How to Hide Ductwork Under Slab | This Old House

In this video, where do you hide the ductwork in a part of a house with no basement, no room in the ceiling and no access in the existing brick walls. Richard Trethewey and Charlie Silva show us the best solution is to bury the ductwork underground. Mechanicals installer James Bouchard shows us the right kind of ductwork to bury and how to do it right, so it lasts for generations.

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About This Old House TV: This Old House is America’s first and most trusted home improvement show. Each season, we renovate two different historic homes—one step at a time—featuring quality craftsmanship and the latest in modern technology. We demystify home improvement and provide ideas and information so, whether you are doing it yourself or hiring out contractors, you’ll know the right way to do things or the questions to ask. Our experts including general contractor Tom Silva, plumbing and heating expert Richard Trethewey, landscape contractor Jenn Nawada, master carpenter Norm Abram, and host Kevin O’Connor give you the tools you need to protect and preserve your greatest investment—your home.

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How to Hide Ductwork Under Slab | This Old House

[ljensen]

Imagine how many artifacts these guys find in a day! Cool. Looks like hard work!

[bobnomura]

This is the craziest thing I ever saw.

[max-zlvm]

BE AWARE IF ANY RADON IN THE SOIL BEFORE YOU BURY RETURN DUCTS. return ducts in radon laden soil can be a nightmare for treatment later on.

[kylefowler]

You just know the interior decorator is going to hate where every floor register is. "I have the perfect sectional couch for the room but the floor vent is in the way!" Rinse and repeat for every room

[stutter]

ducting under your slab is pretty artistic tbh

[ricoludovici]

40+ years ago, our HVAC contractor installed metal duct with a factory installed PVC membrane that was approved for direct burial in dirt. Recently we have Blue-Duct PVC that is also approved for direct burial and carries a 10 year warranty. Between the over-excavation of the trench and the cost of those froth-packs, I don't see any savings using standard spiral duct and foam. But hey, it's their business. Just saying that is not the only way to do it.

[peterjanis]

Jeez all that money to do all that. just go radiant heat and mini splits and call it a day

[snomass]

Ductwork under slab is insane and expensive.

[waterloggeduprising]

Why wasn’t a split-ductless system used?

[tenin]

i love how technology has evolved to where fiberglass was once the king for everything now we have a new one. It made me think of a mowing channel that uses Ridge Right handles to turn your shovel into a better tool. just cool upgrades that weren't really around but now are.

[Soccerloumike]

😂😂😂. 4:10😂😂😂 Famous last words of a fool! 🤣🤣🤣

[jamesblackwell]

I feel that there was an opportunity missed to a use ducted mini-split system. Oh well, good luck!

[Starship]

We have 3 foot wide pvc tubes under my house in PV Arizona as intakes hvac system

[mikequick]

This has some locations it will work and a lot that it will not. Making the ductwork out of stainless steel would be a plus. Definitely add an access/ sump box to this. I have done jobs abandoning this kind of ductwork. A ventilated drain system under the ductwork would be a plus also, since you cant get back to it.

[ronbennett]

Crawl space would have made more sense. Or if drainage / soil doesn't allow for that, then from above, which is what contractors originally recommended. HVAC in the slab will be problematic in the future. All that foam is worrisome too. Hopefully it holds up over time. Presumably foam has been well tested, but would like to see real world results after many years.

[greggoldman]

Bigger question…why the duct and radiant? They have all the floor up, so why not radiant in all the rooms? Cleaner, no noise heat.

[TheRealJonahWicky]

I miss the full episodes. Why just the shorts now?

[mhods]

The bits of dirt and debris in the duct work that have now been sealed away for eternity hurt my soul.

[rustybeatty]

Mini splits AC/Heater would have been a better option because you wouldn't have to do anything special with the foundation about three of them would have worked fine running on 120 volt.

[debluetailfly]

Sad to see houses from 1800s left abandoned to rot away while some piece of junk from 1960 gets all sorts of money spent on it.