Manufacturer · Fashion & Home Accessories
For mattress and upholstery covers, spiral zips in size No. 5 or No. 8 are most commonly used, sold by the metre with non-locking sliders. The zip usually runs along three or four sides of the cover, so lengths vary and are large – making zipped-by-the-metre more practical than ready-made zips. For heavy sofa and seat covers, a larger No. 8 or No. 10 zip is preferred.
Why spiral zips are suitable for mattresses and upholstery
Covers for mattresses, furniture cushions and seats are removable for washing or replacement, and the zip must withstand stretching when fitting the cover over dense foam. Spiral zips are flexible and can bend around corners without breaking. The tape is easy to sew into the piping or side strip, and the zip can be cut to any length.
- Flexibility at corners – the zip goes around the cover without jamming.
- Long lengths – all sizes can be cut from one zipped-by-the-metre roll.
- Quiet and smooth operation – important for furniture and bedding products.
- Colour matching – the zip blends into the side strip of the cover.
Which zip for mattress and upholstery – size and type
| Product | Size | Type | Sliders |
|---|---|---|---|
| Mattress cover (upholstered mattress) | No. 5 or No. 8 | Zipped by the metre, on three or four sides | One or two, non-locking |
| Protector and topper | No. 3 or No. 5 | Zipped by the metre or ready-made | One, non-locking |
| Sofa cushion cover | No. 5 | Closed end, ready-made or zipped by the metre | One |
| Seat and backrest cover | No. 5 or No. 8 | Zipped by the metre | One or two |
| Poufs, beanbags, garden cushions | No. 8 or No. 10 | Zipped by the metre | One, sometimes locking |
For decorative cushions where the zip should not be visible, invisible zips are also used – see invisible zips.
How to calculate the zip length for a mattress
- Decide how many sides the zip will open. For three sides, the cover opens like a lid; for four sides, the top part is fully removable.
- Add the lengths of the sides. For example, for a 160 × 200 cm mattress with a zip on three sides: 200 + 160 + 200 = 560 cm.
- Add allowance for corners and ends – a few centimetres on each side depending on seam construction.
- Calculate total metres for the series by multiplying by the number of covers per size and adding allowance for defects.
- Determine the number of sliders – one or two per cover.
If you work with different mattress sizes, zipped-by-the-metre allows covering all sizes from one roll instead of stocking separate ready-made zips. More details about this format are in the spiral zips category.
Sliders: one or two
For zips on three or four sides, two sliders are more convenient: the cover can be opened from one corner without the slider having to travel the full perimeter. Sliders are placed so they meet at a corner or mid-side where they do not interfere with sitting or lying. Locking is not necessary – the zip is sewn into a strip that does not stretch vertically.
For children's mattresses, poufs and public spaces, sliders without handles or with removable handles are sometimes preferred – this prevents easy opening of the cover.
Sewing the zip into the cover
- Sew the zip into the side strip or between the strip and the top panel, leaving space from the coil.
- Make small notches in the tape at corners to bend without creasing.
- Hide the zip under a narrow fabric flap if the cover is visible – for example, on a sofa.
- Seal the polyester tape ends with a hot knife when cutting from the roll.
- Close the zip before washing the cover.
Materials and washing
Mattress and furniture covers are often washed at higher temperatures than clothing. Polyester coils and tape withstand repeated washing well, but sliders and their coatings must also be suitable. If covers will be industrially washed – for example in hotels or hospitals – mention this in your enquiry to offer the right option. For outdoor furniture, choose moisture-resistant sliders.
Common mistakes
- Too fine a size for a cover that is hard to fit – the coil separates under tension.
- Only one slider for a zip on four sides – opening becomes inconvenient.
- Ready-made zips in standard lengths that do not match the mattress size.
- Slider placed in the middle of the lying surface – felt during use.
- No allowance at corners – the cover stretches and the zip works under strain.
For furniture and accessories with heavier covers, you can also consider moulded zips, which are stiffer and withstand heavy loads.
Zips for mattresses and upholstery by Polkom
Polkom is a manufacturer and wholesaler of accessories for fashion, furniture, footwear and bags from Sofia with over 30 years of experience. We supply spiral zips by the metre in various sizes and colours, sliders and stoppers for mattress, upholstery and home textile manufacturers, as well as samples before production. Minimum order quantities depend on the item. Send a request for quote with your product dimensions, sizes and colours.
