Production materials and waste are usually small next to travel in an event footprint. They are also the two categories an event team controls most directly, and the two with the weakest data.
Travel depends on where attendees live. Energy depends on the venue’s grid. But what gets built, whether it gets reused, and where it goes afterwards are decisions the event team makes, often with the same suppliers year after year.
That makes these categories worth more attention than their share of the total suggests. This article covers what to ask production companies and venues for, the one habit that makes reuse possible, and what to do when the numbers don’t exist.
Why production disappears into one invoice line
Production usually reaches the event team as a single figure. Timber, steel, fabric, print, adhesive, freight to site and disposal are all bundled into one price that says nothing about any of them.
That single line is why the category gets skipped. There is nothing to measure until someone asks for the parts.
It also hides the most useful fact in the whole category: how much of the build was new. A stand made from stock and a stand fabricated from scratch can cost similar amounts and look identical on the invoice, with very different emissions behind them.
What to ask production companies for
Ask for activity data, not emissions. Most production suppliers can’t calculate CO2e reliably, and if one does, you inherit their factors, assumptions and boundaries. Collect the underlying quantities and apply consistent factors yourself, so two suppliers or two years can actually be compared.
| Data point | Why it matters | When to ask |
|---|---|---|
| Material type and weight, by element | The basis for any material-based calculation | Specify as a deliverable at contracting |
| New, hired, or from stock, by element | Separates fabrication from reuse, the biggest lever in the category | Pre-event, from the build schedule |
| Print quantities, substrate and finishing | Print is often the most frequently rebuilt element | Post-event, from the print invoice |
| Freight to and from site: weight, distance, mode | Production freight is often booked separately and missed | Pre-event, confirmed on the invoice |
| End-of-life destination, by element | Stored, reused, recycled or landfilled | At strike, in writing |
The simplest way to get this is to write it into the production contract. A data clause costs nothing at the point of negotiation and is close to impossible to secure after the event.
The strike inventory: the habit that makes reuse possible
The same structure often gets rebuilt every year for a simple reason: nobody recorded what went into storage. Eighteen months later, a partly different team finds it faster to fabricate again than to work out what is already in a warehouse.
That is a records problem, not a design problem. It also means paying twice for the same wall, which tends to be the argument that moves a finance director.
The fix is an inventory taken at strike, the moment everyone least wants to do anything extra. Keep it short enough that it actually gets done. For each element going into storage, record:
- What it is, with a photo
- Dimensions and main materials
- Condition, and anything that needs repair before reuse
- Where exactly it is stored
- Which event it was built for
Assign one named person to own it before the event, not on the day. Then, at the start of planning for the next event, the first question becomes “what do we already have?” rather than “what should we build?”
Getting event-level waste data from a venue
Waste data is held by the venue’s waste or cleaning contractor, and it is rarely offered unless asked for. Ask at contracting, and request it within 14 days of the event.
What to ask for:
- Weight by stream: landfill, recycling and organics, in kilograms or pounds
- The event period only: many venues report waste across the whole building and every concurrent event. If your figure is apportioned, ask how, and record the basis
- Destination by stream: recycling collected is not the same as recycling processed, so ask where each stream actually went
- Surplus food: weight donated, backed by a receipt from the receiving organization
The apportionment question matters most. A building-level figure divided by attendee numbers can look precise while telling you very little about your own event.
When the data isn’t there
Every event has gaps. A stated, consistent estimate holds up. A missing category doesn’t. The GHG Protocol accommodates estimation where primary data is unavailable, provided the method is disclosed and applied consistently.
For these two categories, the defensible defaults are conservative ones:
| Gap | Defensible approach |
|---|---|
| No material weights | A spend-based estimate from the fabrication invoice, with the emissions factor and its source stated |
| Unknown share of reuse | Assume newly fabricated unless reuse is evidenced, for example by an asset register |
| Unknown end of life | Assume landfill unless a diversion record exists |
| No venue waste figures | A per-attendee, per-day waste benchmark for the event type, with the benchmark named |
Two things to avoid. Don’t present an estimate as measured data. And don’t calculate a diversion rate from estimated waste figures and report it as a result: report it as indicative, or not at all.
Reuse is the strongest reduction story in this category, and also the one most often claimed without evidence. If you plan to report it, keep the inventory that proves it.
Turning it into policy
The value of measuring these categories comes from what changes afterwards. Because the event team controls them, a single finding can become a standing rule that applies to every future event:
- Every build is inventoried at strike and stored against the next event
- Production contracts include a data clause covering materials, reuse and end of life
- Venue contracts require event-period waste data by stream within 14 days
Get the checklist. The Event Emissions Data Checklist sets out what to collect across all seven categories, including production materials and waste, who holds each data point, and when to ask. It also covers the accepted fallback for each gap. Get the checklist
Frequently asked questions
- Which scope do production materials and waste fall under?
- For most event organizers, both sit in Scope 3. Under the GHG Protocol, production materials generally fall under purchased goods and services, and waste under waste generated in operations.
- Should I ask suppliers for a CO2e figure?
- No. Ask for activity data such as weights, quantities, distances and destinations, then apply consistent emissions factors yourself. A supplier's CO2e figure comes with their methodology, which you can't check or compare.
- Does hiring count as reuse?
- Hired and stock elements avoid new fabrication, so record them separately from new builds. Report reuse only where you can show which elements came from stock or hire.
- What if the venue only reports waste for the whole building?
- Ask how the figure was apportioned to your event, and record that basis. If it can't be explained, treat the figure as an estimate and say so.
