More people will die in house fires after the smoking ban, claims a new report.
Direct Line Home Insurance and the Fire Protection Association have issued the warning after the insurance company undertook a survey of 2,400 people.
It says smokers and their families will be at greater risk after the ban as more of them are forced to light up at home.
We are estimating that the ban will result in 100 more house fires a year, and some of those are going to be fatal Andrew Lowe, Direct Line's head of home insurance.
Around 100 more house fires - some of which will be fatal - are predicted every year following the July 1 ban.
Cigarettes are already the number one cause of accidental fatal fires in the home, and are currently responsible for 60 house fires a week.
Direct Line claims 11% of smokers surveyed said they will be forced to smoke more at home - which will mean an extra 16 million cigarettes will be lit indoors every week.
In England and Wales, 70 per cent of smokers currently light up indoors - with those in the north east (76%) most likely and those in London (64%) least likely to do so.
Andrew Lowe, Direct Line's head of home insurance, said the ban would also affect the health of people sharing homes with smokers.
He said: "We would estimate that there will be more deaths, based on the research. We are estimating that the ban will result in 100 more house fires a year, and some of those are going to be fatal.
"In 2005, 110 deaths occurred in fires related to smoking in the home. If smoking in the home is going to increase, then deaths in the home will increase as well.
"We were concentrating on the impact on fires rather than health, but of course smoking in a confined space when other people are around will affect them as well.
"We're absolutely not against the ban. What we're doing is highlighting the safety issues of smoking in the home."