There it is again. That smell.
You walk through the front door of a rental property — or you're a landlord doing an inspection — and before you've even taken your coat off, something in the air makes you wrinkle your nose. It's musty. Damp. A little bit old. And it refuses to leave no matter how many windows you open.
A musty smell in rented properties is one of the most common complaints we hear from both tenants and landlords across Somerset, Bath, and Bristol. It's also one of the most misunderstood. People reach for an air freshener, mask the problem for a week, and then wonder why it's back.
This guide is going to help you do better than that. We're going to help you find out where the smell is actually coming from, understand how serious it is, and figure out the most effective way to get rid of it for good.
Not all musty smells are the same, and they don't all come from the same place. Before you can fix the problem, you need to find it.
The most serious source of musty odour in any property — rental or otherwise — is structural dampness. This includes rising damp from the ground, penetrating damp through walls or roofs, and condensation damp caused by poor ventilation.
Signs to look for:
In Somerset particularly, many of the older stone and Victorian terraced properties were built in an era before modern damp-proofing. If you're renting or managing a property that's more than 50 years old, structural damp is a real possibility and should be assessed by a qualified surveyor.
Carpets are remarkable at holding onto moisture and the bacteria, mould spores, and odour compounds that come with it. A carpet that was once wet — from a flood, a leak, a cleaning job that didn't fully dry, or even just years of damp footwear being walked across it — can harbour odour deep within its pile and underlay long after it appears dry to the eye.
Older rental carpets are particularly prone to this. They may have absorbed years of moisture, pet accidents, food spills, and general grime. Surface vacuuming and over-the-counter sprays simply cannot reach the contamination that lives in the backing and underlay.
Sofas, armchairs, curtains, and other soft furnishings work in exactly the same way as carpets. If a rental property comes furnished, the upholstery may be carrying odours from previous tenants. Fabric absorbs airborne moisture, pet dander, smoke, and bacteria over time, creating that characteristic stale, musty smell that no amount of cushion-fluffing can fix.
Mould is a different beast. Where musty smells from damp carpets or walls tend to be vague and pervasive, mould odour is sharper — often described as earthy, rotten, or almost medicinal. It's also more urgent from a health perspective.
Mould thrives in poorly ventilated spaces: behind furniture pushed against cold external walls, inside wardrobes in north-facing rooms, under bath panels, and in basement areas. If you can smell mould but can't immediately see it, check these hidden areas carefully.
This is where most DIY attempts fall short, and it's important to understand it.
A surface smell sits in the top layer of a carpet or fabric. It might be caused by a recent spill, tracked-in mud, or general everyday use. A good vacuum and a quality dry deodoriser can often address these effectively.
Deep-seated contamination is a different matter entirely. When moisture, bacteria, or organic material has penetrated through the pile and into the underlay, backing, or even the subfloor beneath, the smell isn't sitting on the surface — it's embedded. You can spray the top of a carpet until it's soaking and you won't touch the contamination underneath. Worse, adding more moisture without proper extraction can actually feed the bacteria causing the smell.
The test is simple: if the smell returns within a few days of surface treatment, or if it's stronger when the room is warm, you're dealing with deep contamination. This is the point at which DIY approaches run out of road.
We're genuinely fans of people taking care of their homes, so let's be honest about what DIY can and can't do.
What works reasonably well:
What doesn't work as well as the marketing suggests:
When DIY is genuinely not enough:
Professional carpet and upholstery cleaning isn't just a stronger version of DIY — it's a fundamentally different process.
Professional equipment operates at extraction power levels that consumer machines simply cannot match. This means that not only can cleaning solutions penetrate deep into the pile and backing of a carpet, but they can be thoroughly extracted along with the contamination they've lifted. The result is a carpet that dries faster, smells better, and stays better for longer.
At Sheen Services, we've been doing this for over 35 years across Somerset, Bath, and Bristol. We've seen what happens when odour problems go untreated in rental properties — the smell becomes part of the fabric of the building, new tenants complain from day one, and the cost of addressing it compounds over time.
We're WOOLSAFE-approved operators, which means we have specific, manufacturer-endorsed expertise in cleaning wool carpets and soft furnishings. This matters in rental properties because wool carpets are common in older homes, and they require a very different approach to synthetics. The wrong chemical or temperature can cause irreversible damage — shrinkage, browning, or pile distortion. We also hold Gold Membership with the NCCA (National Carpet Cleaners Association), which means we work to a professional standard that has been independently verified.
Let's lift the lid on the process, because understanding it helps explain why it works so much better than the alternatives.
Hot Water Extraction (HWE) — sometimes called steam cleaning, though the water isn't actually steam — is the method used for most carpet odour removal jobs. A pre-treatment solution is applied to break down contaminants at the fibre level. Hot water is then injected under pressure into the pile and immediately extracted along with the loosened soil, bacteria, and odour compounds. Done correctly, this process removes contamination from deep within the carpet structure, not just the surface.
