Hi all:

Asked this before but didn't get a reply that specifically addressed
the question so I thought I'd try again.

I'm putting up fiberglass batts in a flat roof, i.e., the ceiling is
removed so I'm working inside the house. The roof joists are nominal
2 x 10's. The insulation that was there before had been pushed up
into the cavity between joists and the flanges on the faced batts was
stapled to the wide face of the joists, just above the lower edge of
the joists.

My instinct is to staple the flanges on the narrow edge of the joists,
overlapping flanges to create a more secure moisture barrier.

Is one way of doing the stapling better than the other? If so, how
come?

Thanks.

Tom Young

TomYoung wrote:
....
My instinct is to staple the flanges on the narrow edge of the joists,
overlapping flanges to create a more secure moisture barrier.

Is one way of doing the stapling better than the other? If so, how
come?


You already answered your question albeit the difference is minimal.

--

TomYoung wrote:
Hi all:

Asked this before but didn't get a reply that specifically addressed
the question so I thought I'd try again.

I'm putting up fiberglass batts in a flat roof, i.e., the ceiling is
removed so I'm working inside the house. The roof joists are nominal
2 x 10's. The insulation that was there before had been pushed up
into the cavity between joists and the flanges on the faced batts was
stapled to the wide face of the joists, just above the lower edge of
the joists.

My instinct is to staple the flanges on the narrow edge of the joists,
overlapping flanges to create a more secure moisture barrier.

Is one way of doing the stapling better than the other? If so, how
come?

Thanks.

Tom Young
Hi,
Main thing is to keep the air leak(thru any gap) to minimum.
Whatever makes air tight.

Tony Hwang wrote:
TomYoung wrote:
Hi all:

Asked this before but didn't get a reply that specifically addressed
the question so I thought I'd try again.

I'm putting up fiberglass batts in a flat roof, i.e., the ceiling is
removed so I'm working inside the house. The roof joists are nominal
2 x 10's. The insulation that was there before had been pushed up
into the cavity between joists and the flanges on the faced batts was
stapled to the wide face of the joists, just above the lower edge of
the joists.

My instinct is to staple the flanges on the narrow edge of the
joists, overlapping flanges to create a more secure moisture barrier.

Is one way of doing the stapling better than the other? If so, how
come?

Thanks.

Tom Young
Hi,
Main thing is to keep the air leak(thru any gap) to minimum.
Whatever makes air tight.

I'd be tempted to add a layer of plastic before re-installing the ceiling to
really seal it.

Would that meet code?

Bob F wrote:
Tony Hwang wrote:
TomYoung wrote:
Hi all:

Asked this before but didn't get a reply that specifically addressed
the question so I thought I'd try again.

I'm putting up fiberglass batts in a flat roof, i.e., the ceiling is
removed so I'm working inside the house. The roof joists are nominal
2 x 10's. The insulation that was there before had been pushed up
into the cavity between joists and the flanges on the faced batts was
stapled to the wide face of the joists, just above the lower edge of
the joists.

My instinct is to staple the flanges on the narrow edge of the
joists, overlapping flanges to create a more secure moisture barrier.

Is one way of doing the stapling better than the other? If so, how
come?

Thanks.

Tom Young
Hi,
Main thing is to keep the air leak(thru any gap) to minimum.
Whatever makes air tight.

I'd be tempted to add a layer of plastic before re-installing the ceiling to
really seal it.

Would that meet code?


Hi,
Vapor barrier?

Tony Hwang wrote:
Bob F wrote:
Tony Hwang wrote:
TomYoung wrote:
Hi all:

Asked this before but didn't get a reply that specifically
addressed the question so I thought I'd try again.

I'm putting up fiberglass batts in a flat roof, i.e., the ceiling
is removed so I'm working inside the house. The roof joists are
nominal 2 x 10's. The insulation that was there before had been
pushed up into the cavity between joists and the flanges on the
faced batts was stapled to the wide face of the joists, just above
the lower edge of the joists.

My instinct is to staple the flanges on the narrow edge of the
joists, overlapping flanges to create a more secure moisture
barrier. Is one way of doing the stapling better than the other? If so,
how
come?

Thanks.

Tom Young
Hi,
Main thing is to keep the air leak(thru any gap) to minimum.
Whatever makes air tight.

I'd be tempted to add a layer of plastic before re-installing the
ceiling to really seal it.

Would that meet code?


Hi,
Vapor barrier?

Yes. And seal out any potential leaks.

The insulation that was there before had been pushed up into the cavity
between joists and the flanges on the faced batts was
stapled to the wide face of the joists, just above the lower edge of the
joists.

Thats the proper way unless the air space above the batts is vented somehow.
You dont want to create an unvented air space above your batts which might
be the case in a flat roof. If the batts are placed up against the roof
sheathing, you dont have to worry about venting.

Is one way of doing the stapling better than the other? If so, how come?

When they built our home in the AZ desert, they "wired" the R-30 batts up
against the roof sheathing between the web trusses.

On Sep 26, 4:31*pm, TomYoung wrote:
Hi all:

Asked this before but didn't get a reply that specifically addressed
the question so I thought I'd try again.

I'm putting up fiberglass batts in a flat roof, i.e., the ceiling is
removed so I'm working inside the house. *The roof joists are nominal
2 x 10's. *The insulation that was there before had been pushed up
into the cavity between joists and the flanges on the faced batts was
stapled to the wide face of the joists, just above the lower edge of
the joists.

My instinct is to staple the flanges on the narrow edge of the joists,
overlapping flanges to create a more secure moisture barrier.

Is one way of doing the stapling better than the other? *If so, how
come?

Thanks.

Tom Young

You didn't get the answer you wanted so you're asking again? Reread
the replies.

Joe

On Sep 27, 9:08*am, Joe wrote:
On Sep 26, 4:31*pm, TomYoung wrote:



Hi all:

Asked this before but didn't get a reply that specifically addressed
the question so I thought I'd try again.

I'm putting up fiberglass batts in a flat roof, i.e., the ceiling is
removed so I'm working inside the house. *The roof joists are nominal
2 x 10's. *The insulation that was there before had been pushed up
into the cavity between joists and the flanges on the faced batts was
stapled to the wide face of the joists, just above the lower edge of
the joists.

My instinct is to staple the flanges on the narrow edge of the joists,
overlapping flanges to create a more secure moisture barrier.

Is one way of doing the stapling better than the other? *If so, how
come?

Thanks.

Tom Young

You didn't get the answer you wanted so you're asking again? Reread
the replies.

No, I said I didn't get an answer that really addressed my question.
Go read the *one* reply at

http://tinyurl.com/y8bhmqb

and see if you don't agree.

Tom Young