I do not believe you can include the mortgage or the council tax as these are not solely for the business (e.g. if you were not running a business then they would not change).
Regarding your services bills, you need to calculate the proportion of the area of your property that you are using for business and then you can use that percentage of your gas/electric etc (heat,power and light really) as business costs. e.g. if you were using one room of a five room house (not incl kitchen and bathroom) then you could allocate 20% of your bills to the business. Obviously if, for example, you only use gas for cooking then this is not applicable. I was told I could not assign water costs even for washing the van.
Phone call costs can be broken down on a reasonable basis based on proportionate usage.
You can also claim for laundry costs for your work uniforms if you only use them for work.
All your stationery, stamps, printers, ink, small tools (not capital items), advertising costs, professional fees, appropriate proportion of car repairs can be claimed as expenses.
It may be worth you having a look at the HMRC website as they have comprehensive (and sometimes OTT) information available and also check out the business link website that has easy to understand information.
The tax office offers free courses on starting your own business and the tax implications, get on some of those, they are very useful, and you can ask questions (you may not get answers!).
