28mm Glazing Packers: Bulk Buyer’s Guide for Window Installers

For window installers, 28mm glazing packers are one of the most useful flat packer sizes to keep in regular stock. They provide a wider support surface than narrower packers, making them a practical choice for 28mm glazing systems, sealed units, windows, doors, curtain walling, and conservatories.

If you install windows regularly, buying 28mm glazing packers in bulk is usually far more practical than buying small packs when each job comes in. Packs of 1000 help keep your van or warehouse stocked, reduce site delays, and make sure the correct thickness is available when you need it.

Why 28mm Glazing Packers Are Popular with Installers

28mm glazing packers are used where a stable, flat support surface is needed beneath or around a sealed glass unit. They help installers level, support, and align the unit so it sits correctly within the frame.

They are especially useful for:

• 28mm glazing systems
• uPVC window installations
• aluminium frames
• timber frames
• sealed glass units
• door glazing
• curtain walling
• conservatories
• larger or heavier glazing jobs

For installers who work across different types of windows and doors, 28mm flat glazing packers are a strong all-round stock item.

Why Bulk Buying Makes Sense

A single installation can use multiple glazing packers. Across several jobs, the numbers add up quickly.

Buying in bulk helps installers:

• reduce the risk of running out on site
• keep the most-used thicknesses available
• avoid expensive last-minute purchases
• standardise van stock
• reduce downtime
• buy in a more organised way
• keep repeat jobs moving smoothly

For trade buyers, packs of 1000 are not just about quantity. They are about keeping work efficient.

What 28mm Glazing Packers Are Used For

28mm flat glazing packers are used to support and position sealed units during installation. Their job is to provide consistent spacing and help prevent unnecessary pressure, movement, or poor alignment.

Common uses include:

• supporting sealed units
• levelling glass within the frame
• helping maintain even load distribution
• aligning window and door glazing
• reducing the risk of rattling
• helping prevent frame distortion
• assisting with consistent installation practice

The key point for installers is that the packer should support the unit properly, not simply fill a gap.

Available Thicknesses for 28mm Glazing Packers

Our 28mm flat glazing packers are available in:

• 1mm
• 2mm
• 3mm
• 4mm
• 5mm
• 6mm

This gives installers a complete working range, from fine adjustment through to heavier support and larger spacing requirements.

Which 28mm Thicknesses Should You Buy First?

For most trade buyers, the best starting point is the middle of the range.

The most useful 28mm thicknesses to stock in bulk are usually:

• 3mm
• 4mm
• 5mm

These three thicknesses cover a large share of everyday glazing work.

The smaller thicknesses, 1mm and 2mm, are useful for fine adjustment.

The 6mm thickness is useful for larger gaps, base packing, and heavier support points.

1mm 28mm Glazing Packers

Use 1mm 28mm glazing packers for fine adjustment and final levelling.

They are useful when the unit is already close to the correct position and only a small correction is needed.

Typical uses include:

• final alignment adjustments
• removing small gaps
• fine-tuning after the main packers are already in place
• minor corrections where a thicker packer would be too much

For bulk buyers, 1mm is useful to keep available, but it is usually not the main high-volume thickness.

2mm 28mm Glazing Packers

Use 2mm 28mm glazing packers for light levelling and small spacing corrections.

They are useful when 1mm is not enough, but the job still only needs a modest adjustment.

Typical uses include:

• slightly uneven surfaces
• minor frame inconsistencies
• light levelling under glazing units
• small adjustment points during installation

For installers, 2mm is a useful support thickness to carry alongside larger core sizes.

3mm 28mm Glazing Packers

Use 3mm 28mm glazing packers for standard everyday packing.

This is one of the most useful thicknesses for regular window installation work because it suits a wide range of routine support and levelling tasks.

Typical uses include:

• general window installations
• standard levelling work
• typical glazing support
• everyday sealed unit positioning

For many window installers, 3mm should be one of the first 28mm thicknesses to buy in bulk.

4mm 28mm Glazing Packers

Use 4mm 28mm glazing packers where a standard 3mm packer does not provide enough correction.

This thickness is useful for moderate gaps, uneven openings, and slightly heavier sections.

Typical uses include:

• medium adjustments
• supporting heavier sections
• aligning slightly misaligned frames
• dealing with noticeable but manageable unevenness

For trade buyers, 4mm is a strong core stock size because it sits between standard support and heavier correction.

5mm 28mm Glazing Packers

Use 5mm 28mm glazing packers where the job needs stronger support or a more noticeable lift.

This is a very useful thickness for heavier sealed units and larger gaps.

Typical uses include:

• larger gaps
• heavier sealed units
• structural levelling requirements
• stronger support points

For window installers buying in quantity, 5mm is one of the most important 28mm packer thicknesses to keep in stock.

6mm 28mm Glazing Packers

Use 6mm 28mm glazing packers when significant correction or support is needed.

