Start with the conditions, not blame.
Mould indicates that a surface has stayed damp enough for growth. The reason may involve water entry, a leak, ventilation, cold surfaces, heating, occupancy or several factors together. A fair investigation records conditions and property defects before deciding on the cause.
Keep a record
Take dated photographs, note the rooms, timing, weather, heating and ventilation, and keep copies of messages and replies.
Deal with urgent risks
Arrange the appropriate help for active leaks or urgent electrical and structural concerns. Avoid disturbing extensive mould without suitable precautions.
Investigate
Check the property fabric and ventilation together. A surface clean may be part of remediation, but it does not remove the moisture source.
Make the record easy to follow.
Write down when you first noticed the mould, where it spread, what you told the landlord or agent, and what happened next. Keep copies of emails, messages, photographs, appointment offers and repair notes in date order.
Be specific about access. If a visit is proposed, reply with reasonable availability or explain why an appointment cannot go ahead. Note missed visits, temporary cleaning, leaks and any change after work. A clear chronology helps the tenant, landlord, contractor and any council team discuss the same sequence.
Record building evidence
A survey can document visible mould, moisture patterns, humidity, ventilation, access limitations and defects that are visible or safely testable.
Every hidden cause
One visit may not reveal concealed leaks, inaccessible shared areas, seasonal changes or the full drying behaviour of a wall.
Other decisions
A survey is not a medical assessment, legal ruling, structural design or emergency response. It should say when another professional or further monitoring is needed.
Check the guidance for your type of tenancy.
Responsibilities and time limits depend on the type of tenancy, location and circumstances. Use current government and local-council guidance for legal information.
Know when a survey is not the first call.
Mould and damp can be distressing and may affect some people more seriously. Seek appropriate medical advice for health concerns; a property survey cannot diagnose or treat illness. For immediate danger, use the relevant emergency service or regulated professional for the problem involved.
Active flooding, exposed or wet electrics, suspected gas problems, fire risk or signs of structural instability need urgent attention. Keep people away from the danger and follow emergency or contractor advice before arranging a routine damp inspection.