For odour removal specifically, such as pet urine or persistent damp smells, an enzyme-based or oxidising treatment is applied after the main clean. These solutions target the organic compounds responsible for the smell at a molecular level — they don't mask, they neutralise. We use Chemspec Kill Odor Plus for severe odour cases, which has proven particularly effective in rental turnaround situations.
For wool carpets, we use cool water extraction (below 25°C) to prevent shrinkage, along with pH-neutral solutions that won't disturb the fibre structure. Our WOOLSAFE certification covers this specifically.
Upholstery cleaning follows similar principles, adapted for the different fabric types and constructions involved. Whether it's a suite of sofas left by a previous tenant or curtains that have spent years absorbing a damp environment, we extract the contamination rather than simply pushing it around.
We back all our work with a 100% satisfaction guarantee. If a spot or stain returns within 10 days of cleaning, we come back and re-clean it at no extra cost. In a rental context, that kind of assurance matters.
If you're a landlord in Somerset or the surrounding areas, musty smells in rental properties represent a very real risk to your rental income, your reviews, and your ability to attract quality tenants.
Build odour management into your maintenance schedule. Carpets and upholstery in a rental property work harder than in a privately owned home — they see more footfall, more wear, and often less attention. An annual professional clean between tenancies is good practice; in high-turnover properties, it may be necessary more frequently.
Take end-of-tenancy cleaning seriously. An air freshener plugged in by a departing tenant isn't a clean. If the next tenant walks in and immediately notices a smell, the tenancy starts badly before it's even begun. Professional end-of-tenancy carpet and upholstery cleaning is one of the most cost-effective investments a landlord can make.
Document the condition of carpets and soft furnishings at the start of each tenancy. Photographs and written notes at check-in make it far easier to assess what constitutes fair wear and tear at the end. If significant odour contamination has been caused by a tenant — a pet accident that was never reported, for instance — having a clear record of the original condition is invaluable.
Address structural damp separately. Professional cleaning can remove odours that have been absorbed into carpets and upholstery as a result of damp, but if the damp itself hasn't been treated, the smell will return. If you suspect structural damp, get a surveyor involved before investing in cleaning.
We work regularly with estate agents across Somerset and provide end-of-tenancy cleaning services with quick turnaround times. If you need a property cleaned and ready for new tenants, we understand the commercial pressures you're working with.
If you're a renter dealing with a musty smell in a rented property, there are practical steps you can take — and some important things to get on record.
Report it promptly and in writing. If you moved into a property that smelled musty, or if a smell has developed during your tenancy, notify your landlord or letting agent in writing as soon as possible. Email is fine. This creates a record of when the issue was raised and protects you from being held responsible for damage that pre-dated your tenancy.
Photograph and document anything visible. If you can see damp patches, mould, or staining, photograph it with a timestamp. Do the same if odour seems to be coming from a specific area of carpet or wall.
Improve ventilation where you can. This won't fix deep contamination, but it will help manage surface smells and reduce the conditions that allow mould to thrive. Open windows regularly, use extractor fans when cooking and bathing, and try not to push furniture directly against cold external walls.
Understand your rights. If the smell is caused by structural damp that the landlord is responsible for maintaining, you have a right to request that it's addressed. In England and Wales, landlords have legal obligations under the Homes (Fitness for Human Habitation) Act 2018, and persistent damp or mould that affects habitability may fall within this.
Ask about the cleaning history. If your carpets are clearly old and the smell has been there since you moved in, it's entirely reasonable to ask your landlord whether a professional clean was carried out at the end of the previous tenancy.
Somerset is a beautiful county, but there's no getting around the fact that it's wet. The levels, the hills, the proximity to the Bristol Channel — this is a landscape that sees significant rainfall, high humidity, and cool temperatures for much of the year. That has direct implications for the properties here.
Older stone-built and Victorian terraced properties — common throughout Wells, Glastonbury, Shepton Mallet, Bath, and many of the smaller Somerset towns — were built before cavity walls and modern damp-proofing became standard. They're often solid-walled, which means moisture from outside and from ground level can migrate through the fabric of the building. Combined with the Somerset climate, this creates conditions where carpets, soft furnishings, and even the air itself can take on that distinctive musty quality.
This doesn't mean these properties can't be fresh and clean — they absolutely can. But it does mean they often need more regular attention than a modern new-build would, and that professional cleaning is a more regular necessity than an occasional luxury.
We've been working in these properties for over 35 years. We understand the challenges that Somerset's building stock and climate present, and we've developed the methods and the expertise to address them effectively.
Whether you're a tenant who's been putting up with a smell since moving day, or a landlord who wants to present a fresh, clean property to new tenants, we'd love to help.
Sheen Services has been the trusted choice for professional carpet and upholstery cleaning across Somerset, Bath, Bristol, and surrounding areas since 1988. As NCCA Gold Members and WOOLSAFE-approved operators, we bring a level of expertise and care to every job that most cleaning companies simply can't match.
We offer a free, no-obligation in-person quote — so you'll know exactly what we recommend and why before you commit to anything.
Get in touch with the Sheen Services team today and let's sort that smell once and for all.