Double stretched hayracks are, apart to the single stretched hayracks, the most endangered type of hayracks in Slovenia. Therefore, 9 double stretched hay racks were researched, their wood species determined and dendrochronologically dated, age dendrochronologically ascertained, eventual reparations and remakes assessed. Žukovec hayrack from Preska near Dobrnič dates to 1946, it was most likely built in 1947. Markovič hayrack from Dolenje Polje dates back to 1938, it also contains some wood from 18th and 19th century. Pust hayrack from Globodol was built immidiately after 1918. Grandovec hayrack from Artmanja vas near Dobrnič dates back to first half of 18th and second half of 19th century, so we presume that this hayrack was repeatedly renovated. Može hayrack from Dvor cannot be dendrochronologically dated successfully, because of bad preservation of wood and columns. Žagar hayrack from Dolenje Karteljevo was built immediatelly after 1960. Legan hayrack from Korita near Dobrnič dates back to 1939, it was most likely built in 1940. By the number of annual rings it was estimated that the hayrack was built in 1933. Pekolj hayrack from Artmanja vas near Dobrnič dates back to 1943. All the dated hayrack columns are made of oak wood. The results show that, by the year of origination, the double streched hayracks are younger than double hayracks. Due to the nature of the construction they decay very quickly when exposed to weather conditions.