Zero Clearance Fireplaces - Ready to Install
Pre-fabricated vs Traditional Masonry Fireplaces
Zero clearance fireplaces are factory built units made from sheet metal or cast iron. They are also known as pre-fabricated fireplaces because they come ready to install complete with instructions on how to assemble the unit and a description of the framework requirements.
These types of fireplaces are used by professional builders and inexperienced homeowners. Zero clearance fireplaces are so named because they are sufficiently insulated to be installed within close range of combustible materials, such as walls or wood framework, without requiring a masonry foundation.
Pre-fabricated fireplaces are gaining popularity over the more traditional masonry fireplaces for a number of reasons. The most prevalent is that they are easier, quicker and much cheaper to install than a masonry fireplace. They also tend to be more energy efficient. The average open masonry unit is only 15 percent efficient whereas some zero clearance fireplaces have an efficiency of up to 70 percent or more. The reason for this is because the open fireplace does not get hot enough to burn the pollutants it produces. There have been a number of innovations that have improved the heat and fuel efficiency of fireplaces.
These innovations include catalytic fireplaces, glass doors and the built-in heat exchanger found in many pre-fabricated models. These heat exchange systems use vents to take in outdoor air for combustion as well as exhaust the pollutants. They also have ducts that take in room air to be warmed in the firebox and then circulated around the room using a blower .
Zero clearance fireplaces come in a huge variety of designs and can be made to look like conventional masonry fireplaces by simply enclosing the metal unit in masonry framework. When buying a pre-fabricated unit there are a number of things that need to be taken into consideration. Firstly, always look for a certificate stating that the unit has been properly tested and inspected.
The other very important factor in buying a zero clearance fireplace is the size of the firebox opening. This needs to be relative to the size of the room or area that it will be required to warm. A general rule of thumb is that for every foot of room space measured approximately an inch should be added to the width of the firebox opening. This is important because if the opening is to big a lot of energy and money will quite literally go up in smoke. If the opening is too small the heat produced will not be enough to warm the room. A building permit may also be required and local building codes should always be consulted before installing a zero clearance fireplace.
Another consideration is where to place the unit. The very definition of zero clearance means the unit can be placed just about anywhere but it is a good idea to consider the practicalities first. Choosing a position with the shortest and most direct route for the chimney is important as it means less disruption to the structure of the building. Planning the layout of the room is crucial to ensure that the position of the fireplace in relation to the rest of the furniture is aesthetically pleasing as well as practical. Never position a fireplace in an area of the room that gets the most traffic as it can be a nuisance as well as a hazard. Once the new unit has been installed instructions on proper operation should be strictly adhered to. A grate should also be used to protect the brick lining. The first five or six fires should be small in order to 'burn in' the new unit and bigger fires can then be introduced gradually.