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Provided that my sponsor owns a house in the UK, are council tax and utility bills enough documents as proof that my sponsor can accommodate me?

No.

GOV.UK provides guidance about documentation to support a visa application. Note in particular All documents must be originals and not photocopies and Section 4:
Section 4: documents you should not send unless specifically requested

This page provides guidance on the types of documents that are not required to consider your application.

• if you are applying as a family/group you do not need to provide multiple copies of the same documents

• bank statements or letters issued more than 1 year before the date of application

• driving licence

• photographs (other than passport photographs required in section 1)

• notarial certificates

• business cards

• hotel bookings

• flight bookings

• photocopies of bank cards

• credit card statements

• certificates relating to leisure activities

• evidence of car ownership

• travel insurance

• sponsor’s utility bills

• sponsor’s council tax bills

• educational certificates (unless specifically listed in section 3)

I have emboldened the two you ask about.

Section 2: other documents you may want to provide – all visitors covers what may strengthen your case. This includes, from sponsors:

where a third party (who is either in the UK or who will be legally in the UK at the time of your visit) is providing financial support to you e.g. a business, a friend or a relative, documents to show they have sufficient resources to support you in addition to themselves and any dependant family should be provided