Mixed Packer Sets vs Single-Size Packers: Which Should You Buy?

Why Choosing the Right Type of Packers Matters

Whether you’re installing uPVC windows, aligning door frames, or levelling kitchen units, the packers you choose have a direct impact on speed, accuracy, and the overall quality of the installation.
Installers usually decide between buying mixed packer sets (multiple sizes in one box) or single-size packs (bulk quantities of one specific thickness).

Both have advantages — but the right choice depends on how you work and the types of installations you handle.

This guide explains the differences and helps you choose the best option for your toolkit.

What Are Mixed Packer Sets?

Mixed sets contain a range of packer thicknesses in one box. A typical set includes:

• 1 mm
• 2 mm
• 3 mm
• 4 mm
• 5 mm
• 6 mm
• Sometimes 8–10 mm

They are colour-coded according to industry standards.

Benefits of Mixed Packer Sets

1. Versatility for Any Job

Mixed packs give you every thickness you might need.
This is ideal for installers who work on:

• Different window systems
• Door frames
• Timber installations
• General construction tasks

2. Perfect for On-Site Adjustments

When you don’t know what you’ll encounter on-site, mixed sets allow you to adapt quickly.
For example:

• If the cavity is uneven
• If the frame is not perfectly plumb
• If the sash requires fine alignment
• If drainage gaps vary

Mixed packs cover all scenarios.

3. Ideal for DIY or Occasional Installers

Homeowners or occasional fitters benefit from having multiple sizes without buying full boxes of each thickness.

4. Saves Time Searching for Sizes

Colour-coding lets you instantly grab the thickness you need.

Downsides of Mixed Sets

• You may run out of popular sizes (3 mm, 4 mm, 5 mm) faster than others.
• Not ideal if you constantly use the same thickness in high volume.
• More expensive per-pack compared to bulk single-size boxes.

Mixed sets are best for flexibility, not volume work.

What Are Single-Size Packers?

Single-size packers come in boxes containing only one thickness — for example:

• 3 mm only
• 5 mm only
• 6 mm only

These packs are used heavily by installers who frequently work with specific systems that require predictable spacing.

Benefits of Single-Size Packers

1. Most Cost-Effective for Professionals

Buying a box of 100–1,000 packers of the same thickness is cheaper per unit.
Installers who go through lots of the same size save money in the long run.

2. Ideal for High-Volume or Repeat Work

If you install the same type of windows daily (e.g., uPVC casements), you’ll use certain thicknesses more than others.

Common high-usage sizes include:

• 3 mm
• 4 mm
• 5 mm

Buying them in bulk prevents running out mid-job.

3. Perfect for Toe-and-Heel Work

Toe-and-heeling often uses:

• 3 mm
• 4 mm
• 5 mm

Having bulk boxes of these makes installation faster.

4. Great for Manufacturing and Workshop Environments

Fabricators often use a predictable packer thickness for assembly.
Single-size boxes streamline production.

Downsides of Single-Size Packs

• Less flexibility
• You may need several boxes to cover all thicknesses
• Not ideal for DIY or first-time installers

Single-size packs are best for professionals doing repeat work.

Which Should You Choose?

Here’s the quick answer depending on your situation:

Choose Mixed Packer Sets if:

• You want versatility
• You work on different types of frames weekly
• You need all sizes available on-site
• You are doing DIY or occasional installations
• You want a compact box for general purpose use

Ideal for:
General installers, multi-system fitting, DIY, first-time buyers.

Choose Single-Size Packers if:

• You know you need a specific thickness often
• You do high-volume or repetitive work
• You regularly toe-and-heel uPVC sashes
• You install frames in similar openings each day
• You want the lowest cost per packer

Ideal for:
Professional installers, workshops, fabricators, bulk users.

Best Strategy for Professional Installers

Most professionals use both:

• 1–2 mixed sets for flexibility
• Bulk boxes of their most-used sizes (usually 3 mm, 4 mm, 5 mm)

This gives you the speed of bulk packs plus the adaptability of a mixed kit.

Final Thoughts

Both mixed sets and single-size packs have a place in the glazing industry.
Mixed sets give you flexibility, while single-size packs give you efficiency and cost savings.

For a complete toolkit, consider carrying:

• Mixed Packer Set (for general use)
• Bulk Single-Size Packs (3 mm, 4 mm, 5 mm for everyday glazing work)
• Wedge and bridge packers for specialised adjustments