You moved in a few weeks ago. The flat is bright and freshly painted, with new floors and windows that close perfectly. Yet you wake with a stuffy nose, your eyes sting in the evening, and the headaches seem to ease on the days you spend elsewhere. You start to wonder whether the home itself is the problem.
It is confusing because so much changes at once with a move: the air, your routines, often your sleep and your stress. Indoor air is invisible, what you can smell is not always what matters, and the advice online ranges from air purifiers to full laboratory analyses.
This guide walks you through it: why new homes often have more in the air at first, what the usual suspects do, from VOCs and formaldehyde to damp, radon and faulty appliances, then what is worth measuring, how to lower emissions and when symptoms need a doctor.
Start with the building itself: why a new or renovated home often has more in its air at first, and what symptoms tied to a building usually look like.
New homes often have more in the air at first#
Paints, glues and sealants release the most vapours while they dry and harden, in the first days and weeks after building or renovation,1 and formaldehyde is often very high in the first months.2 An airtight home keeps them in unless it is aired.
The Federal Office of Public Health notes that people who move in too early often complain about odours and poor air, and advises waiting long enough before moving into a new or freshly renovated home.1 Regular airing matters most in new or renovated buildings with airtight walls and windows, especially in the first weeks.3
Average formaldehyde levels in new buildings have fallen considerably since the 1980s, but they are still often very high in the first months.2 New buildings also hold extra water from materials that are still drying, one more reason to air more after construction work.4
- Since we moved in I’m always stuffy
- My eyes sting in the new flat
- The headaches ease when I’m away
- That new furniture smell
- Everything is so airtight
- The paint smell won’t go
Symptoms tied to a building fade when you leave#
Sick building syndrome describes irritated eyes, nose, airways or skin, often with headache, tiredness, dizziness or poor concentration, that appear in a building and fade after leaving it. Its causes range from poor ventilation and irritating emissions to damp, noise and stress.5
Most research comes from workplaces, but homes are affected too.5 In offices, higher ventilation rates, up to about 25 litres per second per person, are linked with fewer such symptoms, and in Nordic homes better air exchange went with fewer allergic symptoms in children.6
Building-related illness, in one sentence
A clinically defined condition with a clear link to a building, such as an allergy to dust mites or moulds, legionellosis, or ‘humidifier lung’ from a poorly maintained humidifier. It is different from sick building syndrome.[7]
Several of those causes have names you will soon meet when you read about indoor air.
Understand your new home and your health better
Nine short questions, and one of our experts reviews your case personally, then goes through it with you on a free call.
Chemicals from materials, moisture that is still drying out, a radioactive gas from the ground and a faulty appliance: four things worth understanding, each in its own way.
VOCs and formaldehyde mostly irritate#
Typical low-level mixtures of volatile organic compounds can irritate mucous membranes and bring headaches, tiredness and malaise, though their long-term effects are not well studied.8 Formaldehyde mainly irritates the eyes, nose and throat.2
VOCs, in one sentence
Volatile organic compounds: substances that pass easily into the air from products such as paints, glues, sealants and floor and wall coverings.[1]
Formaldehyde is taken up by the lining of the nose and throat within minutes, so its effects stay where the air touches: burning eyes, a prickling nose or throat, a runny or blocked nose, and with lasting irritation, headache, fatigue and malaise. The symptoms fade quickly once levels fall. The federal health office recommends not exceeding 0.1 ppm, or 125 µg/m³, in homes.2
Common sources are particle board, MDF and plywood, some parquet varnishes with a built-in hardener, and thick textured plasters, which can release it for weeks or months. Tobacco smoke is a major indoor source: three cigarettes are enough to exceed the guideline value.2 Because the long-term effects of low-level chemical mixtures are not yet well studied, the federal health office advises keeping homes as unpolluted as possible.8
New buildings dry out, and walls can darken#
Materials that are still drying release extra moisture in new buildings and after major renovations, so these need more airing for some weeks. Grey-black marks in the first heating season are often not mould at all.4
Fogging, sometimes called ‘black magic dust’, shows up as dusty or greasy grey-black deposits, often where warm air rises along walls, mainly in new or renovated homes during the first heating period. It is made of semi-volatile compounds from coverings, paints, glues and furnishings, combined with fine particles such as candle soot. The deposits are visible damage without danger to health, and more airing is advised.4
Real mould still needs attention wherever it appears. Our guide to damp and mould at home explains the signs, what you can clean yourself and what to report.
