Wool is everywhere in Cumbria. This is sheep country, and a good wool carpet has been the sensible choice in Lakeland farmhouses, cottages and holiday lets for generations - warm underfoot, hard-wearing and naturally good-looking. So when someone asks how to clean their carpet, my first question back is nearly always the same: do you know what it is actually made of?

It matters more than people expect. Wool and synthetic carpets want almost opposite treatment, and while a synthetic will forgive a lot, wool can be harmed by the wrong product in one go - sometimes the first time you reach for a supermarket spray. Here is how to tell what you have, and how to look after each kind without wrecking it.

First, work out what you have got

Start with the paperwork, not a test. The original invoice, the manufacturer's spec sheet or the warranty booklet will usually state the fibre content - pure wool, a blend such as 80% wool with 20% nylon, or a synthetic like polypropylene. Wool may also carry the Woolmark logo on its label or paperwork, which certifies the wool content. Kept an offcut from the fitting? Check the label on its back. Nothing at all? Ask whoever supplied or fitted it, as a good carpet shop usually has the record. And worth knowing: many quality British wool carpets are an 80/20 blend (the 20% nylon adds durability), so for cleaning, treat anything mostly wool as wool.

If you have nothing to go on, your hands give a clue: wool feels soft, dense and springy and bounces back when you press into it, and being a short, crimped natural fibre it often sheds little flecks of fluff when newish (completely normal). The old burn test works too: wool smoulders rather than blazes, smells like burning hair and leaves a soft ash you can crush to powder, while synthetics melt, shrink from the heat and harden into a bead that will not crush. But it destroys fibres and is a fire risk, so only try it on a tiny tuft over a sink - and honestly, if in doubt, the label beats setting light to your carpet.

Wool: the premium fibre, and why it is fussy

Wool is the quiet luxury of the carpet world, and deservedly so: naturally resilient, soft, soil-resistant and naturally flame-resistant. It is also, chemically, the most delicate carpet you can own, which catches people out precisely because it is so tough in every other way.

The reason is simple: wool is a protein fibre, made of keratin, the same family of material as your own hair. So it reacts badly to the things that are hard on hair - strong alkaline chemistry, bleach and harsh heat - giving you yellowing, browning, colour bleed and brittle, weakened fibres, sometimes after a single wrong application rather than gradually.

The number that matters is pH. Wool is happiest with products in a roughly neutral range, about pH 5.5 to 8.5; stray much beyond about pH 8, into strongly alkaline territory, and you start to risk damage. The catch is that plenty of ordinary spot cleaners are strongly alkaline - some supermarket spot removers are pH 10 or more - and you cannot tell from the bottle. Chlorine bleach is an obvious no. Less obviously, many "oxy" or oxygen stain removers are a gamble on wool too, because at the wrong strength the active oxygen can lighten or alter its colour unless the product is specifically tested to be gentle enough.

That is why wool should be cleaned with WoolSafe-approved products: WoolSafe is an independent body that tests cleaners and certifies the ones proven safe on wool, so instead of gambling on whether the bottle under the sink is too harsh, you use something tested on the fibre. Every PureFell clean uses WoolSafe-approved, plant-based products, which is exactly the care a wool carpet needs.

Myth-buster: "Wool is hard-wearing, so it can take a strong cleaner." It can't. Wool is brilliantly tough underfoot but chemically fragile - the strength that lets it last for decades has nothing to do with how it copes with a harsh, alkaline or "oxy" product, which can mark it in one go.

Synthetic carpets: more forgiving, but each has quirks

Most carpet sold today is synthetic, and the great advantage is that synthetics are far more tolerant of cleaning than wool - a wider pH range, warmer water, and much less chance of lasting harm from an everyday spill. But "synthetic" covers three quite different fibres, each with its own character.

Nylon is the workhorse and the toughest of the three: strong, springy and very resistant to abrasion, crushing and wear, so it holds up in busy hallways and on stairs and responds well to a professional clean. Its weak spot is staining - untreated nylon marks more readily than the others, and the factory stain-resist finish most nylon carpets carry wears off over the years, so do not assume an older one is as stain-proof as it once was.

