Division 43 (Capital works deductions) refers to the depreciation of the structure of the building, usually objects that are irremovable. Capital Works may also be known as Building Write-Off or Capital Works Allowance. Residential properties built after the 15th of September 1987 are eligible to claim capital works deductions over a 40-year period which will be depreciated as a straight line at 2.5% per annum. When construction costs are unknown, a qualified specialist, such as a Quantity Surveyor, will be responsible for estimating the building.