Radon is worth checking, and only a measurement shows it#
Radon, a natural radioactive gas from the ground, is the main cause of lung cancer after smoking and causes 200 to 300 deaths a year in Switzerland.9 Only a measurement shows how much is in your home.
Its decay products lodge in lung tissue and irradiate it, and years or decades can pass before cancer appears.9 Switzerland is particularly affected because of its geology.10 Radon enters through leaks in the parts of a building that touch the ground. New windows and doors that make a home airtight have the biggest effect on its level, so a check is advised after such work, while homes with controlled mechanical ventilation generally have lower levels.11
Since 2018, Switzerland has applied a reference level of 300 Bq/m³ as an annual average in rooms where people spend several hours a day.12 Pooled European data found no safe threshold: lung cancer risk rose by about 16% for every 100 Bq/m³ of long-term radon, and the absolute risk was about 25 times higher in smokers.13
Flues, stoves and gas cookers need checking#
Chimneys and heaters with leaky flues can endanger health, which is why they need regular checks.3 Carbon monoxide gives no visible warning, and its headache, dizziness and nausea are easily mistaken for a virus.14
Gas cookers release nitrogen oxides and carbon monoxide, so air while and after cooking. If a fireplace, stove, oven or gas water heater lowers the oxygen in a room, a fresh air supply has to be planned.3
Carbon monoxide is colourless and odourless, and because its symptoms are non-specific, the clue is often the setting, such as an unusual or faulty heat source.14 If you suspect it, get everyone into fresh air and call 144. Tox Info Suisse gives free advice on poisoning day and night on 145.15
Most of what affects indoor air is less dramatic, and some of it is easy to measure.
Here is the practical side: what is worth measuring, what you can change from this week, and where to start if you suspect your home.
Measure radon, CO2 and humidity; test chemicals with care#
Three measurements are simple and useful: radon over a heating season, carbon dioxide as a guide to airing, and humidity.1617 Tests for formaldehyde and other chemicals make sense when symptoms clearly follow the building.2
| What | How and when |
|---|---|
| Radon | A dosimeter from an approved service, for at least 90 days between October and March, in at least two regularly used rooms on the lowest lived-in floor; some cantons offer it free.16 The federal radon map shows the probability of exceeding the reference level where you live.18 |
| Carbon dioxide (CO2) | A CO2 meter shows when a room needs air: ideally once it passes 1,000 ppm, at the latest at 1,400 ppm. Values above 2,000 ppm are unacceptable.17 |
| Humidity | A hygrometer: 30% to 50% in the heating season, no more than 40% on very cold days.19 |
| Formaldehyde and VOCs | Worth measuring when your eyes, nose or throat are irritated indoors, it eases after you leave, and the building or furniture is new. Cantonal chemical services advise on how.2 |
| Mould | Not usually measured: no reliable, meaningful method exists.20 |
People cannot sense when a room needs air, which is why a meter or a fixed airing routine helps.17 Hasty do-it-yourself analyses of suspected pollutants, on the other hand, often give results that mean little; an experienced specialist should look at the home first.21
Air more, keep it cool, and let new things air out#
Extra airing in the first weeks, rooms no warmer than about 21 °C with humidity below 50% in winter, new furniture aired out before it moves in, washed textiles and a smoke-free home all lower what you breathe.32
Start with your doctor and a simple record#
The federal health office advises seeing your family doctor first, especially when symptoms are serious or do not clearly match your time at home.21 A short record of what you notice helps both your doctor and anyone who looks at the building.
