Here are a few requirements and regulations for loft conversions. If you have any questions please do not hesitate to contact our friendly staff today.



Regulations for loft conversions can and are in most cases carried out under your "Permitted Development" rights, that is provided the loft conversion falls within certain building regulations limits and considerations, however all loft conversions have to go through stringent building control regulations.

You would not normally need to obtain planning permission providing that:

  • A volume allowance of 40 cubic metres additional roof space for terraced houses.
  • A volume allowance of 50 cubic metres additional roof space for semi-detached and detached houses.
  • The property is a domestic dwelling and is not a marionette or flat.
  • The existing roof line to your property is not raised.
  • Hip to Gable side-facing windows must be obscure-glazed.
  • The building is not listed as special architectural or have historic interest.
  • The building is not located in a conservation area.
  • The proposed extension or dormer window is not raised above the highest part of the roof or slope, and does not face a public highway.


Thermal insulation is an absolute must and is to be used in all new walls and ceilings, this insulation must comply with building regulations “Approved Document E” by meeting the minimum energy efficiency values, when installing loft insulation at the eaves, extra care must be taken to ensure that they are not blocked to ensure the possibility of interstitial condensation is kept to the bare minimum.


"Approved Document Part P" of the Building Regulations requires that the installation of new electrics must conform to BS 7671:2008 17th Edition IEE Wiring Regulations. A Residual Current Device (RCD) must be installed to protect all electrical wiring carried out within the loft conversion.


Under "Approved Document A" Building regulations, new floor joists will be introduced and suspended in order for the new floor to be able to carry the new additional loads. If the existing walls are load bearing and adequate then the new floor joists may be supported on them. Otherwise additional support, such as steel / timber beams will be introduced. The new floor in the loft space must be supported at the ends on load bearing walls or from strap hangers, from beams calculated to accept the floor loads.


The building regulations in relation to staircases are laid out within "Approved Document K". Wherever possible the new staircase should rise over the existing staircase and enclosure as to give continues flow of the landing areas, a staircase that is fitted or located incorrectly can dramatically devalue a property.


When having a loft conversion, provisions for escape have to be considered for your escape route (Hallway) a mains/radio linked and battery back up smoke/heat detection system will be fitted to everyhabitable room from the escape route.


If you are an owner of a terraced or semi detached dwelling contemplating a loft conversion, this could involve some kind of work to the wall or walls between yourselves and your neighbours, these walls are classed as "party walls" and therefore you have certain responsibilities under the act, being defined as a ‘Building Owner’ under The Party Wall Act 1996.

The Act requires a ‘Building Owner’ of a property intending to carry out works to a party structure to serve notice on any affected adjoining owners. An adjoining owner cannot stop someone from exercising the rights given them by the act, but can influence how and when the work is done.