Originally Posted by k2000lbs (Post 819839)

Hi all,

I own a 1951 built house that is about to go through some major remodel. I am curious on what people think on how I should handle my insulation situation. In my attic currently, I have what can best be described as a thin layer (1-2 inches) of loose fill insulation, topped by rolls of R19 fiberglass insulation. I know that this is not enough, I am well below the minimum of R30 rated for my zone. Another issue with this insualtion setup is that the vapor barrier on the rolls is facing up.

My initial questions are - when adding additional (unfaced) insulation on top of everything, should I completely peel off the facing of the insulation or will cutting strips into the facing allow for enough moisture to pass through? Is it even worth to make either effort or should the faced insulation be completely replaced to eliminate any moisture from being trapped.

Blown in insulation (preferably cellulose) is much easier to install and lays down in the gaps, cracks, etc better and more significantly than roll out insulation.

Yes, you should remove the kraft facing entirely and not just cut slits into it. Removing the batts might be overkill but by the time you are done "modifying" them, still might be easier as well.

Adding a twist to this entire situation is the remodel of the house. Part of the remodel will involve removing the ceiling in certain, but not all, rooms. When this is done, both the loose and rolled insulation will fall through. The loose insulation will be near impossible to use again due to it getting mixed in with construction debris, but is it worth the trouble to re-use the rolls, but with the vapor barrier facing the correction direction? If I do not re-use any insulation, should I go ahead and replace the insulation in the parts of the house where the ceiling is not being removed?

In this application, just remove it entirely and toss it.

The previous owner also added nailed a lot of wood planks to the ceiling joists, I think to make walking around up there easier. Will these planks cause any issues? I am mostly concerned about moisture being trapped.

No, not as long as they are not continuous and air tight.

In the end, insulation will be at least R30 in total, I am just hoping to figure out the best plan to solve both problems of under-insulation and incorrectly facing vapor barrier.

Go for R-50. The delta is cheap in terms of materials and you should shoot for what Energy Star is calling for.

Originally Posted by Windows on Wash (Post 820287)

Be sure to research "Air Sealing" as well. Just adding insulation without first air sealing is only fixing 1/2 of the problem.

Originally Posted by Windows on Wash (Post 823346)

If the floor boards are staggered and the air sealing installer can spray foam under them without having to remove them, they don't need to come out.

Originally Posted by Bob Mariani (Post 823383)

And you are assuming that the under valued R-Value under the floor boards is okay? Why? If you need R-38 why is it okay to reduce the overall value by only having R-19 in this area.

Originally Posted by Windows on Wash (Post 823404)

Not at all. Note that I mentioned if the boards were staggered.

A picture would be more helpful in this application but often times these walking board are scattered and far from continuous. In that scenario, it is quite easy to air seal the top plates and other locations without moving them around and also very easy to blow insulation under them.

After that, the attic of over blown with insulation and the boards do not interrupt the insulation layer and are within the insulation layer.

I guess you might be able to claim that the slightly lesser R-value (1 per inch vs. 3 and change) is a drop but if you are putting in R-50, you should be more than fine.

Keep in mind that removing these boards (even when done carefully) if they are not in requirement of removal can tweak joists and create cracks in the finished ceiling.

Originally Posted by danpik (Post 826567)

Not to be an alarmist but, I would be interested to know what that 2" of loose fill insulation is before I mess with it.