The honest answer: when a mattress needs replacing
| Situation | What it means |
|---|---|
| The mould is in the mattress, not just on the cover | usually a matter of replacement, because it may not be possible to remove mould completely from inside a porous material |
| The mattress has been soaked | after a thorough soaking a mattress is almost impossible to dry before mould starts to grow |
| The smell stays even after cleaning | the mattress needs replacing |
| A baby, a small child, an elderly person or someone with a respiratory condition sleeps on the mattress | the Health Inspectorate (Veselības inspekcija) lists these groups as particularly sensitive; if in doubt, ask a doctor |
| There is mould on the wall or floor too | the problem is in the room; the mattress is only one of the consequences |
North Carolina State University material makes one more important point: if the inside of a mattress is not completely dry, mould comes back even after treatment. So a surface fix does not help in the long term.
Why mould appears in a mattress
Mould needs moisture. The Health Inspectorate says that relative air humidity above 80% in a room means a high risk of mould. Moisture can reach a mattress from several directions: from the air in the room, from a spilled liquid, from cleaning that is too wet or from where the mattress is placed.
- The room: according to LSM, one in five buildings in Latvia has damp problems.
- Liquid: foam is sensitive to moisture, and water can stay in the core.
- Too much moisture during cleaning: excess moisture can raise the risk of mould.
- Placement: a coconut fibre mattress on the floor can build up moisture.
Before you buy a new mattress, find the cause. Otherwise the new mattress will end up in the same conditions.
What to do now
- If possible, do not sleep on it. Especially if it is a child's mattress or the person sleeping on it has a respiratory or immune system condition.
- Measure the air humidity. Use a hygrometer to find out the humidity in the bedroom. The Health Inspectorate gives 40–60% as the comfort range, and up to 70% is cited as acceptable in a damp climate.
- Look over the room. Check the wall behind the bed, the corners and the base. If mould covers more than about 9 m² or is hidden in the building structure, the Health Inspectorate recommends professional help.
- Air the room. Open the bedroom window every morning for at least 15 minutes and, if possible, dry laundry outdoors.
- Do not douse the mattress. Do not pour water or any other liquid on the mattress to clean off the mould. That adds exactly what mould needs.
What cleaning cannot do and what it can
We do not guarantee that cleaning will eliminate mould, and we do not use such words. Cleaning is not disinfection and it is not a health measure. If you can see mould, there is usually no point in ordering cleaning.
But not every mark is mould. An old water or urine stain, a mark on the cover or a dirty patch can look similar. Send a photo: a specialist will tell you whether it is a job for mattress cleaning or whether it is more honest to replace the mattress.
For stains the price is from €30 for a single mattress and from €45 for a double (one side), second side +50%. The minimum order is €45: if the total is lower, you pay €45. Travel is included in Riga and up to about 15 km outside Riga; further out it is from €10. For other stains: stains on a mattress.
How to protect the next mattress
- Keep the air humidity within the comfort range. The US Environmental Protection Agency recommends below 60%, ideally 30–50%.
- Air the bedroom every morning.
- Blot spilled liquid straight away with towels; do not rub or soak it.
- If the mattress is on the floor, check that the manufacturer allows it.
- Wash a removable cover only as the label says.
The WHO stresses that the main way to avoid health effects is to eliminate damp and mould growth.
Humidity limits and the 9 m² guideline: Health Inspectorate; 60% and 30–50%: US EPA. Sources checked 07.11.2026.
Sources
- Porous materials with mould may have to be thrown away; mould may be hard or impossible to remove completely; humidity below 60%, ideally 30–50% checked 7 November 2026
- After soaking, a mattress is almost impossible to dry before mould starts to grow; if the smell does not go, throw it away; if the inside is not dry, mould comes back checked 7 November 2026
- Sensitive groups; above 80% high mould risk; comfort humidity 40–60%, up to 70%; the 9 m² limit; ventilation for at least 15 minutes checked 7 November 2026
- The main thing is to eliminate damp and mould growth checked 7 November 2026
- One in five buildings in Latvia has damp problems (31.05.2025) checked 7 November 2026
- Foam is sensitive to moisture; latex without direct sun or heat checked 7 November 2026
- Excess moisture can raise the risk of mould checked 7 November 2026
- A coconut fibre mattress on the floor can build up moisture checked 7 November 2026
- Measuring humidity with a hygrometer checked 7 November 2026
- Spilled liquid is soaked up with towels checked 7 November 2026