How to compress air in the house to check for air leak?

Question

I was told we can turn on the exhaust fan in the toilet to suck out the air, then hold an incense stick to check for leak. How long do we need to turn on the exhaust fan?

Would appreciate if you can share us some other procedure.

Answer 1

you need to have all the exhaust fans on at the same time that you do the test.  In doing so, you create a low pressure zone in the house. the smoke will travel away from the air leak as air from the outside replaces the air exhausted out the fans.

You also need to close up any fire place dampers, doors  and windows etc... to get a better seal, thus a greater difference between the outside / inside pressure.

Hope this helps.