Working out what is cheaper – a loft conversion or an extension for your home isn’t always easy. You have to factor in your needs, budget, available timeframe, and a whole load of other aspects that could impact what it costs you overall in real terms.
Generally speaking, a loft conversion is going to be cheaper than an extension, but not all lofts are allowed to be converted. We’ll be taking a look at the costs of both and examine what else matters when deciding if you should opt for a loft conversion or an extension.
Key Takeaways
- Loft conversions are almost always cheaper than extensions
- Not all lofts can be converted, so sometimes an extension might be your only option
- Extensions take a lot longer and will be more disruptive to your life at home
- A home extension will give you more additional space than a loft conversion and the value it adds to your home will almost certainly be greater
How Much are Loft Conversions?
According to a survey conducted by the Royal Institution of Chartered Surveyors (RICS), the average cost of a loft conversion in the UK is around £30,000 to £50,000, while the average cost of an extension is between £50,000 and £80,000.
Checkatrade recently carried out its own investigation into loft conversion and extension costs in the UK and determined that the average loft conversion cost ranges from £27,500 to £75,000 with the average cost of an extension ranging from £25,000 to £112,500.
You will notice that in both loft conversions and extensions the bottom end (lowest average cost) remains about the same, but the upper range is significantly higher (approximately +50%) meaning both loft conversions and home extensions have become more expensive in recent times (adjusted for inflation).
There are also different kinds of loft conversions each with its own average costs.
| Common Types of Loft Conversion | Average Cost (London) |
|---|---|
| Dormer Conversion | £45,000 |
| Hip-to-Gable Conversion | £50,000 to £75,000 |
| Mansard Conversion | £45,000 to £75,000 |
London Loft Conversions & Extensions
In London, the current average cost of a loft conversion is between £45,000 and £90,000 whilst the average cost of a ground floor rear extension in London (the most popular kind) is between £85,500 and £135,000.
In terms of estimating how much loft conversions cost for your own property, both loft conversions and extensions are normally calculated by cost per square metre (m2).
Today the best estimates suggest that you will be looking at paying between £1,200/m2 and £2,000/m2 for a loft conversion and anywhere from £1,800/m2 to £2,600/m2 for a home extension.
How Much are House Extensions?
There are a number of different types of house extensions and we give you the average cost of each in the table below.
| Type of Extension | Average Cost (London) |
|---|---|
| Single-Storey Rear Extension | £40,000 to £60,000 |
| Double-Storey Rear Extension | £70,000 to £120,000 |
| Side Extension | £50,000 to £80,000 |
| Wrap-Around Extension | £80,000 to £120,000 |
| Basement Extension | £100,000 to £150,000 |
As mentioned above, single-storey rear extensions are the most popular in London given the prevalence of terraced properties and the fact that they are cheaper than other types of extension.
A wrap-around extension involves extending both the rear and side of a property, creating additional living space on two sides of the house.
Basement extensions are by far the most expensive and complex because of the excavation process that is required, the need for additional structural support and additional waterproofing measures that must be undertaken.
Loft Conversion or Extension?
It is clear that loft conversions are significantly cheaper than extensions, but that isn’t the only difference.
When it comes to how long it will take to complete a loft conversion vs a house extension there is also a wide discrepancy between the two kinds of projects.
Regardless of the type of loft conversion you go with, the vast majority will usually take around 4 to 10 weeks to complete. Home extensions, on the other hand, normally take much longer and can last between 3 to 6 months if not more.
A home extension is also going to cause a lot more disruption to your daily life so you need to consider how much of this disruption you are able or willing to tolerate before committing either way.
Frequently Asked Questions (FAQs)
How Much Value Does a Loft Conversion Add?
The figure generally offered is about 20%, but there are no guarantees a loft conversion will add that much value to your home. For a full examination of the value loft conversions could add to your property you should take a look at our write-up.
How Much Does it Cost to Extend a Kitchen?
Costs can range anywhere from £12,000m to £100,000+ but on average in the UK a kitchen extension will cost about £30,000. That figure rises to £50,000 in London.
Is it Cheaper to Extend Up or Out in the UK?
It is definitely cheaper to extend up rather than out in the UK, though you should always consider that the additional value added to your property by extending out will almost always exceed that of extending up by a significant margin.
Conclusion
We have seen that loft conversions are cheaper, cause less disruption to your daily life and will be completed faster than house extensions.
There is also the added benefit that most loft conversions do not require planning permission, which is often not the case with an extension.
London Lofts have years of experience carrying out loft conversions on all kinds of properties throughout London. We are experts not only at building loft conversions but also securing planning permission on the rare occasions it is required.
So, if you are leaning towards converting your own loft why not get in touch for an initial consultation today?
