From Longman Dictionary of Contemporary Englishburn down phrasal verb1 BURNif a building burns down or is burned down, it is destroyed by fire She was worried that the house might burn down while they were away.burn something ↔ down The old town hall was burnt down in the 1970s.2 BURNLESSif a fire burns down, the flames become weaker and it produces less heat → burn→ See Verb table
Examples from the Corpus
burn down• Charlene has lived with relatives since her house burned down.• The hotel burnt down in 1990.• Police believe students are responsible for burning down the school.• Her ex-husband threatened to burn the house down with her and the kids inside. 