Letting Agents

Letting Agents

Mould Problems in Rented Properties

Many letting agents will get a call from a tenant complaining of bad condensation and mould growth on the ceiling and walls. The tenant may find that their clothes and belongings have been damage by mould growth, and their health is been affected. The letting agent may have rented the property for many years with only small amounts of mould growth and will now feel that it is the tenants fault and they are to blame for the damage caused to the property. The tenant maybe slow to notify the landlord or letting agent about the mould growth as they do not see the damage caused to the property and sometimes, they will just move out instead of letting you know. But the cost of maybe finding a new tenant, cleaning the mould growth and repainting the property can be expensive with the chance of having to do this all again the next year. You can also find damage to the windowsills and bad mould growth on blinds, beds and wardrobes. The RTB will usually take the tenants side in any dispute of damage to the tenant’s property or health unless the landlord can prove the property meets the current building regulation for ventilation.

Contact Us Today For Advice View Recommended Products

Who is to Blame?

We find that with most surveys on rented properties the blame is usually somewhere close to 50/50. There is always some problem with the ventilation system especially with apartments. But also, it is how the tenant lives in the property and sometimes their genuine lack of knowledge about the need to ventilate their home. Other problems that lead to mould growth in rented properties can be the following:

  • (1) Overcrowding of small properties with people or belongings.
  • (2) Poor heating of the property by the tenant to save money on fuel.
  • (3) Switching off bathroom fans with the isolator switch, because of the noise of the fan and to save money on heating. Also in the bathroom of apartments where all the walls are internal, there is usually little mould growth so the tenant does not see the need for ventilation.
  • (4) Constant drying of clothes in the property during the day when there is nobody in to open a window.
  • (5) Cooking and not using the cooker extractor fan.
  • (6) Many tenants do not know about the trickle vents in the windows or if there are wall vents these are usually closed.
  • (7) Poor cross ventilation under the doors to allow air movement.
  • (8) Many bathroom fans are under powered and very poorly ducted. Together with no maintenance of the fan, the extraction level in many cases is next to zero.
  • (9) All domestic properties should achieve a constant half an air change per hour which is usually done with wall vents or trickle vents. In most properties there are not enough vents but then again if the vents are closed this will make no difference.
  • (10) There may be a structural problem leading to leaks or penetrating damp.
  • (11) There can be insulation problems or thermal bridging even if the property is relatively new or been retrofitted with insulation.
  • (12) There may be problems with the heating system which the tenant has not brought to the letting agents notice.
Contact Us Today For Advice View Recommended Products

The Solution

We do a full thermal imaging and damp survey with a written report with thermal images. We will also include pictures of the mould problem as we are aware that many landlords do not visit there property.


We highlight any problems with the property and also issues about the tenant behavior that is causing condensation and mould growth problems.



We then propose a ventilation solution and costing that will meet the requirements of the building regulations for that property. As it is a rented property our solutions will be tamper proof but also silent so the tenant does not know the system is running. With all tenanted properties we recommend constant running systems that give a low rate of ventilation 24 hours a day but can also react to any moisture increase in the property. We explain to the tenant how the system works and we leave information in a visible place so the tenant is aware about the importance of ventilation. To make our system tamper proof we install key operated isolator switches and most of our units have hour counters. As every property is different there is no one fits all solution, but these are some of the units we use

Contact Us Today For Advice View Recommended Products

Recommended Products For Rented Houses

Need help with condensation, mould or damp problems?

Share by: