Spring in London is glorious — until pollen counts climb, eyes start streaming, and a third of your office can't concentrate. With around 16 million people in the UK affected by hay fever, the workplace has become one of the most important battlegrounds for managing seasonal allergies. For facility and office managers across London and the South East, a thoughtful cleaning and air-quality strategy can make the difference between a productive team and one quietly suffering through May and June.
This guide explains how allergens build up inside commercial buildings, what the latest UK research says about workplace impact, and the practical steps you can take — many of them low-cost — to reduce allergen exposure in your office this hay fever season.
Why hay fever is a workplace issue, not just a personal one
Hay fever is often dismissed as a minor seasonal nuisance, but the productivity data tells a different story. Research compiled by Allergy UK suggests that 46% of sufferers struggle with concentration and 35% report that symptoms reduce their productivity at work. With around a quarter of UK adults affected, that translates into a significant drag on output across any office of more than a handful of people.
London offices face a particular challenge. Although urban areas tend to have lower raw pollen counts than the countryside, traffic-related air pollution interacts with pollen grains in ways that make symptoms worse, not better. Diesel particulates can rupture pollen and release allergenic proteins more efficiently into the airways, which is one reason hay fever symptoms are often reported as more severe in cities than the surrounding shires.
Add in the building-related allergens that accumulate year-round — dust mites in upholstery, mould spores in damp corners, and pet dander brought in on clothing — and the modern office becomes an allergen reservoir. The good news is that almost every contributor is something a well-run cleaning programme can address.
Understanding the UK pollen calendar
Effective allergen management starts with knowing what you're dealing with and when. The UK pollen season runs roughly from late March to September, but it isn't one continuous wave. It's three overlapping seasons:
Tree pollen: late March to mid-May
Birch is the main offender for many sufferers, followed by oak, plane and hazel. Plane trees are everywhere in London squares and along the embankments, which means central London tends to see a sharp tree-pollen spike in April and early May.
Grass pollen: mid-May to July
This is the big one. Around 95% of hay fever sufferers react to grass pollen, and the May–July peak is when symptoms tend to be most severe. Counts are highest on warm, dry, breezy days.
Weed pollen: late June to September
Nettle, dock and mugwort are the main UK culprits. The numbers affected are smaller than for grass, but for those affected the season can stretch well into early autumn.
The Met Office publishes a five-day pollen forecast for each region, and London and the South East almost always share the same risk profile. Building this forecast into your weekly facilities huddle is one of the simplest things you can do — it lets you ramp cleaning up on high-count days and communicate proactively with staff.
How allergens get into your building
Pollen is sticky. It clings to coats, hair, bags and shoes, and a single commuter walking from London Bridge to their desk can carry tens of thousands of grains with them. Once inside, those grains settle on hard floors, work into carpet pile, drift onto desks and monitors, and get pulled through air-handling systems.
The other major indoor allergens accumulate more quietly:
- Dust mites thrive in soft furnishings, upholstered chairs, fabric partitions and carpets. Their droppings are a major year-round trigger.
- Mould spores develop wherever there's condensation or unresolved damp — around tea points, under sinks, in poorly ventilated meeting rooms and behind older window frames.
- Pet dander hitchhikes in on clothing from any colleague with a dog or cat at home.
- Cleaning chemical residues can themselves trigger respiratory symptoms in sensitive staff, particularly fragranced products.
A practical allergen-reduction plan for London offices
You don't need a specialist contractor or a six-figure refit to make a meaningful difference. The plan below works for the vast majority of small and mid-sized commercial properties across London and the South East.
1. Upgrade your daily cleaning approach during pollen season
From late March onwards, ask your commercial cleaning provider to shift from dry dusting to damp microfibre wiping on all hard surfaces. Dry dusting simply lifts pollen and other particles into the air, where they recirculate for hours. Damp microfibre captures and removes them.
Other small adjustments that pay off quickly:
- Increase the frequency of horizontal-surface cleaning (desks, monitors, window sills, picture rails) from twice weekly to daily during peak weeks.
- Wipe down door handles, lift buttons and reception counters more often — these are pollen entry points as well as touch points.
- Ensure cleaners use HEPA-filter vacuums rather than older bag-style machines, which can blow fine particles straight back out of the exhaust.
