{"id":"roof-built-up","version":"0.1.0","classification":{"uniformat":"B3010"},"names":["Roof, built-up"],"aliases":["BUR","tar and gravel"],"service_life":{"median_years":15,"range_years":[10,20],"range_basis":"source_spread"},"pm_tasks":[],"basis":[{"type":"public_document","life_type":"planning","title":"CNA e-Tool Estimated Useful Life Table","by":"U.S. Department of Housing and Urban Development","url":"https://www.hud.gov/sites/documents/eul_for_cna_e_tool.pdf","page":8,"code":"HUD CNA 3.3.4.2.1","label":"Low slope-Built-up Roof, with gravel finish","years":20,"note":"Same life for family and elderly properties. US multifamily housing. HUD gives 20 years with a gravel finish and 10 without."},{"type":"public_document","life_type":"planning","title":"CNA e-Tool Estimated Useful Life Table","by":"U.S. Department of Housing and Urban Development","url":"https://www.hud.gov/sites/documents/eul_for_cna_e_tool.pdf","page":8,"code":"HUD CNA 3.3.4.2.2","label":"Low slope-Built-up Roof, no mineral or gravel finish","years":10,"note":"Same life for family and elderly properties. US multifamily housing."},{"type":"public_document","life_type":"accounting","title":"Trent Lakes: 5.17 Capital Asset Policy","url":"https://www.trentlakes.ca/media/fjaduus0/517_capital-asset-policy.pdf","page":10,"label":"Roofing - Tar & Gravel","years":15,"note":"Capital asset policy (amortization period). Approved on text check: the label and value were found on the cited page."}],"confidence":{"grade":"C","sample_size":null},"open_questions":["HUD gives planning lives for US multifamily housing; the municipal rows are Ontario accounting lives. Neither is observed replacement data.","No preventive maintenance tasks are sourced yet."],"contributors":["unfinished.one editors"],"last_reviewed":"2026-10-21","canonical_url":"https://unfinished.one/c/roof-built-up","versioned_url":"https://unfinished.one/c/roof-built-up/v/0.1.0","licence":"CC-BY-4.0","citation":"unfinished.one (2026). Roof, built-up, v0.1.0. https://unfinished.one/c/roof-built-up/v/0.1.0"}