Gas-fired boilers installed after 1 April 2005, and oil-fired boilers installed after 1 April 2007, must be condensing boilers, whether they are replacements or new installations.
Condensing boilers are more efficient than ordinary boilers as they:
Produce less carbon dioxide while still meeting heating needs
Reduce the amount of heat that is lost through the flue
Convert 86 per cent or more of the fuel they use into useful heat
The new standards apply only if you decide to change your existing hot-water central-heating boiler or if you decide to change to one of these boilers from another form of heating system.
In general, but with certain limitations, registered installers under the Competent Persons Scheme may also carry out associated building work necessary to ensure that the appliance complies with the Building Regulations, without involving Building Control.
The fuel burning appliance installer should provide you with information about the safety performance limits of the installation and, in cases where the hearth, fireplace, flue and chimney are intended as permanent features of the building that might need alteration in the future, should also fix a notice plate in a place where it will be readily seen.
If you are having a boiler installed, your installer should leave you with a completed installation record; a commissioning certificate; and a User Instruction Manual
All installations need to be certified as being installed and commissioned by a competent person. This can be done through:
A competent person certifying the work using an approved commissioning certificate.
Applying for approval through the local Building Control Body.
Further information is available from the Planning Portal and the BCA Boiler Flue Technical Guidance Note.