ShingleHitter, what’s the slope of your house & where do you live?
If you’re really wanting to gto big time on the vapor barrier, look into a product like Gorilla Guard or some other top shelf product. Here in Texas, it costs about 2x the price of ‘regular’ 30 # felt. FYI, CertainTeed has a 30 # felt that goes 4 squares & from Roofing Supply Group, it’s within $ 2.00 of the price of a 2 square roll of Atlas 30 #.
You can also add extra ice & water shield to the areas where ‘most’ houses don’t get them, which isn’t to say that you are guaranteed to get a leak in these areas, but it’s like driving a Mercedes vs. a Bike – they’ll both get you to work, but one is a bit better in case you have adverse weather (& they both have the potential for making you work harder to get to the finish line). Some of these areas we don’t typically add an Ice & Water is against wall to roof joints, valleys, exposed eaves (outside of the attic heated spaces), across hip tips, along rakes… this can be added in full to all these areas or pick & choose what you want. A LOT of these choices are location specific, i.e. where YOU are based… up North, most of these spots are standard considerations.
If this is an estimate you’re working off of, do you have Starter Strip specificed on the quote or is the installer going to use the “3 Tab Flipped” method? What about metal drip edge? I’m partial to the DL Drip Edge variety. These are two other areas that you can do an improvement over the ‘minimum’ standards.
Write back if you have other questions or comments.