best way to fit ducting to Ceiling Fan

suicra05

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Hi,

I am replacing a 4" extractor fan in the ceiling of a bathroom. The last one was damaged due to water (condensation) coming into the fan from the ducting in the attic. This ducting is positioned almost vertically for 3 feet and then goes into a horizontal pipe which eventually goes out the roof via a roof tile.
I bought a new fan and in the instructions it mentions about installing a condensation trap if the ducting is been installed above the fan. Will this prevent the water/condensation coming back down into the fan?
Another alternative is I could get new ducting and run it across some of the attic floor. Then I could leave it open into the attic. Is this ok or would it build up moisture/dampness in the attic?

Any suggestions would be appreciated.
 
Don't leave it open to the attic as it will form condensation within the attic and give you bigger problems.

A condensation trap is the best route to go. Also insulating around the duct in the attic should help as the level of condensation would be reduced.
 
Don't leave it open to the attic as it will form condensation within the attic and give you bigger problems.

A condensation trap is the best route to go. Also insulating around the duct in the attic should help as the level of condensation would be reduced.


+1. Good advice there. Venting into the attic could rot of your roof timbers.
 
Hi,

I am replacing a 4" extractor fan in the ceiling of a bathroom. The last one was damaged due to water (condensation) coming into the fan from the ducting in the attic. This ducting is positioned almost vertically for 3 feet and then goes into a horizontal pipe which eventually goes out the roof via a roof tile.
I bought a new fan and in the instructions it mentions about installing a condensation trap if the ducting is been installed above the fan. Will this prevent the water/condensation coming back down into the fan?
Another alternative is I could get new ducting and run it across some of the attic floor. Then I could leave it open into the attic. Is this ok or would it build up moisture/dampness in the attic?

Any suggestions would be appreciated.

Did you match the fans cfm to the volume of the room?
To do this you multiply height x width x length of room and this gives you volume of room.Your fan needs to flow this volume or more for it to be effective for the size of room.

Use insulated flexible fan ducting for your ducting.You can buy it in 10 20 and 50 meter lengths and you cut to suit the size you need.
Run the ducting from the fan out to a soffit vent in your attic.
Also install an anti-backdraught flap and a plastic moisture trap at some point along the ducting.You can also use moisture proof duct tape to make an airtght seal at the ducting joins.

If you are running the fan off the lights then you will need to install and wire an isolation switch for the fan,so that you can safely work on the fan when you need to service it.You need a certified electrician to do this work as it will have to be certified under safe electric rules and its also the law now.

Go out to ATC on Broomhill Drive in Tallaght and have a look around their showrooms.They sell all types of fans,ducting and fittings for domestic and commercial ventilation projects.
I bought all the fans and ducting for our house off them.

http://www.atc.ie/heating_ventilation/home.asp

[broken link removed]
 
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