Polyester (sometimes labelled PET) is loved for being soft and for holding rich, bright colours, and it shrugs off water-based stains well, though oily, greasy marks cling to it more stubbornly. Its bigger catch is resilience: it is not crush-resistant, so it flattens and "uglies out" in traffic lanes faster than wool or nylon. A clean revives the look, but once the pile has genuinely crushed, no clean fully restores it.

Polypropylene (also called olefin) is the budget all-rounder, common in loop pile and in holiday lets. It is nearly waterproof and exceptionally colourfast, so it shrugs off water-based stains and even strong sunlight - but it has two quirks. First, it loves oil: greasy soil clings to it so stubbornly that a polypropylene carpet can still look grubby in the traffic areas after a clean. Second, it is the least resilient of the lot and crushes easily, which is why it is so often made into hard-wearing loop pile rather than deep cut pile. And because it barely absorbs water, a DIY machine can leave it sitting wet on top.

If you are not certain which synthetic you have, keep any spot cleaning gentle and check your manufacturer's guidance before reaching for anything stronger.

Everyday care: much the same for both

The day-to-day routine is broadly the same whatever the fibre, and most of it you do yourself.

  • Vacuum regularly. It is the single most valuable thing you can do for any carpet, lifting the dry, gritty soil that would otherwise grind into the pile and wear it down. Aim for at least weekly, more on stairs and in hallways - and on loop-pile wool or polypropylene, use suction rather than an aggressive rotating brush, which can fuzz the loops.
  • Treat spills fast and gently. The golden rules hold for every fibre: blot, do not rub; work from the outside in; cool water, never hot; and never bleach. The difference is the margin for error - on a synthetic you have a little room, on wool almost none - so keep wool to blotting and cool water and leave anything tricky to a WoolSafe-approved cleaner. Our five-minute spill guide has the step-by-step for wine, mud and coffee.
  • Deep clean periodically. Vacuuming cannot lift the oily, bonded soil that builds up deep in the pile; that is the job of a professional hot-water extraction clean, about every 12 to 18 months for most homes and sooner with pets or children (our guide to how often to clean your carpets covers what shortens the gap). Fast drying matters too: wool can brown if left over-wet, and low-absorbency polypropylene is easily over-soaked, so we set up drying fans when a quicker turnaround helps.
You can do this yourselfWorth a WoolSafe-approved pro
Vacuum weekly (suction only on loops)The periodic deep clean, whatever the fibre
Blot fresh spills with cool water, outside inAnything on wool beyond a simple fresh spill
A gentle, fibre-appropriate spot treatment on syntheticOily, set-in marks on polypropylene or polyester
Move furniture now and then so wear spreadsOld or stubborn stains and tired traffic lanes

The short version

Before you clean a carpet, find out what it is: check the original paperwork or an offcut label, and look for the Woolmark on wool. Wool is a protein fibre and chemically delicate, so keep it away from strongly alkaline cleaners (much above pH 8), chlorine bleach, "oxy" products, harsh heat and over-wetting, any of which can mark it in a single application - and use WoolSafe-approved products. Synthetics are more forgiving: nylon is tough and cleans up well but marks more once its stain-resist finish wears; polyester is soft but flattens in traffic; polypropylene shrugs off water but grabs oily soil and crushes. For both, vacuum weekly, blot spills with cool water (never hot, never bleach), and deep clean every 12 to 18 months with good drying.

If you are not sure what your carpet is made of, or you would simply rather not risk the wrong product on a wool carpet you love, that is exactly what we are here for. As a WoolSafe-approved cleaner using plant-based products, we match the method to your fibre and give you an honest view of what is achievable before we start. You can see how we work on our carpet cleaning page, or, if you are local, how we cover Keswick and the surrounding fells. Whenever you are ready, get a free, no-obligation quote - no pressure, just straight advice for your carpets. Every job is backed by our Fresh-Finish Guarantee, so if you feel we have fallen short, we come back and re-clean it.

PureFell is an eco-friendly carpet and upholstery cleaning service based in Penrith and covering the Lake District. Every clean is plant-based and WoolSafe-approved, carried out by the same DBS-checked, fully insured owner-operator from the first quote to the final walkthrough.

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