I have been asked by a client to work on-site for a period in order to complete a project due to the confidential nature of it.
However, my office is registered at my home address - can I still claim expenses which occur during this period or must I omit them in this instance? For example, must I deduct, say, the amount of energy I use at my office/home for the five days that I am based at the client's site?
FYI: I am based in London, England (UK)
I am not asking if I should bill my client for the amount of expenses incurred; I merely want to know if I need to deduct the amount of energy, etc., used during the period whilst I am working at my client's premises.