Your Place: Professor weighs in on insulation and ventilation

I answered an insulation question in this column not too long ago, and Joe Ponessa sent me an email in late November about it. "I don't think you gave enough attention to the issue of combustion (makeup) air," said Ponessa, professor emeritus of housing, indoor environment and health at Rutgers Cooperative Extension.

Ponessa agreed that the limited work I described did not sound as if it would cause a problem for "atmospheric" combustion appliances, which derive their air from the surrounding environment.

There is, however, "a tipping point where draft-stopping will prevent adequate combustion air when all combustion appliances are operating simultaneously," Ponessa said. For this reason, "my colleagues who specialize in energy state that all weatherization projects should include a backdraft test to assure that combustion gas spillage does not occur."

He noted that he didn't know where the line might be drawn between modest draft-stopping and that serious enough to warrant back-draft testing.

An expert should be able to offer some insight into this, he said, and "I think it would be a beneficial follow-up for your readers."

As for keeping your home warm, don't forget to have your furnace checked out by a professional before winter gets any colder.

Contact Alan J. Heavens at aheavens@phillynews.com or write him at The Philadelphia Inquirer, Box 8263, Philadelphia PA 19101.

This story was originally published January 6, 2016 at 9:29 PM with the headline "Your Place: Professor weighs in on insulation and ventilation ."