Three questions come before choosing a product: where is the moisture coming from, which material is affected and how extensive is the growth? A single bottle does not answer these questions.
What hydrogen peroxide can do
Hydrogen peroxide is an oxidising ingredient in some mould removers. Such products can temporarily reduce growth but can also harm people, the environment and materials. Biocide treatment is useful only in a few exceptional situations. [1]
Killing is not removing
Even dead mould can cause allergic reactions. Simply treating the growth with chemicals is therefore not enough: it must be removed. [2]
Identify moisture and its cause
Lasting remediation addresses the source of moisture and the affected building material. Repeated spraying or fogging in the room replaces neither investigation nor proper removal. Unclear or hidden damage requires expertise. [3]
When might you clean it yourself?
Germany’s Federal Environment Agency describes small, exclusively superficial growth covering less than about 0.5 m² as a possible case for self-cleaning. The cause and precautions must be clear; seek professionals for larger areas or uncertainty. [4]
The material also matters
Suitable hard surfaces can be cleaned with detergent and water and dried completely. Affected porous materials often cannot be cleaned fully and may need to be replaced. [5]
Protect yourself and others
Gloves, close-fitting protective goggles and suitable respiratory protection are part of preparation. People with mould allergies, chronic respiratory disease or weakened immune systems should not carry out the removal themselves. [6]
Do not experiment with concentrates
Hydrogen peroxide can irritate skin, eyes and airways; concentrated solutions can cause severe injuries. Do not ingest it. This article recommends no dilution or mixing recipes; follow the intended use and protective instructions for the specific product. [7]
Sources
- UBA: Active ingredients against mould
- EPA: Why killing alone is not enough
- UBA: Mould guide, April 2024
- UBA: Frequently asked questions about mould
- EPA: Materials and cleanup
- CDC: Protection during mould removal
- ATSDR: Hydrogen peroxide risks
Editorially revised: 29 October 2026. General guidance for households; not an assessment of a specific building defect.
