The Churchcarewebsite has a very useful section on balancing mission and conservation: http://www.churchcare.co.uk/churches.
Over 75% of rural places of worship are listed. A listed building is protected by the Town and Country Planning (Listed Buildings and Conservation Areas) Act 1990.
To find out if your place of worship is listed go to the English Heritage list
Your local planning authority can also provide you with information on the listing grade of your church, the listing description, details of conservation areas and information on any existing tree preservation orders.
And if it is listed, it doesn’t mean that you can’t make changes or enhance your building. After all, church buildings have always been adapted to meet changing liturgical requirements and to reflect social change. It just means that you will have to present good reasons and work sensitively within the particular historical and architectural aspects of the building. The best tools for this are:-
Statements of Significance and Need
Completing Statements of Significance and Need will help you to understand your place of worship, its history and previous changes that have taken place. This is a requirement for any building project that involves a listed place of worship. Taking the time to do this will reveal potential and limits. If your building is listed you may not be able to make all the changes you want or you may have to seek advice on how you can achieve what you want. Most changes will require that you obtain permission. Like for Like repairs and maintenance should not need permission, but it is always best to check.
A Statement of Significance should describe when the various parts of the building were constructed and when notable additions were made to the interior, for instance the pews, the pulpit, organ or stained glass. It should provide a summary of why they are important and the contributions they make to the character of the building.
A Statement of Need should set out the reasons why it is considered that the needs of the parish cannot be met without making changes to the church building and reason why the changes are regarded as necessary to assist the church in its worship and mission. Liturgical requirements will have to be balanced alongside any proposals for the enhancement of the building for easier access and wider use by the community. The Statement should particularly highlight the significance of those parts which are to be altered.
You can find guidance here:
English Heritage: http://www.english-heritage.org.uk/publications/writing-statements-of-significance-for-historic-places-of-worship/
Church of England Statements of significance and need: guidance for parishes: http://www.churchcare.co.uk/churches/guidance-advice/making-changes-to-your-building/changing-your-church/statements-of-significance-need.
The Methodist Church www.methodist.org.uk/ministers-and-office-holders/property/technical-and-conservation/conservation-information-leaflets