If I wanted to create a secret mountain hideaway, what are the legal hurdles?

First, you need control over the land. In the UK, many mountain areas are owned by the National Trust, the National Trust for Scotland or national park authorities. However, sufficiently sized private estates come on to the market from time to time.

What’s next?

You will need planning permission for residential use and for any building works. English planning policy advises local authorities to avoid isolated new homes being built in the countryside unless they would be of exceptional quality or enhance the natural setting. Even tighter restrictions apply in national parks and areas of outstanding natural beauty.

Any good news?

Outside of conservation areas, in most of England up to 450 sq metres of farm buildings can be converted to dwellings without planning permission. Scottish policy encourages the provision of huts for intermittent recreational occupation, and Wales offers possibilities for environment-friendly projects.

What about power?

Life may be easier if you might get you go “off-grid”. For a small-scale retreat, you might get by with a wood-burning stove, solar power and a battery-fed LED lighting system. For the more ambitious — again, subject to planning permission — you could construct a biomass-fed combined heat and power plant to deliver electricity, heating and cooling.

And if I go underground?

Underground hideaways would not escape the planning system. Subterranean space (much like Kensington super-basements) requires planning permission, and if you carry out works without it, the law has recently changed so that your development will no longer be free from enforcement after four years. It could mean the removal of the unauthorised works if it is found that you deliberately hid what you were doing from the authorities.

Simon Ricketts is a partner at King & Wood Mallesons

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