Basis of Trust Property

Hi,
Are improvement costs on property owned by a trust, in which a beneficiary has lived in, rent free for years, added to basis? I am aware that, in the case of Alfred I. DuPont Testamentary Trust, expenses incurred to maintain the property in which beneficiary was living were not deductible. Does the same rule apply to improvement costs on property owned by Trust?

Just like with a personal residence owned by an individual, major improvements made by the owner of the property will increase the basis of the property.