Chronic subdural haematomas are prone to recollect, increasing the risk of further complications and death. Burr hole evacuation followed by continuous irrigation of a Ringer solution into the remaining subdural cavity, allows remaining blood to be washed out and the brain to re-expand. This technique was compared with burr hole evacuation either without or with a passive drainage and craniotomy, respectively. Reformation of haematomas after continuous irrigation occurred in 2.6% (2/77); more than a twelve (32.6%; 15/46) and a nine (23.8%; 5/21) times rate reduction compared to burr hole evacuation without and with passive drainage, respectively. Compared to the craniotomy results, the rate dropped seventeen times (44.4%; 4/9). Expect from the two rebleedings in 77 haematomas operated on through burr holes followed by irrigation, all patients recovered including nine recurrent haematomas re-operated on by this method. Recurrent haematomas operated on through burr hole evacuation alone or with insertion of a passive drainage, recollected in 50% (2/4) and 33.3% (2/6). Similar rate after craniotomies was 11.1% (1/9). Neither infections nor deaths followed burr hole evacuation combined with continuous irrigation, whereas 5.3% (2/38) and 5.9% (1/17) suffered from empyema after burr hole evacuation alone or combined with a passive drainage, respectively. Five (9.1%) of these 55 patients died either from empyemas (three) or rebleedings (two). Recurrent haematomas evacuated through a craniotomy had no complications from infections. Compared to other methods, continuous irrigation reduces the need for re-operation significantly by preventing haematoma recurrence and empyema formation. Contrary to other surgical techniques, haematoma recurrence after second time surgery did not occur.