Installing trunk line inside the mobile home

[alternative]

Once the general laughter has stopped , I have a few questions with regard to installing ductwork inside the home - not attic, not below floor boards.

We live in a double wide; one half is sort of all open. It would allow me on this half to run a trunk line on the joining wall where it meets the ceiling.
On that side, the registers would be attached directly to the trunk line, on the other half of the home I would have to cut through both sheet rock panels and insert an "extender" before attaching registers.
In other words, my air flow would be similar to an attic system, just all in a straight line in the center of the mobile home.

My questions now:
Do you think this is feasible?
Would the trunk line have to be tapered?
Would conversations/noise carry to adjoining rooms with so many registers on one line?

Any suggestions, info or constructive criticism is much appreciated.

Thank you!

[flcruising]

Any mechanical engineer with tell you this is the most energy efficient method of distributing conditioned air in any building. But to me it seems like alot of trouble and cost to retrofit into an existing manufactured home. Can I first ask why you think it necessary?

[alternative]

Hello Aaron,

Thank you for responding.

We are looking at replacing the existing ductwork and AC/heater units in the near future. Our doublewide is almost 15 years old and was new when purchased. However, it was either manufactured on a Monday morning, when everybody was still groggy from the weekend or on a Friday afternoon, when everybody had mentally already switched off.

The two trunk lines have flex hoses going to the outside walls; our registers are below the windows, flush with the floor.
Over the years I've been able to extract mice droppings and insulation material and other dirt with a vacuum cleaner flex hose, but of course not from the trunk line. Now we are at a point where you can feel holes and cold air coming in when you run your arm inside.

Nobody will clean our type of duct work. In order to find ALL holes in the flex hoses and other mismatched joints, we would have to remove all of the black sheet and insulation material underneath the doublewide - overwhelming task, can't do it, can't afford to have "professionals" do it for us.

An inside trunk line would have the following plus points for me:
a) costs
b) cleaning (possible through registers with vac hose)
c) no insulation necessary
d) no rust (previously water heater broke and flooded duct work)
e) no pests
f) no loss of heating/cooling

Do you now have some pointers for me? What would I have to consider that I'm maybe not aware of? Any help would be greatly appreciated.

Karin

[flcruising]

Are going to remove the old ductwork, or would you just leave the register covers but block off the ducts?

1. Do you have the location for the air handler figured out?

2. What kind of duct material? Spiral metal is expensive.

3. Straight runs are obviously the best, but what if you run into wall studs? Would you open the wall and install blocking where studs need to be cut?

4. Does your whole house have vaulted ceilings? If not, how would you get air to the rooms that aren't...with hidden ducts and ceiling registers?

5. Ductwork must be hung. Insulated metal is heavy. Your roof structure may not hold the required weight.

6. Uninsulated metal ducts transfer noises easily. Especially between rooms like you mentioned.

7. The center of the room is not the best location for discharging heated/cooled air. Exterior walls are best. You may want to look into a 'high velocity' setup to blow across the ceiling towards to outside walls. The plus(+) is they use much smaller distribution ducts. The minus(-) is they are noisy and drafty from the faster air speeds.

Ok, I think that's all I've got to throw out there for now. Just some things to consider.

[alternative]

Thank you so much, Aaron. This helps us a lot and gives us plenty to think about.

Karin

[Yanita]

Hi,

Another thought, all heating ducts are run adjacent to plumbing lines, this helps prevent freezing of the lines. Do you live in a cold weather climate?

Yanita

[Robert]

Hi,

Best thing would be to get someone who has hvac experience with installing the systems and ductwork and go from there.


They don't have to be hung necessarially.


The outside walls are not always best for supply registers.

You would also need to consider the water pipes if anywhere where temps get below freezing as Yanita stated.


Thanks,
Robert