Heads up to those that consider using regular air compressors.

As a general rule, air compressors that are used for "shop air tools" and paint booths, tire filing etc. DO NOT HAVE BREATHING AIR FILTRATION installed. A big problem with this type of comperssed air is that oil from the compressor will be present in the output air...guess what happens when lungs inhale oil? Sounds like a way to develop breathing problems.

Not trying to rain on the parade here, just want to keep folks from turning blue. There are filtration systems that can be used, search WWGraingers, McMaster Carr and other similar types of industrial equipment suppliers.

Also note that most houses have many sources of air leaks in the rooms that are not immediately obvious, such as the electrical outlets, plumbing standpipes, cracks in the floor / walls / ceiling from the building settling as it ages....sadly the list goes on.

Pressurizing from a bathroom exhaust fan is also problematic due to the looseness of the fan housing construction, need for reliable power source, having to re-arrange the ducting for the fan as most are designed to exhaust a room, not pressurize it, and the fact that many household fans may are only capable of less generating than 100 cubic feet per minute of air volume, usually at very low pressures.

Compressed air tanks (scuba etc.) generally hold less than 200 cubic feet of compressed air, which as noted earlier becomes prohibitive in terms of $ and equipment.

Regards,
Comanche7