Drying laundry inside the home could pose health risks, according to a study.
Research carried out by the Mackintosh Environmental Architecture Research Unit (MEARU) at the Glasgow School of Art revealed that laundry habits could also create economic problems.
Could drying clothes this way be causing health problems?
Hanging washing on airers and radiators is common practice and is responsible for one third of moisture in the home.
Experts say these conditions encourage mould spores and dust mites which are known causes of asthma.
Professor Colin Porteous, of MEARU, said: "Because of increased awareness of the energy consumption of tumble dryers many people are choosing to dry clothes passively within their home.
"This results not only in a severe energy penalty, because of increased heating demand, but also a potential health risk due to higher moisture levels.
"Minor changes to the wording of the regulations would have multiple beneficial consequences. Our research gives strong justification for the changes both in terms of health and wellbeing, and associated economic impacts.
"It is our hope that current statutory and advisory standards will be modified to take them on board ensuring a healthy and economically sustainable living environment."
The study also showed that indoor drying also causes environmental and economic problems which house builders should take into account.
The current UK trend for airtight construction and smaller homes contributes towards moisture build-up, it said
The study suggests separate drying spaces should be included in the design whether they be communal or as part of individual properties while a short-term solution would be to improve ventilation.