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Fiber Box containers stacked on a cart in a cold-chain retail environment
Cold-chain packaging

Zero waste.
Zero EPS.
More useful cube.

Fiber Box replaces EPS and waxed corrugated with strong thermal performance and high nesting density. In many lanes, that means measurably better cube and freight efficiency than EPS.

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What are you replacing?

How the formats compare

Below, EPS foam, waxed corrugated, and RENW Fiber Box are compared using our reference assumptions. Your route, product, and how you pack and handle boxes will determine what you see in a real trial — that’s what turns these figures into your numbers.

Total lifetime cost

Legacy

EPS foam

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Typically higher

Standard

Waxed cardboard

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Often higher

The new standard

RENW Fiber Box

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Lower cost in our model

Freight & storage density

Legacy

EPS foam

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1:1

(bulky)

Standard

Waxed cardboard

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>80%

(*)

The new standard

RENW Fiber Box

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~66% to ~80%+

(*)

Regulatory compliance

Legacy

EPS foam

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High risk

Standard

Waxed cardboard

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Repulp risk

The new standard

RENW Fiber Box

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Designed for paper stream**

Thermal integrity

Legacy

EPS foam

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High

(~R-4.0)

Standard

Waxed cardboard

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Low

(~R-0.9)

The new standard

RENW Fiber Box

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Balanced

(~R-1.8)

*Freight savings vs EPS baseline. **Where accepted by local recovery streams.

Packout guidance: medium 5mm Fiber Box

True internal volume

10.5 L (11.1 qt) usable

Material thermal resistance

US R-1.8 (AKD barrier)

Coolant standard

Wet ice or commercial gel packs

Crush resistance

100 kg load

No deformation in PDS; recommended working load: 25 kg

Box dimensions

OD: 15.6" × 11.6" × 6.7"

395 × 295 × 170 mm

ID: 12.2" × 8.58" × 5.9" · 310 × 218 × 150 mm

Lid: 15.55" × 11.6" × 0.78" · 395 × 295 × 20 mm

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Reference lane (proven)

Controlled reefer LTL (US foodservice)

This is the reference lane we’ve run in-market: controlled reefer LTL with a defined time-at-temp and excursion profile, coolant mass, usable volume, and payload band—see the matrix for the published reference row.

How to read the rest

Only the controlled reefer LTL row is in-market reference data. Every other scenario is indicative planning guidance only—gel, volume, and payload must be confirmed in your trial. Longer dwell, hotter ambients, or tougher handling usually require more coolant, coatings, or a different packout.

Product preview

Fiber Box rotating product shot

Reference values

Controlled reefer LTL

(US foodservice · in-market reference)

Environmental load
24 hrs: 40F truck + 4 hrs of 80F excursion
Gel packs required
2.6 lbs
(1.3 qt)
Max usable product volume
9.8 qt
Max fish payload
~19.5 lbs

Indicative — confirm in trial

Ocean freight

(reefer container · starting point · confirm in trial)

Environmental load
14-30 days: 34F container + port excursions
Gel packs required
2.6 lbs
(1.3 qt · confirm in trial)
Max usable product volume
9.8 qt (confirm in trial)
Max fish payload
~19.5 lbs (confirm in trial)

Indicative — confirm in trial

Air cargo

(IR-coated fiber, enhanced barrier · starting point · confirm in trial)

Environmental load
Short-haul air: moderate belly-hold conditions with reduced solar exposure vs. uncoated (indicative)
Gel packs required
Above reference
(lane-dependent · confirm in trial)
Max usable product volume
Below reference (confirm in trial)
Max fish payload
Below reference (confirm in trial)

Indicative — confirm in trial

Air cargo

(standard uncoated fiber · higher-challenge · confirm in trial)

Environmental load
Short-haul air: moderate hold + higher ground-side thermal stress than IR-coated row (indicative)
Gel packs required
Above IR-coated air row
(lane-dependent · confirm in trial)
Max usable product volume
Below IR-coated air row (confirm in trial)
Max fish payload
Below IR-coated air row (confirm in trial)

Indicative — confirm in trial

Non-reefer ambient

(UPS / FedEx Ground · highest-challenge · confirm in trial)

Environmental load
24 hrs: uncontrolled 68F-75F ambient transit
Gel packs required
6.0 lbs
(3.0 qt · confirm in trial)
Max usable product volume
8.1 qt (confirm in trial)
Max fish payload
Payload range TBD (confirm in trial)

Controlled reefer LTL is the only in-market reference lane in this matrix. Ocean freight, air cargo, and non-reefer ambient rows are not substitutes for validation—confirm coolant mass, usable volume, and payload in trial for your lane before relying on any numbers shown.

Performance & logistics

Stop paying for air

Logistic footprint

Fish size (model)

Large (>18 lb avg)

800,000 lb fish / mo (rough)

Truckloads · 0–1000 TL scale (fixed axis)

EPS foam

8.0 TL

1% of scale

Baseline

RENW Fiber

2.0 TL

0% of scale

~4:1 vs EPS (model)

Flat-pack

1.5 TL

0% of scale

Varies by format

Axis is fixed at 1000 TL max so all three bars grow as volume increases. Absolute TL is under each bar; % is share of the 1000 TL scale (capped at 100%).

