Replacing an external door in England and Wales is notifiable work under the Building Regulations, and the new door has to meet Part L for energy efficiency. Two routes satisfy that. A FENSA or Certass registered installer self-certifies the work. If you fit the door yourself, you notify your local authority Building Control instead.
People use the terms interchangeably and they cover different ground, which is where most confusion starts.
Planning permission is about what the outside of your house looks like and how it affects other people. Replacing a front door in the same opening almost never needs it.
Building Regulations are about how the work performs: energy efficiency, safety glass, ventilation, structural support. Replacing an external door does engage them, every time.
You can therefore need one and not the other, which is the normal situation for a door replacement: no planning permission, but yes to Building Regulations.
Three situations change the answer. A listed building needs listed building consent for a door replacement, and proceeding without it is a criminal offence. A house in a conservation area may be subject to conditions on material and design. And a flat or maisonette is outside permitted development, so a leaseholder needs both freeholder consent and, often, permission.
Moving a front door to a different position is a separate matter again. Forming a new opening in a load-bearing wall and closing the old one is structural work, it needs Building Regulations approval on the structure as well as the door, and depending on your house it may need planning permission too.
Part L sets a maximum heat loss for a replacement door. A door sold for the UK domestic market is built to meet it, so this is rarely something you have to solve. It becomes your problem when you cannot show that it was met.
Read more about UK regulations here
Where glass sits decides whether it has to be safety glass, and a front door falls inside the critical zone by definition.
Standard glass is allowed only where the bottom edge of the glazing sits more than 800 mm above the finished floor and not within 300 mm of a door opening.
Toughened or laminated glass is required where the glazing sits below 800 mm, where it is in a door, or where it is within 300 mm of a door edge and below 1500 mm. A permanent barrier in front of the glass is the alternative.
A glazed front door needs safety glass in the door. A sidelight beside it almost always needs safety glass too, because it sits within 300 mm of the door edge. Both are options you select when you configure the door.
Part F expects a room not to end up with less ventilation than it had. Replacing a door that carried a trickle vent with one that does not reduces the ventilation of the hallway, and that has to be made up somewhere.
Most hallways draw their ventilation from the rooms around them rather than from the front door, so this is a smaller issue on a door than on a window. It still gets asked about, so plan the room rather than the door.
This is the part that catches people out, and it is worth reading before you order rather than after.
Buy from a company that supplies and fits, and if they are registered with FENSA or Certass, they self-certify the installation. You receive a certificate and nothing else is required of you.
Buy the door on its own and fit it yourself, or use a joiner who is not registered with either scheme, and the work has to be notified to your local authority Building Control. You apply, they inspect, and they issue a completion certificate. There is a fee, and the timescale is theirs rather than yours.
Contact Building Control before the door arrives. Ask what they need and how long they take. Some authorities accept a building notice a few days before work starts, others want longer.
Keep the paperwork from the door. The specification, the glass type and anything showing the thermal performance. That is what an inspector asks for.
Book the inspection. Some authorities inspect on completion only. Others want to see the opening before the door goes in.
File the certificate somewhere you will find it in ten years. This is the step people skip.
A buyer's solicitor asks for evidence of Building Regulations compliance on any notifiable work done since 2002. A missing door certificate will not stop a sale, but it turns into an indemnity policy, a retention or a price reduction, and it does so at the point in a transaction where you have the least leverage.
The cost of getting it right at the time is a fee and a phone call. The cost of not having it is negotiated years later by someone else's solicitor.
