Bed linen buying guide

To help you sleep easy, we take you through the lingo you need to know when shopping for sheets. We also sent five sheets to the lab to see how different thread count sheets perform for durability and pilling (those annoying little balls of fibre caused by wear that can make your sheets feel a bit like sandpaper).

Buying tips

• Go prepared: know the size of your bed and measure your mattress to be doubly sure of the right fit. The depth of mattresses can vary and if yours has a pillow-top, you’ll want to make sure the sheets fit.

• If the sheets aren’t on display at the store, take them out of the pack and see how they feel. Bear in mind that once sheets are washed a few times they’ll soften up.

• Check the stitching on the wide hem of the top sheet and on the pillowcases. Stitches should be small, tight and free of loose ends.

• Check the label for the thread count and the ply of the yarn. If it’s not stated, ask. You can also ask whether the sheet has been tested for pilling and durability, and what the results showed.

• If you want to splash out on some pricey sheets but are unsure if you’re choosing the right ones, buy the pillowcases first and see how you like them.

• Sheets made from natural fibres will breathe better. Cotton is the obvious choice. If you like wrinkle-free sheets, 100 percent sateen cotton sheets are less prone to creases.

Thread count

On the front of the pack, you’ll usually find the sheet’s thread count. It tells you the number of threads (both vertical and horizontal) in a square of fabric. It’s either shown per 10cm² or per square inch.

We found thread count can range from 180 to 1000.

A decent sheet should have a reasonable thread count. But here’s the rub: a higher thread count doesn’t always mean better quality. For example, sheets made with a thinner yarn will have a higher thread count because there will be more threads per 10cm². However, thin yarn may mean the sheet won’t wear as well.

As well as thread count, the quality of the fibre, ply, weight and weave all influence how well your sheets will stand up over time.

Certification ticks

When you’re shopping for sheets, you might spot products with organic or other environmental certifications. What do they tell you?

The Global Organic Textile Standard (GOTS) logo and the Organic Content Standard (OCS) were the main marks we found.

There are two GOTS certifications: GOTS Organic certification requires a product to have at least 95 percent organic fibres, while the GOTS Made with X% organic label requires at least 70 percent.

The OCS also has two logos. The OCS 100 logo means the product has at least 95 percent organic material while OCS Blended only requires a minimum of five percent.

You might find the Better Cotton Initiative (BCI) logo. It signals the manufacturer is using at least 10 percent sustainably sourced cotton, with a plan to use 50 percent within five years.

Some manufacturers also opt for Bluesign or Oeko-Tex certification. These schemes set health and environmental standards relating to chemical use in textile manufacturing.

Jargon buster

• Combed cotton has the short fibre removed, which creates a more regular and less hairy yarn, and therefore a smoother fabric.

• Egyptian cotton doesn’t necessarily come from the banks of the Nile. It may just mean the bed linen is made from long-staple cotton. An Egyptian Cotton “gold seal” on the pack tells you the fibre was grown in Egypt (although the sheets may have been manufactured somewhere else). The logo is the trademark of the Egyptian Ministry of Industry and Foreign Trade and the Alexandria Cotton Exporters’ Association.

• Fabric-finishing is applied to some sheets to reduce pilling and creasing. Generally, this improves the durability of the sheets. Sheets are singed (burning the tiny fuzz from the surface of the fabric) to reduce pilling or may be mercerised with caustic soda (sodium hydroxide) to increase the lustre and strength of the fabric. Mercerising also makes the fabric more receptive to dyes.

• Flannelette sheets are generally made from cotton but are brushed to create a softer and warmer feel.

• Long-staple cotton comes from varieties of the plant that grow long fibres. Percale and Egyptian cotton sheets are typically made from long-staple cotton.

• Percale, or plain weave, means the yarns are closely woven in an over-under pattern (much like lattice on a pie). Percale sheets are more likely to have a lower thread count (200 to 300) and their texture is crisp and cool.

• Sateen sheets (or satin weave) have fewer interlacings to give a smoother and silkier feel than percale. Because the weave is prone to snags, manufacturers may put more threads in to compensate, which makes the sheets stronger, but also heavier and warmer.

Our trial

We sent five sheets to the lab to see how different thread count sheets perform for durability and pilling. Our lab test showed how performance can vary, even when comparing sheets with the same thread count.

The cheapest sheet with the lowest thread count (180) performed the worst for pilling: it was a $19 polyester/cotton BH Brampton House sheet from Spotlight.

A $49 Home Co cotton sheet from Bed Bath & Beyond, also with a 180 thread count, did better.

To test for pilling, the sheet is rubbed against itself 7000 times. After 2000 “rubs”, this sheet showed obvious pilling. However, at 7000 rubs the pills had disappeared (though whether you’d be prepared to put up with the early pilling is another matter).

Bed Bath & Beyond said it tested the Home Co sheet using a different test method, which found it showed “slight pilling” at 1000 rubs.

The sheet in our test with the highest thread count (400) – a Briscoes’ Gracious Living sateen cotton sheet – showed moderate pilling at 7000 rubs. Distributor NZ Merchants said it had tested the sheet to 2000 rubs. Its results were similar to our findings at 2000 cycles.

We got mixed results for the organic cotton $72 Royal Doulton sheet, bought at Briscoes. It passed the pilling test but didn’t perform as well for durability, starting to show wear before any of the others. Caprice NZ, which manufactures Royal Doulton, said its sheets are tested for performance but didn’t provide the results.

Just one product, a percale $49 Solace cotton/polyester sheet, sold at Bed Bath & Beyond, performed consistently well in both our pilling and durability tests. It had a thread count of 250.

About our test

We tested five sheets with a thread count ranging from 180 to 400 for durability and pilling.

Testing was carried out by the New Zealand Wool Testing Authority (NZWTA). Samples were sent to the lab “blind”.

To assess durability, the lab used the Australian standard for abrasion resistance: AS 2001.2.25.1-2006 Methods of test for textiles - Determination of the abrasion resistance of fabrics by the Martindale Method.

Durability was measured by rubbing the textile 20,000 times. While the standard doesn’t set a minimum “pass” mark for bed linen, the NZWTA used 20,000 abrasions as the benchmark.

The pilling test used ISO 12945-2:2000 Determination of fabric propensity to surface fuzzing and to pilling (part 2 modified Martindale method).

In this test, the fabric is rubbed against itself 7000 times and graded on a scale from one to five. A measure of five at 7000 cycles shows no change in fabric, four indicates slight fuzz, and three or below shows moderate to dense pilling.