How to Install a Whole-House Fan | This Old House

all right to get started we want to

remove the plywood on the floor tom I

pulled the insulation out of the day

okay Eric now let me show you how the

fan goes now it'll actually fit right in

between the joist Bay and we are now

located over the center of the hall what

we have to do is we have to build a

chute so we have to close off this end

and this end of the joist Bay so when

the fan is on it will pull the air from

below alright now I cut a couple of two

by tens the width of the Bay drop one

down here I want to make it flush with

the top I'm going to use a 16 penny nail

drive it in now I want to square it up

in the bay take my square hold it

against the joist and the block okay now

on the other side alright now we do the

other end put that block right in the

hole air put it against the line that

I've got ready all right we have some

play in the opening that's perfect now

the fan is gonna sit on top of the

plywood so let's put the plywood back

and we'll cut the hole in the plywood

for the fan

now I know that the two by ten blocking

is about seven and a half inches from

the edge of this plywood so I'm going to

drill a hole about eight and a half

inches in all right now I'm gonna use my

plunge router with a flush cutting bit

that has a bearing on the bottom that

will ride along the inside of the 2 by


now I'm gonna cut the actual ceiling you

collect the dust from down below with a


now this wire right here in the opening

actually feeds the two ceiling lights in

the hall now there's enough play and I

can simply slide it over to the end of

the opening and I'll staple it so we

don't draw any air from under the

insulation we're going to fill this void

or this gap with foam insulation to make

a nice tight seal between the bottom of

the fan and the top of the floor we're

going to stick on some weather stripping

the weather stripping also cuts down on

any vibration the fan might create now

just put the fan in the opening take a

couple screws to hold it into position

so it doesn't move around now Eric

that's a two-speed fan and on high that

will draw 1,600 cubic feet of air out of

your house a minute all of that

exhausted air is going to come into the

attic and it has to have some place to

go some of it will go out the soffit

vent on this side of the house some of

it will go out the soffit vent on that

side of the house and some of it will go

out the ridge vent but a lot of it will

go out these windows on the gable end of

your house

so I'll keep these open all summer long

time that's right Eric you plug the fan

in I'm gonna go attach the grill to the

ceiling sounds good tom

all right your grill is attached now to

activate the fan you simply use this

remote when you push the button the

first thing that happens all the

insulated doors will open once they're

opened all the way then the fan blades

will start now you're going to notice a

big difference in the comfort of your

house but you're really going to notice

the difference in your electrical bill