Full Answer
How to repair broken ductwork under concrete slab?
If your ductwork is breaking down under the slab, a coating is not going to do you any good. There are companies that can use thermal imaging cameras to pinpoint "hot spots" in the floor where a duct might be broken, allowing you to cut into the slab at that point and make a repair.
What are the risks of ductwork run in floor slabs?
There we describe concerns with ductwork run in floor slabs in the article above, including risks of air duct collapse that interferes with air flow through the system, water leaks into the in-slab duct system (not a problem unique to transite ducts), and rodent or insect infestations or even mold contamination.
Can you just fill in the air ducts in a slab?
But sure, if a duct runs under a sound, un-cracked slab, you could just fill the duct opening. See "How to Abandon in-slab and other transite asbestos HVAC air ducts" and the accompanying photos in the article above.
Can you put return air ducts under concrete?
Seal ducts and air-handling units Where Radon Gas is Present. Placing any return-air ductwork under the concrete slab is not recommended, since this will tend to draw radon into the ductwork and distribute it around the house.
How do you fix underground ductwork?
0:131:48underground air duct lining & restoration - YouTubeYouTubeStart of suggested clipEnd of suggested clipThey offer a non-destructive. And less intrusive solution that seals and encapsulate s-- existingMoreThey offer a non-destructive. And less intrusive solution that seals and encapsulate s-- existing underground duct systems using a patented process that can repair any amount of damage.
Can duct work be patched?
If you're patching a sheet metal duct, use a power screwdriver to drive a #10 self-tapping sheet metal screw into each corner of the patch. For a fiberboard duct, secure the patch with a strip of foil tape along each side. Finally, run a bead of silicone caulk around the edges of the patch to prevent air leaks.
How much does it cost to reroute duct work?
Rerouting Ductwork: Materials and labor can cost you $35 to $55 per linear foot. The ductwork type, present and future location of ducts, and difficulty of moving them impact costs, while working in hard-to-reach areas increases costs as well.
How do you seal exposed ductwork?
1:053:14How to Seal Exposed Ductwork- DIY Weatherization ... - YouTubeYouTubeStart of suggested clipEnd of suggested clipSo for this we're gonna use water-based duct sealant this is the most common kind it cleans up itMoreSo for this we're gonna use water-based duct sealant this is the most common kind it cleans up it does not off gas any any volatile compounds something to apply it with this is a foam brush.
How do you fix a collapsed air duct?
1:113:36HVAC - Collapsed Return Duct - YouTubeYouTubeStart of suggested clipEnd of suggested clipLiner they're up hide peel back this insulation splice the duct back together work the insulation.MoreLiner they're up hide peel back this insulation splice the duct back together work the insulation.
Can You Use Flex Seal on ductwork?
Flex Seal can be used for ductwork, interior HVAC walls, wood, concrete, metal, etc.
Can I replace ductwork myself?
Ductwork: Choose Your Installer Wisely It is possible to install HVAC ductwork yourself, but it will require research and willingness to pay attention to detail. Be sure to educate yourself on the intricacies of the work so that you can be sure that you do not inhibit the airflow.
Is replacing ductwork worth it?
Yes, and Here's Why. Ductwork is a vital component of your home's comfort, air quality, and energy consumption. You should replace old ductwork as soon as possible to maintain the performance of your HVAC.
Do you have to open walls to replace ductwork?
0:363:18Should we need to tear open walls and ceilings to replace ductwork?YouTubeStart of suggested clipEnd of suggested clipThe only fix is to tear open the walls and the ceiling. To get at that duct and replace it what say.MoreThe only fix is to tear open the walls and the ceiling. To get at that duct and replace it what say. You. If it's sweating. And it's what it is if it's sweating.
Can I use silicone to seal ductwork?
Sealing duct joints is a DIY project. It's not only easy—it's cheap! Simply buy aluminum-colored silicone caulk and caulk every joint in rectangular ductwork (clean the joints first with a household spray cleaner and a rag to remove dust). Use the caulk to seal around the take-off boots to each branch run.
How do you seal exterior ductwork?
0:1013:28Rooftop Two-Part Foil Mastic Instructional Video - YouTubeYouTubeStart of suggested clipEnd of suggested clipYou could either be the iron grip 601 the versa grip 181 or the spray seal as of course you knowMoreYou could either be the iron grip 601 the versa grip 181 or the spray seal as of course you know this goes on with a spray.
Is duct sealing worth it?
If you have leaky ducts, duct sealing is definitely worth it because it leads to benefits such as: Increased energy efficiency. Improved indoor comfort. Healthier air quality.
How to inspect in-slab ductwork?
Inspect in-slab ductwork first through the floor registers (above left) and better, using a good light or mirrors or a camera system such as the Chim-Scan or plumbing drain camera. The mud in the air duct shown above confirmed a history of building flooding that sent flood waters inside the HVAC duct system.
What are the hazards of in-slab ductwork?
