Lining Duct Work

Hello All, I've been dealing with some air noise from my HVAC system in my studio. I've got a real basic question about using duct liner. Currently the air feeds into the studio are sheet metal 14x10 ducts. They are not lined. I can't entirely modify the duct work without making a huge mess, however I think I can slide some duct liner/insulation into the existing duct through the vent holes. I have some 1" certainteed board, alot like faced 703. My question is this: Is it safe to use this board on the inside of duct, especially from a breathing stand point. And if it's ok to use, which direction do I face the foil? Do I have the yellow insulation against the exisiting sheet metal or do I put the foil against the sheet metal?? Ultimately, I'm just trying to reduce some air nosie and whatever other noise is travelling through the ducts... I'll only be able to lay the board on the bottom of the duct... thanks:) andrew

you are probably better off getting some duct liner specific for the task. John Manville makes 1" duct liner which should serve you better. the other insulation is likely to end up feeding fibers into your air flow.

Glenn is correct = you want a specific product - and you can get it from all of the manufacturers. Duct liner that has polymer surfaces so yu don't have to worry about loose fibers........ Rod

Thanks Guys!