About Hearth Pads

Features

• Both free standing wood and coal stoves and masonry stoves require hearth pads. Hearth pads under free standing stoves cover the entire flooring space under the stove and extend around the stove, making a heat-resistant boundary. In masonry stoves hearth pads make the lowest part of the stove or fireplace. The firebox lies over the hearth pad in a masonry stove. Hearth pads are made of non-combustible heavy material that can withstand the weight of the free standing stove or the masonry stove.

Functions

• Hearth pads prevent overheating and igniting the floor beneath a free standing stove. Hearth slabs also add to the beauty of the décor and make loading and cleaning both free standing and masonry stoves easier. Hearth pads also provide ember protection because they form a fire-resistant boundary extending around the perimeter of the stove.

Size

• The size of the hearth pad depends on the size of the fire box. Hearth pads should completely cover the floor below the firebox and extend around the perimeter of the firebox. Hearth pads should extend to at least 16 inches in front of the firebox and eight inches from the sides of the firebox. Hearth pads should extend eight inches from the back of the firebox if a free standing stove is not placed against a wall.

Material

• Brick, stone, concrete or ceramic tiles make good hearth pad materials. Sandwiching sheet metal between the hearth pad and wooden subfloor prevents sparks or embers from reaching the subfloor. Sandwiching backer boards like Wonderboard or Durock also help to prevent embers from burning through to the subfloor.

Considerations:

• Hearth pads should conform to the standards laid down by the Underwriter's Laboratory (UL) and the standards laid down by the National Fire Protection Agency. Placing hearth pads that conform to these standards ensure that insurance companies will insure the home against fire hazards. Cement boards with low K factor for hearth boards ensure that a small amount of heat conducts through the board. Hearth pads are not required in masonry stoves if set on a reinforced slab. Concrete hearth pads for masonry stoves should have cement mixed with silicon sand and gravel. The conventional limestone aggregate melts and causes the hearth pad to loosen.