Insulating exterior walls with no vapor barrier or sheathing...

rush

My house was built in 1915 and I am trying to cut down on heating/cooling costs. The ceiling is insulated, however, the exterior walls currently have no insulation, but they also have no sheating or vapor barrier. The walls are old lap siding which is attached directly to the studs.

From my understanding, if I were to use blown-in insulation, this would create a mold, mildew and rot issue from water seeping behind the siding.

My questions is this: Is there any way that I can insulate the walls safetly without tearing off the interior or exterior walls?

I appreciate any help on this issue.

Thanks!

Wildie

If water were infiltrating your walls, your house would have sustained terminal damage, years ago.
Any moisture problems would originate from inside the house.
This moisture can be limited by painting the inside of interior walls with acrylic paint. It forms a vapor barrier.

I had my 1948 bungolow insulated with blown in cellulose 3 years ago and am pleased with its performance.

jklingel

any way to wrap the house with a water resistant barrier (tyvek, etc) and re-side it? you may well NOT need a vapor barrier, but rather a vapor retarding paint and gasketed sheet rock system. there are special vapor retarding paints that are air barriers but also let the wall breathe (vapor back out) to the inside. insulating with blown cellulose is a good way to go, but you need to stop exterior water penetration and interior AIR movement (hence the vapor barrier/gasketed sheet rock system). true vapor barriers (visqueen, etc) are only needed in real cold places, like zone 7 and 8.

gregzoll

my walls do not have any insulation, other than the bathroom (only because it got renovated this past Spring, and R-13 placed in the stud cavities), but the walls are air tight. At the coldest point last Winter, I did have to raise my thermostat to around 70, but normally keep it at 68. At night, normally 60, but had to raise to 62. This past month, since we have gotten the C/A, we keep the thermostat at 73 when home, and 76 when away, and cycles like it should.

It is about keeping the ceiling at the proper level for insulation (check your area on depth), and making sure that doors and windows are air tight. This year, we also placed Foil faced Foam board in the basement windows and sealed with caulk to stop air infiltration, and have noticed a big difference.

What do your bills look like between last year, and previous years, and how old is your HVAC system? These are also factors to consider, just like doors, windows, and insulation.