Claim tax relief for mortgage interest and property costs

I work from home as a remote employee for a Scottish company. My work address is my own flat, which is where I also live. I'm a full time employee (paye) and I do a self assessment every year. I have 5 rooms in my flat and one is used exclusively as my office room. Which means that 20% of my property is used exclusively for work. I have the following questions: 1) Can I claim a part (20%) of the mortgage interests? 2) can I claim a part (20%) of my electricity, gas, phone and broadband costs? 3) can I claim a part (20%) of any work I do in the house that also impact my office, such as roof work? 4) can I claim things I buy exclusively for work? Such as a new computer Thanks

Hi luciano.ferraro,
Yes. Have a look at:
Expenses if you're self-employed
For more details, have a look at the business income manual at BIM40000 onwards:
BIM40000 - Measuring the profits (specific rules & practices) - receipts & deductions: contents
Thank you. 

Hi, I am not self-employed. I am a full time employee. Does that still work? Thanks, Luciano

Hi

No. please refer to guidance at https://www.gov.uk/tax-relief-for-employees/working-at-home

Thank you