Has anyone blown insulation under a floor?

Old 12-11-15, 08:39 AM
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Has anyone blown insulation under a floor?

I have a walk up attic with a 4x8 t&g sub floor. I would like to get some insulation under the floor. It measures 28' x 28', and I have 2' access on either side. I have seen where a person drilled holes in the floor and used the nozzle to fill his floor cavities and am thinking maybe trying this option if I cannot shove the hose under the floor from the sides. Anyone have any experience with this or advice? Thanks
Old 12-11-15, 02:02 PM
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How wide are these joist?
Reason I ask is far more often then not that attic was never intended for storage and never should have had a floor in the first place.
In VA there should be a bare minimum of R-38 to R-60 of insulation in that attic, that's about 12".
Old 12-13-15, 06:59 AM
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Aside from the structural adversities mentioned, you may encounter perlins between the joists which would make it impossible to send insulation from side to side without a gap. Try sending a fish tape across the span to see if it hits an obstruction. If so, you won't be able to do a complete job.

Unless you are able to add unlofted R38+ to the attic, what you will encounter will be inefficient in the long run.
Old 12-13-15, 03:38 PM
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Why can't you cut a 2' wide section of floor and blow from the middle to both sides?

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