Why aren't foundation wall duct openings wider?!

joshoc · 07-07-2012, 08:09 PM

Apparently the 32 inch wide opening in the cinder block foundation wall of our house is not wide enough for the supply and return air ducts.

The width of the supply and return OPENINGS on the HVAC UNIT, plus the space between the openings is significantly more than 32 inches.

I found out today that the flexible return air duct is about half blocked by protrusion of the foundation wall into its path, because the duct has to veer over so much to attach to the HVAC unit after it passes through the wall.

Why don't they build wider openings in the foundation wall for the air ducts? The openings in the HVAC unit where the ducts attach are not directly side by side, they have space between them, making the unit much wider than the opening in the foundation wall.

The picture I attached is standing in the grass looking into the return duct with the left side panel of the unit removed. The blocked part is solid cinder block - I cannot push the duct open any more than it is.

Thanks,
Josh O.
Nashville, TN

joecaption · 07-07-2012, 08:14 PM

Someone was just a lazy dumb as*.
The is no reason it can not be fixed to make it right.

**beenthere** · 07-08-2012, 07:43 AM

That is an installer not doing his job right.

ben's plumbing · 07-08-2012, 10:45 PM

yep lazy installer.....

joshoc · 07-09-2012, 07:30 PM

But I mean, does the home builder have to make the opening in the cinder block foundation wall meet some minimum width? (The opening that the supply and return air ducts pass through.)

This duct wouldn't be blocked if the home builder had just made the opening in the wall wider.

**beenthere** · 07-09-2012, 07:33 PM

It was probably the HVAC sub that made the hole.

I would suggest posting that pic and some pics from the other side in the building and construction forum. And ask if they think you need a lintel when/if you make the opening bigger.