Bathroom Ventilation: Fan replacement across North America could almost become an industry in itself. A vast number of them aren't doing what they were designed to do.
A word about Bathroom Ventilation; working in this industry, I find that a lot of people just don't take bathroom venting seriously enough. Most people think that putting up a ridiculously small bathroom fan that doesn't cost hardly anything, and improper venting it into the attic, is just fine.
I see this most often when people who are trying to sell their home, and it doesn't have a bathroom fan, and the new buyer is insisting that there is a bathroom fan installed. Then it becomes a matter of anything will do. I think, that in cases like this, the buyer should specify what is acceptable and what is not. (The same with dryer vents, but that's a subject for another post). The idea that the seller can just put in any old thing, and vent it anyway he wants, doesn't sit well with me.
If anyone is going to install a bathroom fan, it should be properly rated for the size of the room, should have an acceptable Sone rating (a scientific unit used to measure perceived loudness), and it should properly vented in accordance with the current building codes. No venting into the attic should be allowed.
Venting into the attic can cause a lot of problems for homeowners, for one the excess humidity can allow mold to build up in the attic and on the roof sheeting and will have to be removed at some later date. A mold build up in the attic, can in some cases, render your home unsaleable. Removing mold from an attic requires specialized equipment and can be costly, it is best to avoid this in the first place. This is where a good home inspector can really earn his/her money.
In addition to this, excess humidity in the attic can be absorbed by the attic insulation and reduce it's insulating factor drastically. Costing you much more to heat your home during the cold season. Excess humidity can also condense on your home's ceiling and cause unsightly water marks on the inside of the room, this can sometimes create the impression that you have a leaky roof. There can also be instances where excess water, cause by poor attic ventilation, will come through the ceiling or wall. Any of these signs can drastically affect your return on investment when it comes to reselling your home.
Some things to consider, when purchasing a bathroom fan, are as follows:
Airflow: The number of cubic feet per minute the fan will displace.
Airflow requirement: This is determined by the size of the room the fan is intended for.
Sone Rating: Sound level emitted by the fan.
Energy efficiency: How much it will cost to operate the fan.
Styling: (Aesthetics) The fan should compliment the room it is intended for.
Lighting or no lighting: Sometimes additional lighting may be required and a fan with a light might be the best way to provide this.
Fan Controls: There are many choices when it comes to fan controls, multi function switches, timer switches, and humidity controlled switches that can automatically help reduce humidity levels in your home.
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