How to remove old gas heating ducts?

[theorist83]

Hello there!

Seeking you lovely legends advice on what the best way to seal old heating ducts from underneath once I get under the house and remove it. Can you zip-tie the ducts, use mascite tape or is the best way to leave and try seal from above. 
I want to reduce any bad air coming from the sub-floor and protect against rodents/mice etc.

I have a very old ducted gas heater and around 10x outlets. I'm keen to remove and decomission it (and looking at central air con). 

I want to remove the old ductwork and leave as little there as possible while still keeping it air tight. Any advice from those who might have tackled a similiar situation is very welcome. 

Cheers!

[EricL]

Hello @theorist83 

Welcome to the Bunnings Workshop community. It's sensational to have you join us, and thanks for sharing your question about your gas heating duct.

Before making the attempt, I suggest checking the age of your gas heating ducts. If it is a very old system, it might have an asbestos covering on it which means that you'll need to get a professional to remove your heating ducts. However, if it is a modern set and is only using a thermal wrap you should be able to remove it with no trouble.

I would suggest both approaches and that is to remove the ducting and cover the outlets with the appropriate material. By removing the ducting, you take away the opportunity for vermin to convert the ducting into a nest. covering the outlets prevents them from coming into your house and prevents cold air from coming through.

Let me call on our experienced members @Dave-1 and @Nailbag for their recommendations.

Please take all necessary precautions by wearing personal protection such as gloves, goggles and a mask when working on your project.

If you have any other questions we can help with, please let us know.

Eric

[Nailbag]

Hi @theorist83 

I wasn’t aware there was ever asbestos covered ducting as @EricL mentioned. So definitely rule that out first. 

Provided this isn’t the case, simply cut away the duct tape at the bottom of each outlet boot and remove all the duct work. 

You can then use duct tape fixed double crossed on the boot openings. Then from above, lift off the register/grill and close the flap. 

Also seal off the return air grill by sealing up the opening with even something simple like a sheet of cardboard taped where the pipe was fitted to. 

This will now seal each vent until the system is replaced. 

Nailbag

[Dave-1]

Good Evening @theorist83 

When you say old, how old? I am thinking of fancy grates in the floor old. As @EricL has recomended I would check the old covering for Abspestos embedded material. It will show which path you need to be on.

Any chance of a photo of a vent or paqrt of the system underneath? That way it will show us what type of duct/concertina piping we are thinking of.

Central air con could use the old ducts if its what I am thinking of, large concertina pipe that ends up at an evaporative unit on the roof. Depends on where you are located to what type of air conditioning is best.

Once we know what the type of duct you have it will be easy to recomend how to remove it.

Dave