Packaging Guidelines

These guidelines can be useful when discussing or planning boxes of many kinds.


From Graphical to Packaging and Recycled.

We stock a wide range of Packaging, Graphical and Uncoated Boards. Recycled Grades, Covering Materials, Speciality and Decorative Materials.

Our range of packaging, graphical and uncoated boards are perfect for a wide array of uses including: printed cartons, corrugated cases, greeting cards, point of sale displays, postcards, boxes, packaging solutions, calendars, games, books & much more.

Board Classification/Types:

Code Description
G Coated
GG Cast Coated
GZ Coated Solid Bleached Board
GGZ Cast Coated Solid Bleached Board
GN1 Coated Solid Unbleached
GG1 Cast Coated Folding Box Board White Back
GG2 Cast Coated Folding Box Board Manilla Back
GC1 Coated Folding Box Board White Back
GC2 Coated Folding Box Board Manilla Back
GT Coated Chip Board Manilla or White Back
GD Coated White Lined Chip Board with Grey Back
GD1 Coated WL Chip Board (high bulk, >1.45**)
GD2 Coated WL Chip Board (medium bulk, less than 1.45)
GD3 Coated WL Chip Board (low bulk, < 1.3)
K Uncoated Kraft fibre Board
T Test – Partly recycled
U Uncoated
UN Uncoated Unbleached Board
UZ Uncoated Solid Bleached Board
UC1 Uncoated Folding Box Board White Back
UC2 Uncoated Folding Box Board Manilla Back
UT Uncoated Chip Board Manilla or White Back
UD1 Uncoated Chip Board Top Liner Woodfree
UD2 Uncoated Chip Board Top Liner Near Woodfree
UD3 Uncoated Chip Board Top Liner Partly Mechanical

** Bulk is calculated by dividing thickness in microns, by gramme weight e.g. 304microns/250gsm = 1.2

Quality Characteristics:

Terminology Description
Thickness (also called ‘caliper’) Measured in microns, 1000 microns = 1mm
Grammage (also called ‘substance’) Weight, measured in grammes per square metre (g/m²)
Stiffness The bending resistance of a board – always higher in machine direction than cross direction. Measurement: Taber. Bending a strip of board over a 15º angle. The higher the percentage the glossier the surface.
Gloss Surface reflectance of a coated surface. Measurement: Hunter, expressed as a percentage of reflected to incident light, shone at 75º from the plane of the surface. The higher the percentage the glossier the surface.
Smoothness Surface smoothness of a board. Measurement: PPS or Bendtsen, measures the amount of air leaking out from a flat measuring head under constant pressure. Express in ml/min or microns peak/trough. The higher the value the rougher the board.
Brightness Measures the blue/white resistance. Measurement: ISO and express as percentage of standard value. The higher the percentage, the brighter the surface.

Detailed product information sheets can obtained on request.


Corrugated Boards

Corrugated cardboard is basically made up of a fluted sheet which is sandwiched between an outside liner and an inside liner. It is the size of the flute and the weight of the paper, which between them, determine the strength and the performance of the packaging.

If you ask a cardboard manufacturer for a specification, it will look something like this:-
150K/B/150T (for a single wall)
150K/BC/150T (for a double wall)
150 refers to the weight of the outside liner paper, K refers to type of liner, B refers to the flute and 150 refers to the weight of the inside liner paper, T refers to the type of liner.
Liner Papers
Standard paper weights are
125gsm – Light standard grade
150gsm – Common/medium/postal grade
200gsm – Heavier/durable board
300gsm – Very strong board
Common paper grades are:-
K = Kraft (Virgin kraft paper – the strongest form of paper and suitable for printing)
T = Test (Partly recycled)
The main standard flutes for packaging are B and C:-

B = 3mm board thickness (the most widely used due to its all-round compression strength
C = 4mm board thickness (a larger flute than ‘B’ offers greater compression strength, but more easily crushed)
BC = 7mm board thickness in total (used when compression and stacking are important) – double wall
Corrugated Walls

Single Wall: Made from a single layer of B flute with two liners
Double Wall: Made from a single layer of B flute, a single layer of C flute and three liners (BC)
Packaging required is based on a number of factors and the main factors to consider are:-

  • Weight of the product to package
  • Will the product fill the packaging? The less void, the better they perform
  • How they are to be stacked on a pallet
  • The trust of the carrier not to mishandle the product



  • Height or Depth
  • Width or Length.
  • Depth
  • Internal & External

Unfortunately, depending on one’s perspective, some of these terms are interchangable, Height can be the same as Depth if looking from the same level, or below, or looking from above.

So a clear definition of what you expect should be established.

Example Box

Common Terminology

© 2024 Printers, Hot Metal Press Ltd. Barnsley, Elsecar Ω