- Switch to low-fragrance, low-VOC cleaning chemicals where possible. Many ecolabel-certified products are formulated to reduce respiratory irritation.
2. Tackle carpets and soft furnishings properly
Vacuuming, even with a HEPA machine, only removes surface debris. Twice a year — typically once before pollen season and once at the end of the summer — carpets, fabric chairs and acoustic panels should be deep cleaned. Hot-water extraction or low-moisture encapsulation systems remove embedded pollen, dust mite debris and skin cells that ordinary vacuuming leaves behind.
If your London office has heavy traffic carpeted areas — reception, breakout zones, meeting room corridors — consider bringing a deep clean forward to early April. Mithraic's professional carpet cleaning service is built around exactly this kind of seasonal reset.
3. Control entry points
The single most cost-effective allergen-reduction measure is a proper barrier matting system at every external door. A good barrier system needs at least four to five metres of length to capture the majority of debris from a typical walk-on. Many London offices are working with one small mat at the entrance, which simply isn't enough.
Other entry-point measures worth considering:
- Provide a coat and bag area away from the main desk space, so staff aren't shaking pollen off coats over their workstations.
- Keep windows closed on high pollen-count mornings, especially in offices fronting busy roads or large green spaces.
- If your building has revolving doors, make sure the seals and brushes are intact — they're an underrated air quality control.
4. Look after your ventilation system
Air-handling units are the lungs of any commercial building, and poorly maintained ones recirculate everything they pull in. The Workplace (Health, Safety and Welfare) Regulations 1992 already require employers to ensure effective ventilation, but allergen control demands a step beyond minimum compliance.
Ask your facilities team or maintenance contractor to:
- Inspect and replace filters at the manufacturer's recommended interval — and consider upgrading to a higher MERV-rated filter if your system supports it.
- Schedule duct cleaning every three to five years, or sooner in older buildings.
- Check for and clear any signs of microbial growth in cooling coils, drip trays and humidifiers.
- Verify that fresh-air intakes are not positioned next to obvious pollen or pollution sources.
5. Address damp and humidity early
Mould is the allergen most likely to be missed in routine inspections because it grows out of sight. Walk your building once a fortnight in spring and check tea points, toilet ceilings, basement storage, window reveals and any space behind heavy furniture for signs of damp or discolouration. Resolve the underlying cause, not just the visible symptom.
Aim to keep relative humidity in occupied spaces between 40% and 60%. Above 60%, dust mites and mould both thrive; below 40%, eyes and airways dry out and become more reactive to whatever allergens are present.
6. Communicate with your team
Even the best cleaning programme works better when staff know what's going on. A simple internal note at the start of pollen season — explaining what the office is doing and what colleagues can do themselves — costs nothing and demonstrates that the business takes wellbeing seriously. Practical suggestions you can share include keeping desk areas clear of clutter, leaving outdoor coats at the door, and using the building's quieter zones on bad-symptom days.
Building a seasonal cleaning specification
If you're refreshing your cleaning contract or having a conversation with your current provider, push for a specification that explicitly recognises the pollen season. A good seasonal supplement should include:
- Daily damp-wipe of all horizontal surfaces from 1 April to 31 July.
- HEPA-vacuuming of all carpeted areas at least every working day during peak weeks.
- Weekly wipe-down of vents, grilles and high-level surfaces.
- One mid-season deep clean of upholstered furniture and high-traffic carpets.
- Filter checks on local air purifiers, where fitted.
Most reputable London providers will be happy to add this as a clear deliverable rather than a vague "as required" line. If yours isn't, that may be a sign it's worth reviewing your options.
The bottom line for facility managers
A clean office isn't just a tidy office. During hay fever season, it's the difference between a workforce that can concentrate and one that can't.
The interventions in this guide are deliberately practical: damp wiping rather than dry dusting, deep-cleaned carpets, longer barrier matting, well-maintained ventilation, proactive damp checks and clear staff communication. None of them require a major capital project. Together, they materially reduce the indoor allergen load and the productivity hit that comes with it.
If you'd like an independent walk-through of your London or South East office to identify the quickest wins for this hay fever season, the Mithraic team is happy to help. Get in touch via our contact page for a no-obligation conversation about your space.
