High humidity levels in a house will lead to condensation and mould which in a short time will lead to damp living conditions. Damp living conditions could give rise to your tenant making a complaint to the local council which may result in a visit by an Environmental Health Officer who will have to conduct a Housing Health and Safety Rating System inspection (HHSRS). If your tenants are in anyway vulnerable it is highly likely that an order will be made for you to reduce the humidity.
The vast majority of complaints we receive from tenants about mould and damp living conditions actually results from high humidity. Generally high ‘in house’ humidity levels are caused by how the property is occupied rather than the property its self. But try explaining that one to the tenants. Tenants who live at home for longer periods and in particular those with new born or young children will produce more moisture adding to humidity levels. Some tenants style of cooking results in increased humidity. You can ask tenants not to dry clothes on radiators and use a particular type of tumble dryer but you cannot control them 24/7. Tenants who are being careful not to waste heating energy may not open windows (restricting ventilation). Tenants will often have heating going on and off during the time they are home and away; this combined with high humidity will increase levels of condensation and mould.
If a property has high humidity it is impossible to stop condensation forming on cold surfaces such as windows, walls and sills adjacent to the window, cold outside walls and parts of the house where warm air may not easily get to or air movement is severely restricted (behind and often inside wardrobes). If condensation is cleaned up daily it will lessen the amount of mould. But can you
imagine your tenants drying the windows on a daily basis and would you if you were renting the property?
Belvoir Lettings one of the leading letting agents in Coventry managing close to 1000 properties advises landlords with properties suffering from high humidity levels to install equipment that changes the humid air in the house with dry air known as Positive Input Ventilation (PIV).
One of the leading installers of PIV equipment is Environment and is recommended by Belvoir Lettings the National Landlord Association plus many Residential Social Landlords (Housing Associations).
Our advice is invest in equipment that will reduce humidity levels that stops mould forming rather than continually demand tenants change how they live, or demand they dry up condensation. It will mean you will not have to redecorate so often so in the medium term it will save you money. Note the expense installing equipment is tax allowable.
