Solid fuel designs
Solid fuel fires come in two types. The open fire is often just a basket or grate for burning coal, smokeless fuel or wood. They look good but may not be particularly efficient and quite difficult to control. Consider closed designs with glass doors and convection channels. These designs burn efficiently by utilising clean-burn technology to wring the maximum amount of heat out of the burning fuel. An adaptation of the system also keeps the glass on the door clean. Some designs allow air to be ducted from the heat exchanger to other rooms.

A compromise between the open fire and glass-fronted solid fuel designs is the convector fire. Designed as a steel box within another steel box, convected hot air radically improves the fires efficiency without the need for a glass front.

Gas fires
Gas fires come in more types than solid fuel fires. Whilst models designed for conventional flues are still the norm, the past two decades have witnessed an immense growth in both balanced and fanned flue models. While the balanced flue uses the effect of burnt fuel exiting the flue pipe to pull in more air for combustion, the fanned flue (as its name implies) uses the fan to pull air and exhaust gases through the fire and dissipate them to the atmosphere.

 Many of today's designs come in all three options creating a situation where, if gas is available, there must be a design that will fit. Remember balanced flue fires don't need a power supply but must be on an outside wall whereas fanned flue fires have some fan noise but are very flexible in fixing.

Electrical fires
The flame-effect fire, pioneered by Dimplex, has changed purchaser's perceptions of how a fire can look. Many of today's designs really do resemble fires (look at the Katell fire in our picture) and have been sized to inset into standard fireplaces or into a swish new fireplace surround. Aesthetics are the key feature of the electrical designs - their outputs are limited to 2 kW by the capacity of the 13-amp ring main. Alternative designs boast LED flame effects, glowing 'coal s' or flames created through projection onto a series of mirrors.  Look around the market to find the effect that you require.

Points to remember

• Solid fuel fires typically need a chimney or flue bigger than 7" in diameter or cross section.
• Pre-cast gas flues are only suitable for gas fires and only for some gas fires at that.
• Decide whether heat or aesthetics are what you want. A high heat requirement may rule out both electricity and gas.
• Consider whether you have the time available to maintain an open solid fuel fire.
• Both gas and solid fires need ventilation and this may mean installing a vent in the floor or wall.