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.
By Andrew Alden. Basalt is the dark, heavy volcanic rock that makes up most of the world's oceanic crust. Some of it erupts on land, too, but to a first approximation basalt is an oceanic rock.Compared to the familiar granite of the continents, basalt (ba-SALT) is darker, denser and finer grained.asalt is a type of lava that the rocks of the mantle make when they start to melt. If you think of basalt as mantle juice, the way we talk about extracting oil from olives, then basalt is the first pressing of mantle material.