Think twice before you clean those air ducts!

I know that just about everyone has heard about companies that clean the air ducts in homes. The typical way to clean the air ducts is to place a round bristle brush about the same inside diameter as the pipe. It is either pushed or pulled through the pipe. Many times it also has a vacuum suction as part of the brush. Then after they have cleaned the duct they come back and spray various anti-bacterial and anti-fungal chemicals to aid in the cleaning of the ducts.


Is it a good idea or is it a bad idea to clean your air ducts?
It depends on what the air ducts are made of! If you have the strong sheet metal air ducts, then it might be a good idea to have a qualified company clean them. The key is a quality company that knows what they are doing!


But, if you have those flexible plastic air ducts that are in the majority of the homes that have been built in the past eight or so years then you might want to rethink having them cleaned. The flex-duct type plastic air ducting is like a sandwich. it is comprised of an inner layer of plastic like sheeting then a layer of fiberglass insulation and then an exterior layer of plastic. Most of the time the inner layer has a wire that is built into it so that the duct will have additional strength and flexibility to help keep the duct from crushing and closing up. This wire also gives the air duct a fan or accordion shape, that traps dirt and dust. The plastic flex- duct can not effectively be cleaned. Most of the time if cleaning is attempted the flex-duct will be damaged.

This is a picture of a damaged duct as see from a floor register on a new construction home that I inspected.


This is the result of an air duct cleaning company cleaning the construction debris out of the air supply ducts. The pink is the fiberglass insulation part of the flex-duct:

We also have fiberglass fiberboard air ducts. This type of air duct can not be cleaned either. The fiberboard has a protective covering that is easily damaged.

We really do not want fiberglass particles floating around in the air we are breathing every day!
So, if you have metal air ducts you can clean them. If you have flexible type of fiberboard air ducts you should not clean them. This type of air duct needs to be replaced and not cleaned.




Scott Patterson, Middle Tennessee Home Inspector
http://www.traceinspections.com/

Does your house have spots?

If your siding, car, fence or any other surfaces around your house have broken out with a rash of black or dark-brown specks that do not want to come off, you are probably at war with something called Artillery fungus.

I have seen this on many homes over the years, but I have noticed a drastic increase in the number of homes that have been "shot"! The following picture is from a home that I just inspected, even the PVC plastic privacy fence had been shot!

The artillery fungus, cannon fungus or shotgun fungus resembles a tiny cream or orange-brown cup with one black egg. The cup is approximately 1/10 of an inch in diameter. Areas of mulch with artillery fungi may appear matted and lighter in color than the surrounding mulch. The fruiting body of this fungus orients itself towards bright surfaces, such as light-colored houses or parked automobiles. The artillery fungus "shoots" its black, sticky spore mass which can be windblown as high as the second story of a house.

After doing some research I think that I have discovered why we are seeing more homes with artillery fungus problems. It looks like the appearance of Artillery fungi has been associated with wood mulch (versus bark mulch) and the increased use of wood products in potting media. Mostly the use of ground-up wood pallets and unused pulp wood and the use of fallen trees from storms that have been ground into mulch .

The best way to limit your exposure is the composting of these products prior to incorporation into media is encouraged to prompt the growth of beneficial antagonistic organisms. Better yet, use only the bagged or prepackaged mulch from a garden center. Bulk mulch (not in bags) tends to be more of a raw material that could contain spores.

Also, the use of gravel mulch, stone, pea gravel, and black plastic next to buildings instead of using wood products will help reduce the problem. If wood products are used, the addition of about 3 cm of fresh mulch to cover old mulch each year may lessen the problem. Use of bark products, rather than wood products, may also lessen the fungal spread.
One word of warning to homeowners wishing to replace house siding splattered by Artillery fungi --- insurance companies may not cover claims of damage due to "molds".

Scott Patterson, Middle Tennessee Home Inspector
http://www.traceinspections.com/