top of page
  • robin flindell

Our Guide to Extensions

If you’ve reached this page, it’s probably because you are interested in an extension to your home and are researching ways of how to go about. From working out your budget, thinking of the different design options that could work and considering what level of professional help you may need, there is lots to think about! This guide aims to give you some pointers – if you’d like to get in touch to discuss any of the content in further detail, please feel free to give us a ring.

kitchen extension london improvement architect design loft conversion refurbishment


Whilst you may wish to extend your property for practical reasons, with your largest financial investment on the line a sensible starting point is to consider the value that could be added. Building an extension is a great way to add value to your property, but it’s not always that simple. Depending on your location there is a price ceiling on every property so don’t extend for the sake of it. Start by looking at properties nearby, on websites like Rightmove or Zoopla, that have been extended, to gain inspiration.

Adding an extra bathroom may add more value to a larger property, over adding another bedroom or extending the living space for example, as potential buyers in that bracket want certain amenities over others. Or indeed creating a ‘top heavy’ property, by adding extra bedrooms when there is only a small reception and kitchen area, will likely put off prospective buyers with large families as there is not enough living area.

Build something better

Try to make your property better than what already exists; open-plan living and kitchen areas are very popular at the moment, but it is also worth having a separate living room or study space too to create a range of different spaces. Make sure that your extension has a unique selling factor that will put you head and shoulders above your competition nearby to get the best price.

Consider a sensible budget

Work out how much equity you have in your house and make sure that you don’t need to eat into especially if you are not confident that your extension will add enough value to recoup the costs. Bearing in mind the ceiling values in your area, there is a limit to how much extra value can be added by installing higher specification finishes over basic finishes.

kitchen extension london improvement architect design loft conversion refurbishment

Construction costs vs. potential value added

We’ve included some ball-park construction costs based upon our experience, excluding kitchen and bathrooms.

  • Single-Storey Rear: £30-40k

  • Two Storey: £50-60k

  • Wraparound: £40-50k

  • Conservatory: £15-25k

These figures are based upon a standard finish base-build cost of between £1,500-£2,000/sqm, which would include:

  • Mid-range uPVC or cheap aluminium doors and windows

  • Standard brick, block, tile construction.

  • Good levels of insulation

  • Simple design with a simple pitched or flat roof avoiding extensive areas of glazing.

  • Internally plaster with paint finishes and relatively low cost flooring and tiling.

  • Basic lighting and sockets.

  • Extending an existing radiator based heating system.

To work out how much value could be added to your home there are some excellent resources available based on data. Check out this link from rightmove to give you an idea.

If you’d like to get some more advice on budgeting for your extension, please feel free to give us a call.


Common types of extension

Depending on what type of property you own will often dictate what kind of extension you can build. A terrace house will be most suited to a single storey addition, whereas a semi-detached or detached can benefit from a wrap-around extension.

Single storey rear extension

A rear extension, if you have the garden space to spare, will make a big difference to your living space and often allows you to create a large, bright and airy kitchen-dining space that opens up to the garden.

If you’re used to living in a Victorian terrace where none of the rooms have yet to be knocked through, this will be a breath of fresh air and revolutionise your family living.

Things to consider with this type of extension is it will probably affect your existing kitchen during the build, so being able to put up with building work is a must. If living in a terrace, all materials will need to be brought through the front door so make sure your builder allows for making good any finishes through here that could get damaged.

Two storey extension

kitchen extension london improvement architect design loft conversion refurbishment

If you’re able to and have the funds, an extension across multiple levels can revolutionise your home and gives you the opportunity of changing the buildings appearance. You can expand your living space, add on new bedrooms and bathrooms or maybe a utility space or balcony terrace. Whilst this will cost more than just a single storey extension, rooms like an extra bedroom generate a lot of new value as well as potentially making your house stand out from the crowd in a competitive marketplace.

Other things to consider is that building a two-storey extension could involve more wrangling with the planners, as they may need to understand if your two storey extension adversely affects your neighbours, before giving permission.

Wrap around extension

kitchen extension london improvement architect design loft conversion refurbishment

Like a rear extension, but it also incorporates any available side space. Period properties often have alleyways to the sides to access the rear garden that this type of extension will cover.

18 views0 comments

Recent Posts

See All


bottom of page