Changing your doors

When renovating a property, there are three options when it comes to upgrading the doors:

  • either overhaul the existing door and frame
  • replace just the door itself
  • or fit a combined new door and frame 

Much will depend on the size of your budget as well as the condition of the existing door and the age of property. For example, fitting a new UPVC front door on the front of a period house is one of the quickest ways to wreck its character, and can also have planning implications. So for historic homes, upgrading the originals or replacement with an exact replica is normally the best bet. But it’s not just main entrance doors that can benefit from replacement. If you want to introduce some architectural flair upstairs, it may be possible to replace conventional bedroom windows with glazed, inward-opening double doors, enclosed externally by a discreet cast iron ‘Juliet balcony’. Similarly, renovating or replacing the interior doors can transform the appeal of a property.


Planning permission is required in conservation areas for replacing front doors and any significant alterations to the principal elevation. For Listed buildings consent is also required for changing internal doors. The Building Regulations apply where you want to make structural alterations, such as enlarging an existing opening to install a wider pair of double doors. Where both the door and frame are being replaced simultaneously they are defined in Part L of the Building Regulations as ‘controlled fittings’ and have to meet minimum thermal insulation standards and achieve air tightness to frames and thresholds. With internal doors, Part B of the Building Regulations covering fire protection can sometimes apply as well as Part M for improved indoor mobility.

External doors

It pays to take a little time when picking a new door. Fitting a cheap one may leave you vulnerable to leaks as well as break-ins. Clearly it’s important to match the dimensions as closely as possible to the existing frame or opening. Older properties sometimes have awkward sized openings which may need more extensive preparatory work. So sometimes renovation and upgrading of an original door is the best option, and many good quality Georgian and Victorian doors are still going strong. Doors manufactured from UPVC are usually supplied as a complete unit with an integral frame. Their main advantage is that they are virtually maintenance-free, although they are not always as attractive looking as the traditional wooden variety. However, unlike UPVC, timber doors may not comply with the latest thermal performance standards. 

Fitting frames

Entrance doors normally open inwards, whereas ‘French windows’ or balcony doors generally swing outwards. But there’s nothing to stop you improving the layout of a kitchen for example by fitting the door so it opens outwards to the garden to save space internally.

When installing new frames, it’s good practice to fit a protective strip of plastic DPC around them (as with new windows). Although timber frames are normally pre-treated, all surfaces that will abut the walls should first be painted with primer, undercoat and top coat. With UPVC frames it’s particularly important to allow for expansion of the plastic by leaving a suitable gap between the frame and the surrounding masonry, to prevent distortion. Once fitted, the joints between the frame edges and the walls should be sealed with mastic.

Rainwater is prevented from entering under entrance doors by means of threshold seals fixed into a groove on the underside of the door or to the threshold beneath the door. An overhanging ‘weatherboard’ projecting from the lower front of the door should also be fitted to disperse rainwater.

Hanging doors

The advantage of fitting a new frame and door ‘combo’ is that the frame will be designed to accept your precise choice of new door – so it should all slip easily into place. However, to ensure the frame fits the opening, some preparatory work to the masonry may first be required. New timber doors should be unwrapped and allowed a little time prior to installation to acclimatise so as to minimise the risk of bowing, warping and sticking. To achieve a good fit a certain amount of planning may be required, particularly where old frames are slightly distorted. Timber doors should be painted or varnished soon after installation so they don’t get a chance to absorb moisture and swell.

When fitting new doors, a clearance gap of about 3mm should be left at the top and sides, but you need to allow for the fact that the door will tend to drop over time. Hinges should always be fitted to the door first, before the frame. Brass hinges are normally the best option as they are not susceptible to rust. When any necessary trimming has been done and the hinge positions chiselled out and with the hinges fitted, the door can be temporarily wedged in the open position so it can be screwed to the frame. With heavier doors, such as those containing glazing, a third hinge should be placed mid-way between the main pair. Finally the door furniture and locks can be fitted.


When specifying new doors, those certified to PAS 23/PAS 24 should provide optimum security. Locks should be specified to comply with BS3621. For external doors, the best security locks are 5 lever deadlocks, plus a cylinder rim lock for front doors. The easiest type to use are mortises with lever handles that automatically operate a latchbolt and deadbolt.

Internal doors

In older properties it’s normally best to renovate the original interior doors, as they are an important part of the building’s history and architecture – plus this should work out a lot cheaper than fitting new ones. But replacing poor quality modern doors is usually well worth doing as it’s an easy way to revitalise your rooms. To boost the amount of light in a room, part glazed doors can be useful, but glazed lower door panels need to be fitted with safety glass. The age and architecture of the property is likely to influence the style of replacement doors and door furniture. In contrast to many plain modern doors, Victorian houses generally feature classic four panel designs, the Georgians had a fondness for the six panel variety, and the 1930s saw the advent of distinctive ‘one over three’ panelled doors – not forgetting the grandfather of them all, the traditional farmhouse ‘ledge & brace’ door. If you want to recreate an authentic period house feel, reclamation yards can be a useful source of traditional doors. But bear in mind that warped doors can rarely be much improved, and overlarge ones can only be trimmed by a small amount before it affects their strength.

Interior doors are lighter than their more durable external cousins, typically only 35mm thick, and are normally made of softwood. Many lightweight doors are hollow inside, comprising a simple timber frame containing a honeycomb cardboard core, clad both sides with moulded panelled sheets. Heaviest of all are self closing fire-check doors which provide a minimum 20 minutes’ resistance (‘FD20’) to the spread of fire, some incorporating an intumescent strip for added protection. You are unlikely to need these in a typical home unless the dwelling is three or more storeys high, or for doorways to integral garages (‘FD30’).

Fitting catches tends to be easier with solid timber doors. With hollow doors you need to locate the solid wood block within the frame into which they are housed. Most internal doors can be supported by a pair of butt hinges, although heavier fire doors require a third hinge and in some cases door stops may need to be made thicker. When it comes to fitting replacement doors, they normally need to match the dimensions of the existing frames, which don’t always conveniently correspond to standard 21st century door sizes. So a certain amount of adjustment is likely to be necessary. New internal door frames can be purchased in kit form comprising timber liners which are screwed to the masonry or studwork wall.