50,000

Why shippers switch from waxed board

When waxed cardboard gets wet,
the economics fall apart.

Waxed corrugated carton visibly soaked and softened under wet handling conditions

Key checks

Same pairing as the table below: waxed risk, then Fiber Box advantage.

Wet handling

Waxed cardboard risk

Higher risk of wet-down and panel softening

Fiber Box advantage

AKD-sized wall system designed for wet handling workflows

Recovery stream

Waxed cardboard risk

Wax coatings can trigger repulping rejection

Fiber Box advantage

Better aligned to corrugated recovery behavior, with lane verification

Coolant fit

Waxed cardboard risk

Often becomes less reliable as moisture load and dwell time rise

Fiber Box advantage

Supports wet ice or commercial gel packs by lane

Moisture exposure

Waxed cardboard risk

Higher risk of wet-down and panel softening

Fiber Box advantage

AKD-sized wall system designed for wet handling workflows

Recovery pathway

Waxed cardboard risk

Wax coatings can trigger repulping rejection

Fiber Box advantage

Better aligned to corrugated recovery behavior, with lane verification

Coolant integration

Waxed cardboard risk

Often becomes less reliable as moisture load and dwell time rise

Fiber Box advantage

Supports wet ice or commercial gel packs by lane

Stack + handling cycle

Waxed cardboard risk

Greater variability under load, stacking, and saturation

Fiber Box advantage

Qualify with lane SOPs and crush/load safety margin

Ready to upgrade?

Upgrade your flimsy cardboard-only system—we’ll help you validate wet handling, payload, and recovery on your lane.

Validation checklist: dwell time, drainage, stack load, handling cycle, and destination recovery acceptance.

Thermal performance

Controlled meltwater test: Fiber Box loaded with 2 kg of ice to estimate system-level thermal resistance behavior (R-value proxy) under monitored ambient conditions.

Duration
12.4h
External drift
22.8C to 18.7C
Pack core
23.0C to 11.5C
Sample cadence
5 min bins

Temperature profile

5 min bins

24C 20C 16C 12C 8C 0h 4h 8h 12h+ Pull-down cutoff (~1h) Core stabilized window (~4h+)
External ambient Core probe Auxiliary probe Phase cutoff markers Core stabilized reference

Tap Expand for the full-width chart.

Industrial-grade thermal barrier

This chart comes from real temperature logs in a controlled meltwater test (2 kg ice load), plotted every 5 minutes. Treat it as a sanity check — your lane, payload, and packout are what determine the result in practice.

Chart

Innovation &
industrial design

Step 1 of 3

Material system

FSC wood & industrial hemp

Wood fiber and hemp-based pulp options tuned for strength and thermal performance, depending on what your product and lane actually need.

Bio-based fiber blends tuned for strength, thermal hold, and production repeatability.

Dig deeper
Recovery pathway

Curbside paper stream

Designed to fit paper recovery where programs accept it. Local rules vary, so we help you confirm fit for your market.

Built to align with real mixed-paper recovery flows where local programs accept the format.

See end-of-life & EPR
Geometry control

Precision geometry

Precision wall geometry tuned for stack compression, handling, and nest pitch.

Ribbing, wall structure, and nest spacing calibrated for freight density and line handling.

Dig deeper
01. Materials: FSC wood & industrial hemp
02. Recyclability: Curbside paper stream
03. Engineering: Precision geometry
Transgourmet

Seafood shipping:
Transgourmet reference

Transgourmet ran real-world seafood trials comparing Fiber Box to waxed corrugated. The point wasn’t a lab number — it was “does it hold up, stay cold, and survive handling” over the actual trip. Results still depend on the lane and how you pack out.

Need source context? See the PAPACKS/Transgourmet announcement. Read blog post

48h Target cold-chain window
0% Leaching claim (application-specific)
Seafood packing in fiber cold-chain packaging
Fresh transit
Ice and moisture barrier validation
Moisture barrier validation
Industrial fiber box pallet configuration

Who it's for:
industrial scale.

Built for high-throughput hubs where floor space is expensive and waste lines are audited — we’ll pressure-test nesting, pallet patterns, and freight with your network data.

inventory_2
Space reduction Nesting commonly delivers ~66% to ~80%+ cube savings vs EPS baseline, depending on SKU, nesting pitch, and load rules.
local_shipping
Freight efficiency Footprints aligned with common Euro-pallet and ISO container patterns.
deployed_code
E-commerce hybrid lane Supports nested box-in-box architectures (outer insulated panels + inner fiber box) for longer D2C transit windows and porch exposure scenarios.
RENW

Ready to
convert?

Swap out EPS and waxed corrugated without breaking operations. Get samples, run a trial in your lanes, and let’s review the results together.

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