On Apr 23, 6:07*pm, wrote:
I assumed it was to allow for expansion/contraction due to temperature
changes, which is why I was concerned about glueing down a new roof.

I suppose I could do a test: mark a few points and measure between
them at different temps.

Now another question...Can/should I use exterior plywood for the
underlayment instead of the [current] Iso-Board?

On Apr 23, 6:45*pm, Big_Jake wrote:



You have a real oddball there, Mike. *Typically flat roofs are done in
bitumen (torch-down), EPDM (rubber), or tar & gravel. *Rubber roofs
typically have a service life of around 40 years, glued down, in all
sorts of weather. *Temperatures should not be an issue, but uplift can
be, depending on the size of the roof.

JK- Hide quoted text -

- Show quoted text -

Look into a rubber roof it is melted in place, or if your flat roof is
in a high heating area like Zone 6 or less , consider FOAM roofing of
up to 7 inches, I am considering it. Many flat roof construction has
no insulation in my area, heat loss is maybe 40% up and out an
uninsulated roof for me thats $6000+ a year. Think about cutting your
bill 20-30%

Well, I'm fairly certain the current roof is rubber (black, stretchy,
kinda smells on a hot day, and marks up my bare hands). And what I'm
considering is WeatherBond (EPDM), which is also rubber. I'm not sure
I have much heating loss throug the roof, as the roof joists contain
fiberglass batts.

I am considering the white EPDM, though, since that black just soaks
up the heat in summer.

On Apr 23, 7:35*pm, ransley wrote:
Look into a rubber roof it is melted in place, or if your flat roof is
in a high heating area like Zone 6 or less , consider FOAM roofing of
up to 7 inches, I am considering it. Many flat roof construction has
no insulation in my area, heat loss is maybe 40% up and out an
uninsulated roof *for me thats $6000+ a year. Think about cutting your
bill 20-30%- Hide quoted text -

On Apr 23, 7:25 pm, wrote:
Well, I'm fairly certain the current roof is rubber (black, stretchy,
kinda smells on a hot day, and marks up my bare hands). And what I'm
considering is WeatherBond (EPDM), which is also rubber. I'm not sure
I have much heating loss throug the roof, as the roof joists contain
fiberglass batts.

I am considering the white EPDM, though, since that black just soaks
up the heat in summer.

On Apr 23, 7:35 pm, ransley wrote:

Look into a rubber roof it is melted in place, or if your flat roof is
in a high heating area like Zone 6 or less , consider FOAM roofing of
up to 7 inches, I am considering it. Many flat roof construction has
no insulation in my area, heat loss is maybe 40% up and out an
uninsulated roof for me thats $6000+ a year. Think about cutting your
bill 20-30%- Hide quoted text -

A "rubber" roof that is melted in place is likely a bitumen "torch-
down" roof, which typically only has a life of 20 years or so. EPDM
isn't generally glued directly to plywood. There is a "chipboard"
that is used as underlayment for it, as plywood could have splinters
big enough to cause issues with rubber.

The "iso" board is likely very high in R-value, usually R5 to R7.5 per
inch.

JK