All stove installations need to conform to Document J Building Regulations and also the manufacturer's own installation instructions. If the two class then the most rigorous course of action is to be followed.
There are many regulations that need to be followed and here are just a few of the most obvious. This is not a complete list, please refer to Doc J for all regulations.
Distance to Combustibles
a) Every make and model of stove has its own minimum distance to combustibles (e.g. wooden beams & surrounds etc). There will be a figure for rear, side and top of stove and all could be different. They will often be greater than you think.
My own stove has the following requirements and as you can see they are quite large figures.
Rear of stove to combustible 850mm
Side of stove to combustible 550mm
Top of stove to combustible 400mm
Here is my own stove and how it was installed to conform. You can see that the oak beam is well above the stove (it is actually 500mm above). To the sides and rear I have high temperature (1000 °C) decorative fireboard. These are even fixed with 1000 °C adhesive! And they look great. No peeling & cracking plaster after a few months.
b) The flue pipe coming out of the stove has its own minimum distance to combustibles taken straight from Document J. Any combustible must be a distance greater than three times the diameter of the flue pipe. Flue pipes are often 6 inch diameter so any combustible must be over 18 inches away. That is an awful long way away.
Here is a 6 inch flue pipe only two inches from a wooden surround. The wood was showing signs of scorching. The stove was re-installed with a stone lintel so no problem with combustibles.
If the combustible is protected by fireboard then the minimum distance reduces to 1.5 times the diameter. The fireboard must not be directly fixed to the combustible but must be installed to leave a 12mm gap for airflow.
This regulation from Document J is often misunderstood and often misquoted.
All stoves above 5kw must have a permanent ventilation to the outside.
Stoves 5kw and below MAY also need a permanent ventilation to the outside depending on the air permeability of the room. So, a small room that is airtight with very good glazing will need a ventilation installing. This may seem to be going against all you have tried to achieve but these are the rules and must be adhered to.
If your house was built after 2008 then permanent ventilation will be required regardless of size of stove.