Asthma is set to increase due to improved efficiency in house design noii's/Flickr

The number of people who suffer from asthma is set to double in the UK by 2050, because of changes in the design and construction of new homes. Increased energy efficiency means houses are now more airtight, trapping pollen which can cause asthma.

Worst affected by the problem will be those who spend most time indoors, including the young, the elderly and young mums. Opening windows may not be enough to alleviate the problem, says air equality expert Professor Hazim Awbi.

Stuart Braggs
Apprentice star Stuart Baggs died from an asthma attack at the age of 27 (BBC)

"Poor indoor air quality is connected with a range of undesirable health effects, such as allergic and asthma symptoms, lung cancer, chronic obstructive pulmonary disease, airborne respiratory infections and cardiovascular disease," says Awbi.

"With the expected increase in airtightness for UK dwellings, it is anticipated that indoor air quality will generally become poorer, resulting in an increase in the number of cases of health symptoms related to poorer indoor environment quality."

Professor Peter Howarth from Southampton University has called for greater awareness of "Toxic Home Syndrome" and believes a "Healthy Home Mark" on new homes could reduce the risk.

"Toxic Home Syndrome occurs when individuals and families are exposed to a potent mix of airborne pollutants within the home arising from poor ventilation, causing respiratory and skin diseases to occur more frequently," said Professor Howarth. "I would like to see a 'Healthy Home Mark' on new homes to confirm that they have mechanical ventilation systems with effective heat exchange installed – to help reduce the health risks for future generations."

Currently, 5.4 million people in the UK suffer from asthma, which kills an average three people a day. Former Apprentice star Stuart Baggs died from an attack this year. Andrew Proctor from Asthma UK said: "We know that indoor exposure to allergens can be a real problem for some people with asthma, but it is difficult to avoid them."