Worth noting: which symptoms exactly, who in the household has them, whether they worsen at home and ease away, whether they began with an event such as a renovation, any unusual smells, misted windows or stains, and how the home is aired.21
If the cause seems to lie in the building, contact the owner or management quickly and in writing, by registered letter for damp and mould. Where emissions from building materials are suspected, an experienced specialist should visit before anything is measured.21
A few symptoms cannot wait for any measurement. This last part says which, and where our work sits alongside your doctor’s.
Some symptoms cannot wait for a measurement#
Headache, dizziness or nausea around a heating or cooking appliance needs fresh air and help at once.14 Symptoms that persist, worsen or do not clearly follow your time at home belong with your family doctor.21
Carbon monoxide symptoms are easily mistaken for a virus,14 and the federal health office advises seeing your family doctor first when symptoms are serious or do not clearly match your time in the building.21
We look at the whole move, alongside your doctor#
Our work runs alongside medical care, never in place of it. Your doctor looks at the symptoms and specialists at the building, while we work with you on what a move and months of feeling below par can unsettle.
A move changes far more than the air: routines, sleep, commute, meals, often stress. When you feel worse afterwards, the building may be part of it, or only part. This guide does not replace a medical assessment, and neither do we.
What we can do is look at the whole picture with you: sleep, nutrition, movement, stress and digestion, coordinated with your doctor whenever medical care is needed. Talk it through with our care team on a free call. It is a coaching conversation, not a medical consultation.
Quick answers11 questions this guide covers, in short
Why might you feel worse after moving into a new home?
New and renovated homes often have more chemicals in the air at first, as paints, glues and sealants dry and new materials release vapours, and airtight buildings keep them in unless they are aired. Emissions are highest in the first days and weeks, and formaldehyde can stay high for months. Read the section
What is sick building syndrome?
A name for irritated eyes, nose, airways or skin, often with headache, tiredness, dizziness or poor concentration, that appear in a particular building and fade after leaving it. It has several causes, from poor ventilation and irritating emissions to damp, noise and stress. Read the section
What are VOCs and formaldehyde, and what do they do to you?
VOCs, volatile organic compounds, are vapours from products such as paints, glues and coverings; at the low levels typical of homes they can cause irritation, headaches, tiredness and malaise. Formaldehyde irritates the eyes, nose and throat, and the federal guideline value for homes is 0.1 ppm (125 µg/m³). Read the section
Can a brand-new building be damp?
Yes: new buildings and major renovations release extra moisture from materials that are still drying, so they need more airing for some weeks. Grey-black deposits that appear on walls in the first heating season are often not mould but ‘fogging’, a dust of chemical residues. Read the section
Should you worry about radon in a Swiss home?
It is worth checking. Radon is a natural radioactive gas from the ground, the main cause of lung cancer after smoking and responsible for 200 to 300 deaths a year in Switzerland; the reference level for homes is 300 Bq/m³ as an annual average, and only a measurement shows your level. Read the section
Could a gas or wood appliance be making you unwell?
It can, if it is not working properly. Chimneys and heaters with leaky flues can endanger health, and carbon monoxide, which you cannot see or smell, causes headache, dizziness and nausea that are easily mistaken for a virus. Read the section
What is worth measuring in a new home?
Radon, with a recognised dosimeter over at least 90 days in the heating season; carbon dioxide, as a guide to when to air; and humidity. Formaldehyde and other chemicals are worth testing when symptoms clearly follow the building, ideally with a specialist. Read the section
How can you lower emissions in a new home?
Air more in the first weeks, keep rooms no warmer than about 21 °C and humidity below 50% in winter, air out new furniture before it comes into the living rooms, wash new textiles, and keep smoke out of the home. Read the section
Where should you start if you think your home is making you ill?
With your family doctor, to look at the symptoms themselves, and with a simple record of what you feel, who is affected, whether it is worse at home and better away, and any smells or signs of damp. Problems that seem to come from the building go to the owner or management in writing. Read the section
When should you see a doctor about symptoms that seem linked to your home?
