When a freelancer works from home he should notify  it to Hacienda, along with the area of the house that is used for the business and the percentage that this represents of the total if he is going to deduct expenses of utility bills and house related costs. 

Normally this will be one or two rooms so a percentage of 20%-40% will be accepted without inquiring more.

In case that you are renting this might be a problem because renting for housing does not have IVA while renting for business proposes does. This means that you need to speak with the owner to produce two different invoices; one for housing without IVA, and one for the business use, with IVA and retentions. 

This is normally a hassle for the owner who from that moment on will have the obligation to collect IVA and makes his quarterly payments. For this reason many people rarely inform of this. 

However having a place from which to work is a logical requisite in most activities with the exceptions, perhaps, of taxi drivers, sale persons, transport business, and the like.

It is certainly necessary to notify that you work from home, with the associated obligations, if you are going to deduct house related expense.

In some cases, when applying for European VAT number Hacienda will request to prove the means used to do business, including the notification of the work place. 

An acceptable option for many can be the using of the services of a co-working area. These places provide a business address along with some other services that can represent a way around the obligation to notify your home address if it is not doable obtaining a separate invoice for the business area. 

.