[french_guy]

Hello

I received my heat bill for January, and it’s quite high
My furnace is old, and on top of it I guess my house needs more insulation in the attic. That last point might be easier to fix right away, and cost less than replacing the furnace
The section of my roof looks like that (see picture)
I know the additional insulation material must not block the vent, and attic baffles should be installed (I will verify if I already have some)
But if there is no baffle already in place, I guess I don’t need them on the left side since I won’t insulate the portion over the porch, so there is no risk to block the soffit vent, right?
Do you see any problem not insulating over the porch?

 

[Nailbags]

No there is no problem with that I would just put some thing to make sure if you go with loose fill that it does not just spill over. I would bring your insulation up to min R-49 and R-60 is the best and does not cost that much more.

 

[french_guy]

Yeah, I am in Michigan, greater Detroit area.....And it's cold right now
So I guess R-60 is the way to go

 

[Gary in WA]

Before you add any, check if all the wiring/plumbing holes/chases are sealed from the walls below. Air-seal the crawlspace/basement holes in plates/sub-floor there also. This will help stop the "stack effect" and loss of heat you already paid for; http://www.wag-aic.org/1999/WAG_99_baker.pdf

http://www.google.com/url?sa=t&source=web&cd=23&ved=0CCUQFjACOBQ&url=http%3A%2F%2Fapps1.eere.energy.gov%2Fbuildings%2Fpublications%2Fpdfs%2Fbuilding_america%2Fba_airsealing_report.pdf&rct=j&q=foam%20board%20in%20attic%20require%20thermal%20barrier%20with%20drywall%20already%20installed%20on%20other%20side%20of%20kneewall&ei=IvqWTveuIKW0sQK3zPzwBA&usg=AFQjCNHwd56o0AxLi8-V03E5cMUmwWATQw&cad=rja

Wind can push drafts...http://www.greenbuildingadvisor.com/wind-can-push-drafts-through-house

Canned foam savings; http://www.ornl.gov/sci/buildings/2012/B11 papers/80_Bibee.pdf

No ice dams, check your ventilation; http://www.brainerdhomeinspection.com/roofve~1.pdf

Gary