Air quality hazards of in-slab duct systems include rodent infestations in ductwork, dirt and debris accumulation which then is returned to the building indoor air or that serves as a breeding ground for pathogens, radon gas hazards, and water leaks into the duct system which can in turn generate a mold or bacterial hazard or can cause softening, collapse, and blockage of the in-slab transite pipe duct. All of these are described individually and in greater detail within this article.
Why is air ducting more likely to contain moisture?
Because an air duct routed through a floor slab is more likely to contain moisture from condensation or water from leaks or floods, that moisture, combined with normal organic dust and debris found in ductwork can increase the chances of mold contamination in slab-ductwork.
Is rust in ducts a problem?
But rust in ducts is a problem indicator, showing quite clearly that the duct system has been wet. Dust & normal air duct debris: The chief components of house dust, which will certainly collect within a duct system include fabric fibers and skin cells, often also including starch fragments and other organic debris.
Is rusty ducts a health hazard?
at DUCT DAMAGE, MECHANICAL. Rust flak es from rusty heating or air condition ing ducts themselves are unlikely to be much of a health hazard - these particles are pretty big, not easily airborne, and probably won't be found at high levels in indoor air except in unusual circumstances.
Can you get dirt in HVAC ducts?
Don't panic about dirt or debris in HVAC ducts. It is normal for some dust and debris to collect within the air handling system, though by installing and maintaining air filters at the air return registers you can minimize debris and dirt in the ducts themselves. See details at AIR FILTERS for HVAC SYSTEMS.
Is a floor set on concrete?
Simply stomping on or tapping the floor may suggest that the floor itself is not set directly on concrete, or you may deduce the probable floor construction by inspection of the building exterior (presence of crawl space vents) or building dimensions (first floor is located more than a foot above grade level.
How far does the furnace duct run under the slab?
The furnace is in the lower level and the main duct I'm concerned about runs from the furnace about 20 feet directly under the slab under the living room with 1 terminating register and 2 perpendicular runs of about 8-10 feet. The duct looks like it is 8' X 14".
Why is concrete not monolithic?
By breaking up a slab, fixing ducting or plumbing, and then repairing the rebar and repouring concrete, it's no longer a monolithic unit due to "cold joints" where the old concrete joins the new. Sure, it's done all the time, but it compromises the slab.
Does concrete surround ducts?
When the duct was first installed, the concrete was supposed to completely surround the duct so that even when the galvanized duct rotted, the hole in the concrete was still there. You probably have earth exposed in your duct hole.
Is the R value of ducts in slabs low?
The R- value of the duct in the slab is probably very low. Now may be the time to upgrade your home's heating and cooling system. You should determine a budget and then explore what you could have installed for that price. There are numerous ways to go about it, some being more costly than others.
How To Fix a Slab Foundation
It almost goes without saying that a house is only as strong as its foundation. If you encounter problems with your foundation, especially when it’s a slab foundation, you’ll need to make repairs as soon as possible.
Fixing the pipe
To repair a slab leak, you first have to find the source of the leak. If it’s a hot water leak, you’re going to be focused on fixing the piping underneath the slab. It’s relatively easy to locate the leak source by simply walking around the foundation in bare feet until you can feel the leak. When the leak source is found, mark it with duct tape.
Mud Jacking
Another technique for fixing a slab foundation is called “Mud Jacking.” This method focuses on the source of any subgrade problems, working to support the slab from underneath.
What causes a slab foundation to crack?
What Makes A Slab Foundation Crack? In most cases, it’s water or poor site preparation (If the soil wasn’t compacted thoroughly before the footers were built). Erosion can wash out the soil below the footer, creating uneven settling in the home.
What happens if you bend a concrete slab?
This means one side of the slab will shift or sink, exerting tremendous pressure on the slab. Concrete is not a flexible material; if you try to make it bend or curve, it will crack and break.
How does a slabjack work?
This is accomplished by drilling holes through the concrete slab and injecting a filler material underneath it. The filler material takes up space under the slab and raises it- or jacks it - to the desired height.
Is slabjacking a foolproof solution?
We don’t want to give you the illusion that slabjacking is a fool -proof perfect solution. No solution is perfect, and anyone who tells you otherwise is excessively optimistic or deceitful. But the negatives associated with slabjacking are the same as they would be for other concrete leveling methods.
Does polyurethane foam decay?
Because the “mud” used in mudjacking uses a form of concrete, it is susceptible to break down and decay like any other concrete material. Polyurethane foam does not have this issue. It’s environmentally safe, cures almost instantly, and does not decay.
Can helical piers be fixed?
Sometimes helical piers are a better repair choice in this situation. This is often the case for settling porches, which can be fixed by either slabjacking or piers. But if the issue occurs in an interior room of the home, slabjacking may be the best solution.
Can you inject filler into ductwork?
If your home has a floor based HVAC system, there is a possibility of injecting the filler material into the ductwork and causing a blockage. You have to relocate everything out of the room, and completely remove the flooring down to the slab.
