Start A Project

Cheap Home Extension Ideas

Do you need more living space or want a more functional living area without having to spend a fortune? We’ve put together several cheap home extension ideas to inspire you to get creative and think about how you can improve your home if you’re on a tight budget.

Convert instead of Extending

If your home has existing space that isn’t really being used, such as a loft or a garage then these could be converted into usable living space.

This has a number of cost saving benefits –

  1. No/reduced build costs – the structure is already in place
  2. Unlikely to require planning permission
  3. No need for ecological reports/agreements (unless the work involved modifications to shared walls/structures)
  4. Reduced labour costs
  5. Reduced professional fees (less likely to need to employ an architect/require hired management for the site)

A conservatory is a cheap, easy extension idea to add extra living space. They can extend by a maximum of 3 meters from the rear of the property and also have a height restriction of 3 meters without needing planning permission or prior approval.

Converting a Loft

The cheapest type of loft conversion is a ‘Room Loft Conversion’. This is where you board out the loft and add a staircase. Maybe add a few skylight windows in the slope of the roof. You would require a good sized loft with good head height. The best roof type for the loft extension is a gabled roof (2 sides slope) rather than a hipped roof (all 4 sides slope). Always remember, you may lose a bit of space on the floor below when installing the staircase. Loft conversions are great for creating an extra bedroom, maybe with an ensuite.
Prices start from £15,000

Additional types of loft conversions include:

Dormer Loft Extension
A dormer loft extension is where a big box is typically added to the rear of the roof. This gives lots more space. Typically created via permitted development.
Prices start from £20,000 or from £35,000 with the inclusion of an en suite

Hip to Gable Roof Extension
There is a permitted development where you can do a hip to gable extension (changing the roof from all four sides sloping in towards the middle to just two sides sloping) – usually on a semi detached property. Councils do not like this type of development as it will unbalance a semi detached pair but if done correctly at permitted development, the council can not stop it.
Prices start from £25,000


Converting a Garage/Basement

Turning an existing basement/garage into a usable living space costs from £700 per square meter for the build costs

Other cost factors that you may need to consider include:

  • Will you need to move your boiler/consumer unit/gas meter?
  • Will you need to underpin (reinforce existing foundations)?
  • Will you need to lower the floor to increase ceiling height?
FREE GUIDE: Category: Home Extensions
FREE: Home Extension Cost Guide

Inside this easy to ready free guide, you will learn how much extensions, loft conversions and other renovations to your home are typically priced.

Build a Conservatory

A conservatory is a cheap, easy extension idea to add extra living space. Conservatories are usually allowed under permitted development rights, which means that you can build a single-storey rear extension of up to 8 metres from the original rear wall of a detached house, or up to 6 metres for any other house without needing planning permission (conservatories over 4 metres (for a detached house)/3 meters (for a semi-detached/terraced house) are subject to the Neighbour Consultation Scheme).

A conservatory could be a great dining area, freeing up space for a larger kitchen/lounge area in your home.

DIY, ready-to-install conservatories can cost as little as £3,000 or a mid-priced design that will be comfortable even on hot and cold days can cost from £15,000.

Build a Summer House

If you need extra space but don’t necessarily need it attached to the main home, another cheap extension option is a summer house/hobby room. A quite generous size can be easily achieved under permitted development unless the unit will contain a toilet and kitchen (then the building will be considered a self-contained unit and may need planning permission).

Costs vary depending on the size, quality, level of insulation, type of interior and exterior finishes etc of the summer house/hobby room but a cheap, modular kit can cost as little as £2,000

Interior Fit-Out Cost

Fit-Out costs vary greatly depending of the function of the room (mainly affected by the cost of appliances) so if you’re looking to keep costs down, re-use what you can and if you need to replace then shop for affordable flooring, lighting, units, appliances etc

  • Kitchen
    Budget from £7,000 to £15,000 – the biggest cost factor is the appliances – the better the appliances, the higher the cost

  • Bathroom
    Budget around £5,000 assuming you can connect to existing pipework

  • Utility Room
    Budget from £1,500 to £11,000 depending on size and quality of appliances

Share this...

Share on facebook
Share on google
Share on twitter
Share on linkedin

Additional ways to reduce costs

  • If knocking down walls/rooms, consider what materials you can re-use
    (flooring, tiles, bricks, cabinets/units etc)

  • Consider re-facing instead of replacing
    For example, if your kitchen cabinets are in great condition, you could just re-paint them or replace the doors and drawers as part of your kitchen renovation

  • Building Regulations
    All extension work requires building regulations approval and you may need building regulations approval for many alteration projects. This can cost from £400 – £750. However, you do not need to get approval yourself if you use traders registered with a competent person scheme.


Total Cost

To calculate the cost of your project, Yoop Architects take a measured survey of your property, which captures all the information. Then we draw it all up in 3D and create sketches to show sometimes five or six options if it’s not entirely clear how you want to achieve your brief.

A lot of the times there are different ways of achieving your desired result and the more you work with the building, the cheaper, easier and faster your build will be. Once you’ve got a favorite scheme or a couple of favorite schemes, we have a phase called ‘Meet the Builders’. That’s when we can introduce you to a couple of builders, they visit the property and they give you a ballpark figure.


Thinking of your dream home improvement or how to start your project? 
Need your planning questions answered? Talk to an expert today.
Book a FREE 20 Minute Call with one of our home improvement Architects.

Connect with Yoop Architects...

Share on facebook
Share on google
Share on twitter
Share on linkedin

Post Author: yoopadmin