Composite rent taxation depends on whether building rent and asset or service charges are separable. Composite rent arises when a property owner receives rent for a building together with rent for other assets or services such as furniture, plant and machinery, lifts, security or power backup. If the letting of the building and the other assets or services is separable, the building portion is assessed as house property income and the other portion under business income or income from other sources. If the letting is not separable, the composite receipt is assessed according to the combined letting arrangement.