My house was built in the mid-1960’s. Attic insulation is limited to thin kraft paper faced fiberglass batts. They are not close to the height of the joists. I would like to add insulation, but would prefer to avoid loose “blown-in.” Could new bats to added to the old? if “yes,” should they be faced or unfaced, and would it matter whether they are fiberglass or mineral wool?
Discussion Forum
Discussion Forum
Up Next
Video Shorts
Featured Story
This time-tested installation method for flangeless windows ensures smooth operation and provides air, water, and vapor control.
Featured Video
Highlights
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Replies
Unfaced fiberglass or mineral wool will be fine. Lay tight between joists, and more on top at right angles.
It may be worth your time to seal up any penetrations in the ceiling before you get started.
It also is worth considering removing the old stuff before you start, vacuuming out all the dead bugs, reroofing debris, and 60 years of dust and dirt.
This would allow for close inspection of wiring for any rodent damage, and let you do a better job of sealing up the air leaks you likely have plenty of.
Vapor barrier use depends on your location. ventilation of the attic to the outside is also worth reviewing as you do these improvements.
I agree with uncle Mike. Get rid of the old insulation, seal electrical boxes, vacuum. Remember the air in your attic bleeds into the air you breathe in your house. Don’t block the airflow from your soffit vents
If you're looking to add insulation to your attic, it's possible to install new batts on top of the existing ones. However, it's important to ensure proper ventilation and avoid compressing the insulation. Whether you choose faced or unfaced batts depends on whether you need a vapor barrier. Fiberglass and mineral wool are both good options, but mineral wool tends to have better fire resistance and soundproofing properties. Consider consulting with a professional to determine the best choice for your specific needs.
I would replace it. My home is 1960s. I had birds in my attic and had it remediated. These guys told me overall the insulation was good and where previous owners added more. So this guy added more in a few spots. But I was still disgusted by bird poop and dead birds. I got a quote for spray foam and it was $15k. Not everything lasts forever, especially anything in a home over 50 years.
Would anyone recommend spray foaming or using the insulating foam boards for your gable ends? I have a colonial 2 story and just curious to see if it can help my 1st story being cool and the 2nd story being hot. I am currently around an r50 w/ bat in the ceiling and was told i have enough ventilation. A/C replaced 2 years ago
Even with enough insulation, the second floor will be warmer in summer than the first.
If you have a single forced air system, see if you have dedicated ducts to the second floor. (very common)
If so, you can seasonally balance them, or get some active controls to split up into zones.
A good HVAC firm should be able to help.
Insulating the gable end between the vented attic space and the outside is not likely to get you much if any benefit.