ᐅ Blow-in Insulation – How Much Dust Is Normal?

Hello everyone,

Today, the blown-in insulation was installed as cavity insulation between the rafters in our house. It was quite dusty during the process. We had assumed that this wouldn’t happen and that the insulation material would be applied fairly precisely into the rafter cavities.

Is it normal for it to be this dusty? How can the dust be removed from the house afterwards? The contractor has already vacuumed, but there is probably still a lot of dust on the walls and the membrane, right?

Thank you very much.

I don’t recall any particular dust issues during the process. At that time, the construction progress was not far enough along to have to worry about dust cleaning.

hampshire schrieb:

I don’t recall any particular dust problem during the process. At that time, construction hadn’t progressed enough to really worry about dusting.

Hello Hampshire,

thank you for your message. Are you satisfied with the blown-in insulation?
I was really surprised at how much dust was generated during installation; the carpenter had told me otherwise. Also, the underlay membrane bulges inward by several centimeters (inches) — did you notice the same? Additionally, I found a small hole in the membrane, which makes me question how airtight the whole system is, or if over time the material might leak out and cause dust contamination in the indoor air.

Thank you very much for sharing your experience!

unser_schloss schrieb:

Hello Hampshire,

Thank you for your message. Are you satisfied with the blown-in insulation?
I was really surprised by how much dust there was during installation; the carpenter had told me otherwise. Also, the breathable membrane bulges inward by several centimeters (inches) – is this the case for you as well? Additionally, I found a small hole in the membrane, which makes me doubt how airtight the whole system is, or whether over time the insulation material might leak out and cause dust contamination of the indoor air.

Thank you very much for sharing your experience!

You can seal the hole with a strip of Ampacoll tape; it lasts for centuries...

That shouldn’t bulge…

unser_schloss schrieb:

Are you satisfied with the blown-in insulation?

Yes, the house is clearly well insulated, and there were no particular issues. The holes were sealed as described by @seat88. There is no bulging. Maybe my wall construction is different.