In this special episode of Ask This Old House, Tom Silva and Mark McCullough tell you everything you need to know about fireplaces; Tom builds a custom mantel for a homeowner; Richard Trethewey discusses fireplace inserts; Mark replaces the hearth of a fireplace with granite.

Nathan Gilbert helps a homeowner turn a reclaimed beam into a fireplace mantel; Richard Trethewey shows how to change a bathroom faucet; Ross Trethewey explores innovations to geothermal installations.