Insulating ducting??

[actiongirl5]

Do I need to insulate the ducting coming from my extractor fan if it is fixed over the boards in my loft?

Mandy

 

[DetlefSchmitz]

This is not really an electrical question, but it depends what temperature you have in the loft. If the loft is colder than the bathroom (probably true) then if you don't insulate then the moisture will condense and run back down through the fan.

There are fittings to deal with this I believe (to catch the water running down) but it is probably best to insulate the duct.

 

[bernardgreen]

There are fittings to deal with this I believe (to catch the water running down) but it is probably best to insulate the duct.

Do both. The first few minutes will create condensation until the duct warms up. An un-insulated duct will cool the air inside the duct. Warm air rises and rising air in the duct helps the fan to move air. Cold air descends and works against the fan.

 

[actiongirl5]

Any ideas where I would get insulated ducting from?? Yeah sorry about the miss posting it was followed on from an electrical question about the fan so it did end up in the wrong category.]

Mandy

 

[bernardgreen]

Ordinary ducting wrapped in a layer of fibre glass insulation and a layer of sack cloth or similar to keep the fibre glass in place seems to work very well.

 

[Ben565]

As others have said, if you are extracting warm air through ducting in a cold loft space, the warm air will condense inside the pipe. So insulating it in some way would be a good idea.

I used Domus Thermal insulation for the rigid ducting in my loft space, wasn't that cheap but really easy to fit, insulates the pipe, and looks nice and tidy.

 

[Grenage]

I picked up some insulated aluminium ducting from an e-bay seller, a I only needed 2 metres. I think it cost about £10 including delivery. Failing that, just tape rockwool to ducting you may already have.

Make sure the ducting is angled down towards the exit point, so any condensation can run out.