At once if headache, dizziness or nausea come on around a gas or wood appliance, or if breathing becomes difficult. See your family doctor soon for symptoms that persist, worsen or do not clearly follow your time at home. Read the section
Where does a functional approach fit if you feel worse since moving?
Alongside medical care, never instead of it. Your doctor looks at the symptoms and specialists at the building; we work with you on the sleep, nutrition, movement, stress and digestion that a move, and months of feeling below par, can unsettle. Read the section
- Federal Office of Public Health (FOPH). Emissions provenant des matériaux. Bern: FOPH; 25 November 2024, accessed 26 October 2026. Link
- Federal Office of Public Health (FOPH). Formaldéhyde à l’intérieur des locaux: informations et conseils au consommateur. Bern: FOPH; May 2010. Link
- Federal Office of Public Health (FOPH). Aération et chauffage appropriés. Bern: FOPH; accessed 26 October 2026. Link
- Federal Office of Public Health (FOPH), with ASLOCA, the Swiss Homeowners’ Association and SVIT. Attention aux moisissures: guide sur les problèmes d’humidité et de moisissures dans les locaux d’habitation. Bern: FOPH; 2009, reissued August 2023 (publication 311.310.f). Link
- Federal Office of Public Health (FOPH). Le syndrome des bâtiments malsains. Bern: FOPH; 13 March 2025, accessed 26 October 2026. Link
- Sundell J, Levin H, Nazaroff WW, et al. Ventilation rates and health: multidisciplinary review of the scientific literature. Indoor Air. 2011;21(3):191-204. PMID : 21204989. Link
- Federal Office of Public Health (FOPH). Les maladies liées au bâtiment. Bern: FOPH; accessed 26 October 2026. Link
- Federal Office of Public Health (FOPH). Polluants de l’air ambiant: effets sur la santé. Bern: FOPH; accessed 26 October 2026. Link
- Federal Office of Public Health (FOPH). Le radon provoque le cancer du poumon. Bern: FOPH; accessed 26 October 2026. Link
- Federal Office of Public Health (FOPH). Radon. Bern: FOPH; accessed 26 October 2026. Link
- Federal Office of Public Health (FOPH). Radon et mesures énergétiques dans les bâtiments. Bern: FOPH; accessed 26 October 2026. Link
- Federal Office of Public Health (FOPH). Dispositions légales concernant le radon. Bern: FOPH; accessed 26 October 2026. Link
- Darby S, Hill D, Auvinen A, et al. Radon in homes and risk of lung cancer: collaborative analysis of individual data from 13 European case-control studies. BMJ. 2005;330(7485):223. PMID : 15613366. Link
- Ng PC, Long B, Koyfman A. Clinical chameleons: an emergency medicine focused review of carbon monoxide poisoning. Intern Emerg Med. 2018;13(2):223-229. PMID : 29435715. Link
- Tox Info Suisse. Notruf 145 (24-hour poisons emergency line). Zurich: Tox Info Suisse; accessed 26 October 2026. Link
- Federal Office of Public Health (FOPH). Mesurer la concentration en radon. Bern: FOPH; accessed 26 October 2026. Link
- Federal Office of Public Health (FOPH). Bien aérer: fiche d’information. Bern: FOPH; 31 August 2022. Link
- Federal Office of Public Health (FOPH). Carte du radon en Suisse. Bern: FOPH; accessed 26 October 2026. Link
- Federal Office of Public Health (FOPH). Moisissures dans les habitations: une brochure pour les habitants, les locataires et les bailleurs. Bern: FOPH; January 2021 (publication 311.311.f). Link
- Federal Office of Public Health (FOPH). Problèmes d’humidité et moisissures. Bern: FOPH; accessed 26 October 2026. Link
- Federal Office of Public Health (FOPH). Marche à suivre en cas de troubles liés à une habitation. Bern: FOPH; 13 March 2025, accessed 26 October 2026. Link
Articles published by FunctionAlps are educational and written within ASCA and EMR scope. They do not replace personalised clinical advice. When findings warrant medical evaluation, we coordinate with a referring physician.