Monday, April 25, 2022

Removing a Bad-Idea Whole House Fan

Here is the beginning of another story of turning neglected and dangerous attic space into something efficient, beautiful and wonderfully useful. In this beginning, we discovered that the attic was stinky in dry and cold conditions, November 2021. Blame this on a dead whole-house fan, and two bath fans not directed through-roof.

This is the attic before improvement, standing with good headroom just beyond a second-floor hallway access with a covering of bare drywall.  Floor framing is 2x8 with fairly-regular @24" spacing. House well-built in 1982.

Getting around in the attic was risky walking a plank, as with a shaky length of 2x8 leading to the whole-house fan, that intermittently was "winter-weatherized" by tossing-on a piece of R11 kraft-faced fiberglass insulation.

More often than not, there is nothing to grab if you lose balance.

The whole-house fan shutters were leaky all-around. 

From below, shutters of the dead fan were tolerated as interesting in a grand stairwell ceiling.

Here are barely-safe work conditions with an installed attic ladder. I have good lighting and connection to house power. Remove the fan and temporarily cover the opening.

A careful patching plan is needed where working over a stairwell.

The tilt-in patch was partially secured with reach-out from the steps railing.

To complete the setting of the patch, work from plywood clamped to on-flat 2x4s and the stair railings. Cutting-in the fan thirty or forty years ago, was a lot easier.

Still to do: increase attic ventilation, and dry out the attic.

And here is the finished attic, brightly lighted and clean, well-loaded with stored items, and still with immense space available. Be grateful for headroom afforded with a still-walkable 5:12 roof pitch.

1/2" plywood covers a central rectangle 20 ft by 32 ft. An undecked periphery about 5 ft wide all around is the preferred zone for wiring and fans. New bath fans are served by new short steel ducts directed through-roof. Want R49 periphery insulation to tuck in and be slightly thicker than the R49 decked area.

1 comment:

g1x4 said...

Phil, I always learn something on your blog. Thank you for the great explanation and accompanying pictures. Never would I install a whole house fan in my home.