Venting
the top floor by Isa Stralian
The
venting and cooling of a double story house is more complex
than a ground level dwelling.
The
common statement heard made by owners is.... I only want to
ventilate the upper level as the ground level is cool, so that
area doesn't need it!'
well
of course it doesn't need it, it's cool as a consequence of
the heat migrating to the upper level....all the heat absorbed
by the whole house has moved up into the upper level....even
the heat off the downstairs refrigerator coils has moved upstairs.....so
you could say that the upper level has the combined heat load
of the whole house, making the exercise of venting the upper
level more critical.
In
the quest for making our homes more naturally responsive in
maintaining comfort levels, and reducing costs, one need to
apply a little logic and common sense
Electricity
costs are going to go in one of two directions, ......and down
is not one of them.
So
there you are, a high heat load in the upper level and the concept
of cross ventilation isn't working for you.
Cross
ventilation,....has a nice connotation with the promise of what
you're not going to be able to use efficiently because if you
are able to avail yourself of it, it's going to be uncontrollable
and secondly you're introduced to the reality that dust is a
consequence of volume.
No
one told you?....maybe is was something for you to discover,
so back to the real world
Bedrooms
on the top floor are hot, and if the temperature prevails no
one is going to get any sleep and what makes is worse, there's
a cool breeze outside where the temperature is several degrees
cooler.....and none of it is coming inside.
What
to do?....other than rip off the roof.
Unless
you've been able to master the art of blowing air into a bottle.
You're suddenly faced with the reality that the only way you
are going to get the cool air to come inside is to let the hot
air out....and the best way of getting the hot air out is straight
up and out to atmosphere.
So....you
install on large roof ventilator or cupola...not some mickey
mouse product that works on solar power and delude yourself
that you're going to get free power....because you're not...nothing
is 'free'
Nature
provides you with pluses and minus....and it's up to you to
choose those which could benefit you.
If
you were to punch a hole in the bottom of a full water tank
you wouldn't use a pump to take the water out.
So
too the roof, once there's a nice big hole, the heat will come
barrelling out.
That's
the roof space/attic area taken care of....now for the rooms.
A
ceiling vent placed in each of the rooms which will allow the
heat trapped above door heights to escape into the roof space....and
as it's escaping, it draws the cooler air in from outside to
replace it.
Note that I say 'draw' and not 'sucking', I leave that claim
to the flim flam artists
You
can't remove one thing without replacing it with another...even
if it's air.
Like
I said....try blowing air into a bottle!
The
ceiling vent ideally needs to be adjustable, preferably with
a push / pull action, so you can open and close it incrementally.
Whatever you do, I suggest you DO NOT USE A PLASTIC TYPE....they
break easily and at the worst possible time and you have to
replace the whole unit...if you can find one
Condor
manufacture metal ceiling vents or registers which come in two
types, manually operated, using a rod of appropriate length
with a hook, and 12v electrical, with a remote option.
Not
only do you vent the room(s) naturally but you end up with fresher
and cleaner odourless rooms because you are introducing fresh
clean oxygen by removing the waste air.
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