is not cosmetic. Sustainability data creates commercial value when it reaches the purchasing decision. A detailed report that nobody outside the sustainability team can find has limited sales utility.
When you need independent assurance
Independent assurance may be required when:
- A regulation or tender specifies it
- You are publishing an EPD
- You are making a comparative public claim
- The result is financially or reputationally material
- A major customer's methodology requires verification
In those cases, use an appropriately qualified verifier and the applicable standard or program rules.
For lower-risk internal comparison, tender support or portfolio screening, a transparent and consistently applied product carbon footprint may be proportionate without verifying every SKU individually.
The decision should be based on intended use and claim risk — not on the assumption that every number needs the most expensive possible study.
The hybrid model
For many suppliers and distributors, the best approach is software plus targeted specialist review.
Use Zilch to build the product-data foundation, cover the catalogue and identify high-impact or high-value products. Then use consultants or assurance providers for:
- Methodology review
- Complex product families
- Primary-data studies
- EPDs
- Comparative claims
- Customer-mandated verification
This concentrates expert time where judgement changes the decision, rather than paying consultants to repeat the same data-processing work across minor variants.
Questions to ask before choosing
- What exact output has the buyer requested?
- Is the focus carbon only or multiple environmental impacts?
- How many products must be covered?
- Will the results need regular updates?
- What primary supplier data exists?
- Does a standard, PCR, tender or regulation require verification?
- Is the result for internal screening, B2B data sharing or a public claim?
- Where must the output appear?
- Who will maintain the data after the initial project?
- What level of uncertainty is acceptable for that use?
The verdict
Use an LCA consultant when the product, claim or regulatory use justifies specialist depth and independent scrutiny.
Use Zilch when the problem is scale: thousands of products, repeated customer requests and a need to put consistent impact information into everyday sales channels.
Use both when you need portfolio coverage with targeted depth on the products that carry the most risk or commercial value.
If one-off LCAs cannot cover your catalogue, see how Zilch creates product impact data at SKU level.