Bulk Buying 20mm Flat Glazing Packers: Which Thicknesses Do Installers Use Most?

When installers, glazing firms, and trade buyers order 20mm flat glazing packers in bulk, the key question is usually not whether they need them, but which thicknesses they should keep most heavily in stock.

Our FP20 flat glazing packers are supplied in packs of 1000 and are available in 1 mm, 2 mm, 3 mm, and 5 mm thicknesses. Because the range is compact, bulk buying decisions tend to be simpler than with wider product ranges. Instead of spreading stock across many sizes, most buyers are choosing between fine-adjustment stock, standard everyday stock, and heavier-support stock.

What Makes the FP20 Range Different

Our FP20 range is designed for 20 mm glazing systems and uses a shorter thickness ladder than some of our other flat glazing packer ranges. We offer:

• 1 mm
• 2 mm
• 3 mm
• 5 mm

That means the range focuses on the most practical support categories rather than every possible step in between. The packers are made from polypropylene, measure 20 mm × 100 mm, and are suitable for uPVC, aluminium, and timber frames, including windows, doors, conservatories, and curtain walling.

The Thickness Installers Usually Use Most Often

For most everyday installations, the thickness installers are most likely to use most often is usually:

• 3 mm

That is because we position 3 mm as the standard all-round size for:

• typical window and door glazing
• standard levelling and support
• general-purpose installations

In a compact range like FP20, 3 mm naturally becomes the centre of gravity for bulk buying because it is the size that covers the broadest share of routine work.

Why 3mm FP20 Packers Are a Core Bulk Stock Line

Our 3 mm FP20 packers are the most obvious everyday stock size because they fit standard glazing work without being too light or too specialist. For many installers, this is the packer thickness that gets used again and again on normal jobs.

That makes 3 mm one of the strongest candidates for the main bulk-purchase line when buyers want a dependable day-to-day stock size.

Why 5mm FP20 Packers Matter More Than the Narrower Range Might Suggest

Even though the FP20 range is compact, 5 mm plays an important role because it is the heavier-support option in the line. We recommend 5 mm for:

• larger gaps
• heavier sealed units
• structural support and base packing

This means 5 mm is not a niche afterthought. For installers who regularly work on jobs needing stronger support, it is often the second most important thickness to keep in bulk after 3 mm.

Where 1mm and 2mm Fit Into Bulk Buying

Our 1 mm and 2 mm FP20 packers are usually more useful as support stock than as the main bulk lines.

We recommend 1 mm for:

• final alignment adjustments
• removing very small gaps
• fine-tuning after main packing

We recommend 2 mm for:

• slightly uneven surfaces
• minor spacing corrections
• light levelling under glazing units

These are very useful thicknesses to have available, but they are generally used to refine or finish an installation rather than carry the main support load on most jobs.

A Different Buying Pattern from FP24 and FP28

Because FP20 has only four thicknesses, the bulk-buying pattern is usually more concentrated than with ranges like FP24 or FP28.

Instead of spreading demand across 3 mm, 4 mm, and 5 mm, FP20 buyers are usually building stock around:

• 3 mm for routine everyday work
• 5 mm for heavier support work
• 1 mm and 2 mm for finishing and light correction

That makes FP20 a very practical range for trade buyers who want a simpler and more focused stock profile.

A Practical Bulk-Buying Approach for FP20

A sensible way to bulk buy FP20 glazing packers is:

• keep 3 mm as the main everyday stock size
• keep 5 mm as the heavy-support stock size
• keep 1 mm and 2 mm available for fine correction and finishing work

For many trade buyers, that means the heaviest stock focus will fall on 3 mm, followed by 5 mm, with 1 mm and 2 mm acting as supporting sizes rather than the main volume lines. This is a practical inference based on the intended uses of each FP20 thickness.

Why Many Installers Still Keep All Four Sizes Available

Even if 3 mm and 5 mm are likely to do most of the work, there is still a strong case for keeping the full FP20 range in stock.

That is because different installations call for different levels of correction. Some jobs only need a slight finishing adjustment, while others need standard support or stronger base packing. Keeping 1 mm, 2 mm, 3 mm, and 5 mm available gives installers more flexibility and reduces the temptation to use the wrong size simply because it is the only one on hand.

Why FP20 Works Well for Bulk Trade Orders

Our FP20 glazing packers are a practical bulk-buying product because they combine:

• a 20 mm × 100 mm format
• four focused thickness options
• polypropylene construction
• suitability for multiple frame materials
• packs of 1000
• bulk trade pricing
• UK-held stock

For trade customers, that makes FP20 easy to standardise, easy to reorder, and easy to issue across installation teams.

Final Thoughts

If you are bulk buying 20mm flat glazing packers, the thickness installers are most likely to use most often is usually 3 mm, because it covers the broadest range of standard everyday glazing work. 5 mm is the next important thickness for larger gaps and heavier support requirements, while 1 mm and 2 mm are best kept available for finer adjustments and light levelling.

For many trade buyers, the most practical approach is to build FP20 stock around 3 mm and 5 mm, while still keeping 1 mm and 2 mm available to complete the range and handle finishing work.