When a fireplace smokes, it should be examined to make certain that the essential requirements of construction as outlined in this bulletin have been fulfilled. If the chimney is not stopped up with fallen brick and the mortar joints are not loose, note whether nearby trees or tall structures cause eddies down the flue. To determine whether the fireplace opening is in correct proportion to the flue area, hold a piece of sheet metal across the top of the fireplace opening and then gradually lower it, making the opening smaller until smoke does not come into the room. Mark at the lower edge of the metal on the sides of the fireplace. The opening may then be reduced by building in a metal shield or hood across the top so that its lower edge is at the marks made during the test; or the trouble can generally be remedied by increasing the height of the flue.
Outdoor fireplaces range from simple makeshifts to elaborately equipped structures harmonizing with the architecture of the house.
No one type will meet all conditions, but all types should be practical to use and yet not be fire hazards or eyesores.
Figure 40.—A, A fireplace built for 30 cents, cash. One hundred and twenty bricks and six concrete blocks were picked up a few at a time along the road. One sack of cement was purchased, one-half of which was used for another job Sand was available on the site. B f Detailed drawings show dimensions of this fireplace. As the fireplace is ordinarily built, the material would cost about $5 and the labor from $5 to $10, depending on local conditions.