Hansen's disease, also known as leprosy, is a chronic bacterial disease that primarily affects the skin, peripheral nerves and upper airway.ansen's disease, also known as leprosy, is a chronic bacterial disease that primarily affects the skin, peripheral nerves and upper airway.
1 Direct-vent gas fireplaces cost $1,000 to $3,500, plus $500 to $1,000 for installation. 2  The cost of a ventless gas fireplace is $500 to $2,500, and while there are additional installation costs, you may pay extra for finish work (such as a mantle, marble surround, etc.). The cost of a ventless gas fireplace is $500 to $2,500, and while there are additional installation costs, you may pay extra for finish work (such as a mantle, marble surround, etc.).
Cost of ventless gas fireplaces. Yeager charges around $900 for a ventless gas fireplace installation that includes gas logs, which typically cost between $200 and $300 if purchased separately. Gas logs for vented fireplaces cost $1,200 to $1,400, he says. Swerdlin, whoâs only licensed to install vent-free fireplaces in Maryland, says the fireplaces have improved over time and remain a convenient option. âThere are no liners you have to deal with and no chimney issues,â he says. â[Low] cost and heat are the top reasons people want them.â.