17/08/2026
🏠 Why Does My Mould Keep Coming Back?
You've cleaned it.
You've sprayed it.
You've painted over it.
And a few weeks or months later... it's back.
The problem is that removing visible mould and solving the reason it's growing are two very different things.
Mould needs moisture to grow. So if it keeps returning, the important question isn't simply:
“How do I get rid of the mould?”
It's:
“Where is the moisture coming from?”
And there isn't always one simple answer.
Recurring mould and condensation can be influenced by a combination of factors, including:
💨 Poor extraction: bathroom or kitchen fans may be fitted but not actually moving enough air.
🪟 Insufficient background ventilation: including missing, blocked or closed trickle vents.
🌡️ Cold surfaces and thermal bridging: certain areas of walls and ceilings can remain significantly colder, increasing the risk of surface condensation.
💧 Leaks or water ingress: moisture may be entering through the building fabric, roof, plumbing or external defects.
🏠 Insulation and building defects: missing or poorly installed insulation can create localised cold spots.
🚿 Moisture generated inside the home: showering, cooking, drying clothes and simply living in a property all introduce moisture into the air.
🔥 Heating patterns: colder rooms and surfaces can increase the likelihood of condensation forming.
And sometimes it's several of these factors working together.
That's why simply spraying mould killer, repainting the wall or automatically assuming a property needs a new damp-proof course may not solve the problem.
Finding the cause comes first.
At homeperform, our damp and moisture investigations look beyond the visible mould.
Depending on the property and the problem, our investigation can include:
✓ Moisture readings
✓ Relative humidity and temperature measurements
✓ Thermal imaging
✓ Ventilation and extraction assessment
✓ Airflow testing
✓ Inspection of the building fabric
✓ Consideration of heating and condensation patterns
✓ Investigation of potential moisture sources
The aim is simple:
Understand what's causing the problem before deciding how to fix it.
Because the right solution might be improving extraction or ventilation, repairing a building defect, addressing a leak, improving insulation or changing how moisture is managed within the home.
And identifying the correct cause could save you from spending thousands of pounds on unnecessary work that doesn't solve the problem.
If you're struggling with mould, condensation or unexplained damp and want to understand what's actually happening in your home, speak to homeperform about an independent damp and moisture survey.