This is the heaviest thickness in the 28mm range and is useful where the job requires greater spacing or stronger base support.

Typical uses include:

• large gaps
• uneven openings
• high load-bearing points
• base packing under frames
• heavier installation conditions

For bulk buyers, 6mm is worth keeping available, especially if you regularly work on larger windows, doors, or more demanding glazing jobs.

Recommended Bulk Stock for 28mm Glazing Packers

A practical bulk stock setup for 28mm glazing packers would be:

• higher stock of 3mm
• higher stock of 4mm
• higher stock of 5mm
• smaller stock of 1mm and 2mm
• smaller but important stock of 6mm

This gives installers the right balance between everyday stock and specialist support sizes.

Best 28mm Thicknesses for Everyday Window Installation

For everyday window installation, the most useful 28mm thicknesses are usually:

• 3mm for standard support
• 4mm for moderate correction
• 5mm for stronger support

These thicknesses should form the core of your 28mm bulk order if you are buying for regular installation work.

Best 28mm Thicknesses for Heavier Units

For heavier sealed units, larger windows, or jobs needing more support, the key thicknesses are:

• 5mm
• 6mm

These give more support than lighter packers and are useful when the installation requires stronger packing points.

Best 28mm Thicknesses for Fine Adjustment

For fine adjustment and finishing work, the best thicknesses are:

• 1mm
• 2mm

These are useful when the unit is already close to the correct position and only small correction is needed.

They may not move as quickly as the core sizes, but they are important for clean, accurate fitting.

Why Window Installers Should Not Stock Only One Thickness

Some installers try to simplify their stock by buying only one thickness. That can work on repetitive jobs, but it is usually limiting.

If the packer is too thin, the unit may not be properly supported.

If the packer is too thick, it may create unnecessary pressure or make the fit less accurate.

Keeping a range of thicknesses means installers can choose the correct packer for the job instead of forcing every job to work with the same size.

Why 28mm Packers Are Useful for Van Stock

For installers working from a van, 28mm glazing packers are worth keeping in regular stock because they cover a broad range of jobs.

A sensible van stock setup could include:

• 28mm 3mm packers for standard support
• 28mm 4mm packers for moderate correction
• 28mm 5mm packers for heavier support
• 28mm 1mm and 2mm packers for fine adjustment
• 28mm 6mm packers for larger gaps and base packing

This gives installers enough flexibility to handle most 28mm glazing situations without leaving site to find another size.

Why 28mm Packers Are Useful for Installation Companies

For glazing companies with multiple installers, bulk buying 28mm packers helps standardise stock across vans and teams.

Instead of every installer carrying different products, the company can issue the same core sizes to each van.

This helps with:

• stock control
• easier reordering
• consistent installation practice
• less improvisation
• fewer emergency purchases
• better planning for larger jobs

For busy installation firms, consistent stock can make a real difference to daily efficiency.

How Many Packs Should You Buy?

The right quantity depends on how many jobs you complete each month.

For a self-employed installer, a starting setup may be:

• 1 pack of 1000 in 3mm
• 1 pack of 1000 in 5mm
• smaller stock of other thicknesses

For a small installation team, a better setup may be:

• multiple packs of 3mm, 4mm, and 5mm
• one pack each of 1mm, 2mm, and 6mm

For larger companies, stock should be based on regular monthly usage and the number of vans that need to be supplied.

When to Buy 28mm Instead of 20mm or 24mm Packers

Choose 28mm glazing packers when the job needs a wider support surface or when working specifically with 28mm glazing systems.

As a simple guide:

• choose 20mm for narrower or more compact support points
• choose 24mm for general-purpose glazing work
• choose 28mm for wider systems and stronger support requirements

Many trade buyers keep all three sizes available, but 28mm is especially useful where support area and load distribution matter.

Bulk Buying Mistakes to Avoid

When buying 28mm glazing packers in bulk, avoid these common mistakes:

• buying only one thickness
• ignoring fine adjustment sizes
• failing to stock heavier support sizes
• buying too many slow-moving sizes before testing usage
• using 28mm packers where a narrower packer would be more suitable
• relying on improvised shims instead of proper plastic glazing packers

The best approach is to build stock around the most-used sizes, then adjust future orders based on what your team actually uses.

Final Thoughts

28mm glazing packers are a strong bulk-buying choice for window installers who need reliable support, levelling, and spacing for sealed units. They are especially useful for 28mm glazing systems, wider support points, heavier units, and regular trade installation work.

For most window installers, the best bulk stock strategy is to prioritise:

• 3mm for standard everyday support
• 4mm for moderate correction
• 5mm for stronger support

Then keep:

• 1mm and 2mm for fine adjustment
• 6mm for larger gaps, base packing, and higher load-bearing points

Explore our 28mm flat glazing packers in packs of 1000 and choose the thicknesses that best match your installation work.