If you want to convert from an electric furnace to a gas furnace, you will need to have gas piping and ductwork installed first. This will add an additional up-front cost to the furnace and installation process of around $5,000 to $15,000 or more depending on the space. Leaky ducts can also cost homeowners about 10 percent to 30 percent in efficiency. 2  This will make a 96 AFUE high-efficiency furnace run at 66 percent to 86 percent and make an economical 80 AFUE not much better than an open fireplace. 3  The cost to replace ductwork is about $8 to $12 per linear foot of ducting.
A flood basalt is the result of a giant volcanic eruption or series of eruptions that coats large stretches of land or the ocean floor with basalt lava. Flood basalt provinces such as the Deccan Traps of India are often called traps, which derives from the characteristic stairstep geomorphology of many associated landscapes.
A lava plateau (also called a basalt plateau or flood basalt) is a special type of plateau, formed neither by the collision of continental plates nor by uplift. Instead, this layered plateau is built up over millions of years by lava repeatedly pouring forth through fissures, or long narrow cracks in the ground.