Conservatories are often under-utilised because they can be freezing cold in winter and unbearably hot in the summer. Replacing your conservatory with an extension could provide additional valuable usable space and add value to your London property.
Do I need planning permission to replace a conservatory with an extension?
In many cases, you will not need to obtain planning permission to replace your conservatory with an extension, as it will fall under permitted development rights. However, this will depend on several factors, including the footprint and height of the new extension, the type of property you own, and where in London you live.
While you may not need planning permission for your new extension, you must still comply with building regulations. This is because conservatories are classed as temporary structures closed off from the main property, while an extension would be treated as an extension of the property itself, essentially just another room.
To be certain about which rules and regulations your new extension will need to comply with, it is always a good idea to get the help of professional architects or other planning consultants to ensure you stay on the right side of your local planning department.
Could renovating the conservatory be a better value improvement?
Renovating your conservatory could be a cost-effective alternative to replacing it with an extension and would be less disruptive, too. As part of the renovation, you could upgrade the doorway connection with your property to create a better flow, lay a new floor, replace the roof, and improve the insulation throughout to make the space more useable throughout the cold winters and hot summers. However, it is worth considering that if you change almost every aspect of your conservatory, the costs will add up, and a purpose-built extension may be a better option.
How much does it cost to replace a conservatory with an extension?
If you are replacing your conservatory with an extension, you must first factor in the cost of removing the old structure. This can vary depending on the size and style of your conservatory, but you should consider the removal and disposal of the frame, glass, if not being reused, and rubble if you need to replace the foundations.
Once you have removed the old structure, you are looking at the cost of building a new extension, which generally costs somewhere between £1,500-£3,000/m² depending on the style and size of the extension you are looking to build and any permissions you may need to obtain.
For a clear idea of the total cost to demolish your old conservatory and build a new extension in its place, you should look to get a quote from a reliable building firm that can accurately assess the amount of labour and materials involved.
Will replacing my conservatory with an extension add value to my home?
Some people may treat their conservatories as additional living space, but the reality is that a conservatory should not be considered part of the permanently habitable area of your home. It is too hot in the summer, too cold in the winter, and so does not bring value to your property all year round. In contrast, an extension creates additional real liveable space that is integrated with your home, so as long as it is well designed, built to a high standard, and finished well, then it should add value to your home. One recent study found that a home extension’s return on investment (ROI) can be as high as 71%.
Alongside the added value, replacing your conservatory with an extension will also likely reduce your heating bills in the winter due to the improved insulation. It should, in general, improve the quality of your property by giving you extra space, whether that is used to extend the kitchen, for a home office, or anything else.
Who should I talk to about replacing my conservatory with an extension?
If you are looking to replace your conservatory with an extension or extend your property with a side return or rear extension of any kind, then Good London Builders can help. Call us today on 0207 978 5097 or get in touch online.


