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Putney Extension

What extensions are allowed in Putney and likely costs for rear, side, single and two storey building projects.

Single Storey Extensions in Putney The simplest and most cost effective way to extend your home apart from a loft conversion is with a one-storey rear extension or side return which builds on the ground floor only. Two Storey Extensions in Putney To maximise your return on investment, adding a second storey to your extension will often double the newly created space, but at a lower cost per square foot or metre.

Cost of building an extension in Putney

When deciding whether to build a one storey extension or go for two or three storeys, it’s worth considering the lower cost per square metre that extending more than one storey involves. Put simply, you have to build a foundation and a roof, no matter how many storeys you put in between – this means your average cost per square metre gets lower, as you add more storeys and so share those fixed basement and roof costs across more square metres.

The calculation is not always that simple, but the principle generally holds. When you talk to us about your plans, we ensure you know all the possible options, so you can choose the best option for your needs and budget.

As a rule of thumb, the overall cost of a single storey extension in Putney will range from £2,300 to £3,400 per square metre, depending on the quality of finishes you select. A two-storey extension will create around twice the internal area and is likely to cost between £2,000 and £3,000 per square metre.

Putney Rear and Side Extension Regulations

The local planners who assess and approve extensions in Putney will look at whether your scheme is consistent with the conservation area you’re in and check that it doesn’t reduce the amenity of your neighbours’ properties.

There are lots of other detailed restrictions and permitted development may also not apply to homes in a conservation area, so most property owners work through the planning process with an architect familiar with the rules and local interpretation of them.

Do I need a Certificate of Lawfulness for a Putney Extension?

While it is usually not essential to obtain a COL, you may find it hard to later sell your property without one, as this little piece of paper proves that the work on your property is lawful and in keeping with building regulations.

How Long does a domestic Extension take?

A standard side or rear extension will usually take between 10 and 20 weeks to complete, depending on the design and finishes you choose. A simple one-storey rear kitchen extension will be quicker than a more complex build involving a party wall or lower-ground excavation.

What does an architect cost to design an extension?

While this will always depend on the scale of your project, a general rule of thumb would be to budget between £3,000 and £8,000 for an architect to design for you. Additional costs might include the few hundred pounds to submit the planning application (if one is needed) and then later the creation of a builder’s plan which will likely need engineer’s calculations. Finally, a full-service architect like us can also put your project out to tender, so you can get competitive quotes from builders we know to be reliable. Doing this process with a local architect vastly improves your chances of finding contractors that are good value, reliable and produce a high standard of work, because the local architect has much more experience of which are the good and which the not so good to work with in your area.

Can my extension be classed as a Bedroom in Putney?

The short answer is yes, but only if the conversion is done in compliance with building regulations. If you want the property to be valued with the extra space as bedrooms (e.g. by an estate agent) the conversion needs to be signed off fully regulation-compliant as such. The extra property value created by having more bedrooms tends to mean the extra cost of meeting regulations is well worth it.


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