Planning Permission

[Freddytwoshoes]

I have had a timber building in my garden/woodland which my mother and also mother in law stayed while visiting over the last 20 years as its on one level ( no stairs). It has its own septic tank and mains water with electricity connected from main house and private separate driveway. I now use it on a regular basis due to health problems (unable to use stairs in house).
Can I apply to improve existing facilities for my wife and I. We are both in our late seventies.

[Buenchico]

You can apply to do anything you like but the chances of success in your application will depend heavily upon
(a) whether there's already any sort of planning permission in place for the building ; and
(b) the exact nature of the improvements that you're hoping to make. (If they won't substantially alter what's been in place for two decades, you might well stand a very good chance of success. However anything which greatly increases the size of the building, or which clearly changes its purpose, might be likely to come under greater scrutiny).

Planning officials are often willing to give informal advice before you submit (and pay for) a formal planning application, so I suggest contacting your local authority's planning office to see if they can give you any guidance.

[Canary42]

/// Planning officials are often willing to give informal advice ///

Not in my experience - I just asked whether turning the ground floor of my house into a museum stood any chance but they replied that to find out I would need to fill out a planning application and pay several hundred quid to submit it.

But you're right, I do believe some are more customer friendly to the folk who pay their salaries, and less "jobsworth" in their outlook. So give them a call Freddytwoshoes.

[The Builder]

What you describe, Freddy, is likely to be classed as a "granny annexe."
An extension to the main house (it doesn't have to be "attached")

Generally regarded as "Permitted Development"
It's easy to check with your local planning dept. though. It would be worth it, as there are exceptions to PD.
For instance... Listed Building, Conservation Area, Restrictive Covenants etc.

Planning Depts vary a lot even though they should all be using the same hymn sheet ;o(
Some might be reluctant to stick their necks out. In which case they'll ask for an application for a "Certificate of Lawfulness"
There is a fee of course, but the procedure is quite straightforward.
A C of L is just an official acknowledgement that you don't need Planning Permission. Nothing to be afraid of.

More important is compliance with Building Regulations. What you describe is "Notifiable".
For small works such as this, a "Building Notice" is by far the easiest and cheapest way to comply with the Regs.

Go for it ;o)

[bednobs]

if you are disabled, you can apply to have the application fees waived (at least you can here because i've done it)