How do you identify draughts in the house?

How do you identify draughts in the house?

Here are tips for finding draughts in the house:
Check for rattling or whistling around doors and windows.
Shut a door or window on a $5 note. If you can pull the note out without it dragging, you’re losing energy.
Feel for moving air around doors, windows, electrical and plumbing outlets, fireplaces, vents, exhaust fans, floorboards, architraves, cornices, skirting boards and other areas.
On a windy day move a burning incense stick or mozzie coil around suspected draught areas to see if the smoke moves. If it does you have an air leak.
Check for potential gaps from outside at night when the lights are on inside. If you can see light shining through you need to take action. 
Get a professional to conduct an air-leakage analysis (also known as a blower door test) on your house.