Reliable Wedge Packers for Precise Glazing and Spacing Needs

Polypropylene wedge packers for precise, tool-free adjustment when levelling windows, doors and frames. Available in 24mm, 28mm, 30mm and 32mm widths. Interlock in pairs for stepless shimming.

What are wedge packers?

Wedge packers are tapered plastic shims used in pairs for infinitely adjustable shimming. You slide two wedges towards each other from opposite sides until the combined thickness fills the gap — creating a solid, parallel-sided packing block at exactly the right thickness. Made from tough polypropylene that won't compress under sustained load. Available in 24mm, 28mm, 30mm and 32mm widths.

When to use wedge packers vs flat packers

Wedge packers are ideal when the gap is uneven or unknown — you adjust thickness on site without stacking. Use them for frame-to-subframe packing, levelling frames in out-of-square openings, and anywhere the gap varies across the frame width. Flat packers are faster for standard, predictable gaps like toe-and-heel glazing and are colour-coded by thickness for easy identification. Most professional installers carry both types in the van.
Trade Tip

Installation tip: Always use wedge packers in opposing pairs, inserted from opposite sides of the frame. A single wedge creates an uneven bearing point that distributes load unevenly across the frame — this stresses the sill and can lead to distortion over time.

Frequently Asked Questions

How do wedge packers work?

Place two wedge packers together with tapered ends facing opposite directions. Slide them towards each other until the combined thickness fills the gap. The interlocking surfaces grip so the wedges don't slip once positioned. This gives infinitely adjustable packing from minimum to maximum thickness.

Are wedge packers better than flat packers?

Neither is universally better — they serve different purposes. Wedge packers excel when gaps are uneven or unknown. Flat packers are faster for standard predictable gaps and are colour-coded for easy identification. Most installers carry both.

Can I use wedge packers for frame fitting?

Yes — frame fitting is one of the most common uses. Position wedge pairs between the window frame and the structural opening to level and plumb the frame before fixing. The stepless adjustment makes it easy to get a perfectly level frame even in an out-of-square opening.