In terraced housing the materials that turn up most often are textured coatings on ceilings and walls, insulating board around fireplaces, airing cupboards and behind boilers, and asbestos cement in outbuildings, garage roofs, gutters and downpipes. That matters in Luton because terraced houses are the largest group there, 29.3% of 85,570 properties, and around 87.2% of the stock predates the 1999 asbestos ban. The next largest group is semi-detached houses at 29.1%, usually with a garage or outbuilding of its own to check. The largest group was built between 1900 and 1939. Property from this period was built before asbestos use peaked, so where asbestos is present it usually arrived with later work: post-war repairs, added textured coatings, new outbuilding roofs and heating upgrades. That later work is common enough in housing of this age that it still needs checking before anything is disturbed. By period, 5.3% were built before 1900, 19.6% between 1919 and 1939 and 12.6% since 2000. None of that tells you whether a particular property contains asbestos; only a survey or a laboratory test can.