returns using wall cavity - move them to ceiling?

[zork]

It was recommended that we move our returns that are using the wall cavity (between the sheet rock and 2x4s) to the ceiling so they can be properly matched up with the properly sized return duct in the attic.

It is costly to do this and I wanted to know how critical it was to have this done.

We are going to have our ductwork replaced, but this return movement is an extra cost.

Thanks,

Zork

[chillbilly]

You posted that it was recommended. Was it determined that relocating the returns was necessary?
If it is necessary for sizing or other reasons, than you have to absorb the cost. You get what you pay for.

[classical]

Eliminating returns at floor level and only installing them in the ceiling will increase dust in your home.

Having adequate return air capacity and proper supply ductwork are the most critical aspects to having a proper install. Regardless of what equipment you have installed if you have inadequate return or supply ductwork the system will be junk.

Most equipment failures are due to poor airflow and or dirt. Newer more efficient system are much more critical on airflow than any other factor.

You mention having your ductwork replaced what type do you currently have and what type are you having installed. If you have metal with externally wrapped insulation and are replacing it with flex I will scream.

If I were quoting you a system and you needed additional return air for it to function correctly it would not be an option it would be part of the price. If price is an issue than you give up something else so the system will function more efficiently and trouble free for a longer system life.

If you are looking at an Infinity system as you mention in another thread and cheap ductwork and insufficient return is a consequence of purchasing that system buy a less efficient more simple system. A less efficient simpler system installed correctly will be more efficient and provide greater comfort for a longer time than a poorly and incorrectly installed high-end complex system.

[mam123]

I would keep the returns that you have and add a ceiling return if necessary to give extra CFM of return air. Add a media filter or easily accessed filter base to ensure that all of the return air will be filtered.

[davidr]

Originally posted by classical
Eliminating returns at floor level and only installing them in the ceiling will increase dust in your home.

Al,you peaked my interest with this statement.

Would you mind to go into further detail about this?

[Toolpusher]

I'd say the amount of dust will stay the same, But the build up will increase.
Having the r/a low allows the filter to pick it up. Moving them to the ceiling, will show an increase in the build up, not the overall amount.

Only way to increase the amount would be by more movement in the room or area, be it human, animal or air.

[Edited by Toolpusher on 09-18-2005 at 08:41 PM]

[classical]

Toolpusher is correct just a matter of semantics. It would be more precise to say that the homeowner would notice more dust in their home. Dust has weight and when the system shuts off suspended particles fall back to the surface. With floor level grills these heavier particles are swept up to some extent.

I prefer to have 60% of my return capacity in the ceiling and 40% at floor level. This is in Houston I suspect it might be opposite for a cold climate. I also try and have a return in every room except for Kitchen, Utility and bathrooms. For rooms that have very high or vaulted I like one high and one low.

If money were not a concern I would want a return high and low in every room. However if I were going to go to that expense I would just as soon install a SDHV system.

[pstu]

Classical said:
>>Eliminating returns at floor level and only installing them in the ceiling will increase dust in your home.

If this is the case, does it not mean that more dust has been sucked into the equipment?

Also, from what I have heard a fresh air intake can really help the dust problem in some homes. Any comments?

Best of luck -- P.Student

[dash]

Originally posted by zork
It was recommended that we move our returns that are using the wall cavity (between the sheet rock and 2x4s) to the ceiling so they can be properly matched up with the properly sized return duct in the attic.

It is costly to do this and I wanted to know how critical it was to have this done.

We are going to have our ductwork replaced, but this return movement is an extra cost.

Thanks,

Zork

Common problem in our area,the 2X4 space in the wall is ,Too Restrictive,even if the duct to it is properly sized.Change ,in this case,is a good thing.

[amtec services]

Wall retuns like this are prone to pulling air from the unconditioned space. You cannot seal them as easily as exposed ducting. Check to see if your utility company offers rebates on sealing duct systems. Might help to defray the cost. I'd go with the ceiling return.
Amtec

[zork]

Currently we have the plastic wrapped flex ducts that fall apart from UV light hitting it. I think it's either a R-4 or R-6. We are going to have them all replaced with R-8 foil back ducts.

Is there a good way to seal the wall cavity and have it be a useful duct? Or would it be best just to seal them off and go with new ones in the ceiling as I mentioned earlier? Or as "classical" said about 60%/40% and keep the 2 existing returns at the floor level, but seal them from any external air getting in. Then install some new ones in the ceiling?

Currently we have 3 returns, 2 at the floor level and one at the ceiling.

Zork