Adding a drop ceiling under a cathedral ceiling ; insulate all the way up ? Do I need a vapor barrier at the roof ?
 

Normal commercial lay in ceilings have the insulation on the
ceiling tile. You can buy it as 2x4 batts, faced or unfaced.
Typical would be 6" faced with the VB against the tile (toward the
conditioned space).

--
______________________________
Keep the whole world singing . . . .
DanG (remove the sevens)




" wrote in message
...
Ive put in a layin 2x4' tile ceiling under what was a
cathedral
ceiling for my 24x16' living room . The heat gain to the living
room
was cut dramatically last summer here in Florida . I have a
space
above the drop ceiling about 3.5' feet in the center tapering
down as
you move away from center . Is it absolutely imperative that I
insulate (using batt insulation) the entire space above up to
the
underside of the roof ? And, must i put in a vapor barrier of
some
sort at the underside of the roof ? Your thoughts
appreciated.
Thanks.

Adding a drop ceiling under a cathedral ceiling ; insulate all theway up ? Do I need a vapor barrier at the roof ?
 

Ive put in a layin 2x4' tile ceiling under what was a cathedral
ceiling for my 24x16' living room . The heat gain to the living room
was cut dramatically last summer here in Florida . I have a space
above the drop ceiling about 3.5' feet in the center tapering down as
you move away from center . Is it absolutely imperative that I
insulate (using batt insulation) the entire space above up to the
underside of the roof ? And, must i put in a vapor barrier of some
sort at the underside of the roof ? Your thoughts appreciated.
Thanks.

Adding a drop ceiling under a cathedral ceiling ; insulate allthe way up ? Do I need a vapor barrier at the roof ?
 

On Dec 5, 7:20*am, " wrote:
Ive put in a layin 2x4' *tile ceiling *under what was a cathedral
ceiling for my 24x16' living room . *The heat gain to the living room
was cut dramatically last summer here in Florida . *I have a space
above the drop ceiling *about 3.5' feet in the center tapering down as
you move away from center . *Is it absolutely imperative that I
insulate (using batt insulation) *the entire space above up to the
underside of the roof ? And, must i put in a vapor barrier of some
sort at the underside of the roof *? * Your thoughts appreciated.
Thanks.

Vapor barrier goes on the warm side of the framing, erto, it shoul dbe
udner your 2x4' tile. No need to go all the way up with insulation, 9"
should be enough.

dunno about that dead space you created, a professional might want to
ventilate it somehow.

Harry K

Adding a drop ceiling under a cathedral ceiling ; insulate all the way up ? Do I need a vapor barrier at the roof ?
 

On Sat, 5 Dec 2009 07:20:31 -0800 (PST), "
wrote:

Ive put in a layin 2x4' tile ceiling under what was a cathedral
ceiling for my 24x16' living room . The heat gain to the living room
was cut dramatically last summer here in Florida . I have a space
above the drop ceiling about 3.5' feet in the center tapering down as
you move away from center . Is it absolutely imperative that I
insulate (using batt insulation) the entire space above up to the
underside of the roof ? And, must i put in a vapor barrier of some
sort at the underside of the roof ? Your thoughts appreciated.
Thanks.

Just bear in mind that high temps and moisture up there will shorten
the life of roofing. Make sure there is air circulating from the eaves
to the ridge to help keep roof temps down.

Adding a drop ceiling under a cathedral ceiling ; insulate allthe way up ? Do I need a vapor barrier at the roof ?
 

On Dec 5, 11:46*am, wrote:
On Sat, 5 Dec 2009 07:20:31 -0800 (PST), "

wrote:
Ive put in a layin 2x4' *tile ceiling *under what was a cathedral
ceiling for my 24x16' living room . *The heat gain to the living room
was cut dramatically last summer here in Florida . *I have a space
above the drop ceiling *about 3.5' feet in the center tapering down as
you move away from center . *Is it absolutely imperative that I
insulate (using batt insulation) *the entire space above up to the
underside of the roof ? And, must i put in a vapor barrier of some
culasort at the underside of the roof *? * Your thoughts appreciated..
Thanks.

Just bear in mind that high temps and moisture up there will shorten
the life of roofing. Make sure there is air circulating from the eaves
to the ridge to help keep roof temps down.

Thanks all for the responses. The space I have above this false
ceiling is naturally quite small, so, can i go with a very small fan
to just circulate the air within that space , or is it necessary to be
vented outdoors ? TY.

Adding a drop ceiling under a cathedral ceiling ; insulate all the way up ? Do I need a vapor barrier at the roof ?
 

On Sat, 5 Dec 2009 13:29:27 -0800 (PST), "
wrote:

On Dec 5, 11:46*am, wrote:
On Sat, 5 Dec 2009 07:20:31 -0800 (PST), "

wrote:
Ive put in a layin 2x4' *tile ceiling *under what was a cathedral
ceiling for my 24x16' living room . *The heat gain to the living room
was cut dramatically last summer here in Florida . *I have a space
above the drop ceiling *about 3.5' feet in the center tapering down as
you move away from center . *Is it absolutely imperative that I
insulate (using batt insulation) *the entire space above up to the
underside of the roof ? And, must i put in a vapor barrier of some
culasort at the underside of the roof *? * Your thoughts appreciated.
Thanks.

Just bear in mind that high temps and moisture up there will shorten
the life of roofing. Make sure there is air circulating from the eaves
to the ridge to help keep roof temps down.

Thanks all for the responses. The space I have above this false
ceiling is naturally quite small, so, can i go with a very small fan
to just circulate the air within that space , or is it necessary to be
vented outdoors ? TY.

You need cooler outside air entering at the lowest point and exiting
at the highest point all the way from one end to the other.

A fan just blowing air around inside the space will do nothing except
add the heat of the fan motor.

No fan should be necessary if the roof was constructed properly with
soffit vents and a ridge vent.

Adding a drop ceiling under a cathedral ceiling ; insulate allthe way up ? Do I need a vapor barrier at the roof ?