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Attention to Detail


Double Storey Extensions

A two storey extension could be the perfect way to transform your home. It is the best way of increasing living space and bedroom accommodation at the same time. If you find that your home is too small, or you have a growing family, a two storey extension could be the right solution for you.

It may also prove more cost-effective than moving house or building a single storey extension or outbuilding.

All our home extensions are finished to the highest possible standard, on time and with minimal disruption. Our polite, hard working and professional team of craftsmen will also leave your property clean and tidy at the end of each day.

How much will a two storey extension cost?

Labour costs vary across the UK – and the design, build spec and materials you choose will affect the final price – but expect to pay from around £1,250 - £2,050 per square meter.

The cost of fitting out your two storey extension will depend on the rooms within it.

  • For a kitchen, budget from around £4,500 to £16,500, depending on the specification; if you go high end, costs can increase significantly on this.

  • For a bathroom, factor in from around £4,000 to £10,000, according to the level of fittings.

  • For a shower room, plan for between £4,500 and £11,000, again depending on your level of fittings.

  • For flooring, budget in the region of £24 to £96 per square metre.

  • For wall and ceiling finishes not included in the build costs, set aside from around £77 per square metre for plaster or dry-lining plus paint.


Will I need planning permission?

Many two storey extensions can be built under permitted development rights, without the need for a planning application as long as you stay within these restrictions.

  • Your extension can’t be taller than the highest part of your existing roof

  • It must not extend beyond the rear wall by more than three meters

  • It has to be at least seven meters away from the boundary.

  • It has to be built in materials to match the original structure.

For homes in conservation areas, further restrictions apply.

  • You have to apply for planning permission on all extensions over one storey

  • You can’t add any exterior cladding without permission

  • No side extensions without planning permission


What do I need to know about building regulations?

You’ll need to get Building regulations approval. These are minimum standards set to control health and hygiene, safety, welfare, convenience, energy-efficiency and sustainability of a building project. Each local authority has its own table of charges or you can use a private certified building control firm if you prefer.

The size of your extension will affect the fees for building regulations approval. Plan for from £250 for one to 10 square metres, and £900 for 80 to 100 square metres, whether you go for a full plans application with everything approved before you start, or a building notice application, where you need only give 48 hours’ notice of commencement.

Party walls

‘If any neighbours who share a boundary wall with your property consent formally to the extension, you won’t need a Party Wall settlement and can save money. If not, having a surveyor arrange party wall agreements for you typically costs from £700 to £1,000 per neighbour

Will a two storey extension add value to my house?

If space is the reason you want to extend your home, look at local houses with the footprint your home will have after the extension. Adding an extension may cost more than the value it will add to the property in the short-term. But yet, it can still work out as much less expensive than moving to a larger property. Remember to factor in estate agent fees, legal fees, Stamp Duty and removals fees if moving is an option.

Properties are generally valued on the basis of price per m². To get an idea of local property values, find several properties that are similar to what you propose to build. Then divide the asking or sale price by the area of the property. This will give you an average value per m².

If you compare this with the average cost per m² of your extension, you can work out whether your proposals will increase the value of your property. Be aware that there is a limit to how much value you can add to your home, known as the ceiling value.




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