0:00
In this video I want to explain a couple of things. First of all, the ducts you see
0:07
here, this one here, and this one here, coming down to floor level, those are
0:14
cold air return ducts, and it's essential that if your home is heated with any
0:21
sort of a forced air heating system, you have to have the cold air return ducts
0:29
the ducts that deliver cold or cool air back to the furnace for reheating, those
0:35
do have to extend down to floor level or near floor level, and that's so that
0:42
there'll be a continuous circulation of air throughout your basement. Without this, you're going to have cold spots. Many basement ventilation systems are
0:55
roughed in so that this duct here is just up here at the ceiling. It's easier
1:03
for installers to do that, and if costs are being cut, then that's where the cold
1:10
air return duct will go. The louver will be up here at the ceiling, and it
1:15
really isn't going to cause a problem for you if it stays there, because the
1:20
cool air is being drawn back into the furnace from up here, and then all the
1:24
air down here is going to remain stagnant, and it'll get kind of warm, but
1:30
not really warm enough. So extending these ducts down to floor level, that's
1:36
key. So that's a good thing. This basement is showing us something that we
1:42
can copy. It's also showing us something that we should not copy, and that's this
1:48
wood frame perimeter walls with fiberglass insulation behind a vapor barrier. And if you look up here, that's an old classic thing. They've got
2:00
fiberglass between the floor joists right at the rim joist level, and they've
2:07
made some effort to cover this with vapor barrier, but I can guarantee you
2:15
that it's not well sealed enough to cause problems, because there's no way
2:18
you can get the plastic to seal tightly around those joists. It's certainly not
2:23
going to seal very well along the top where it meets the underside of the sub floor either, and any leaking here in a cold climate, any chance that the
2:32
indoor air in the basement can get behind that plastic and eventually work
2:37
its way into that fiberglass, in this case, it's going to condense, and we're
2:43
going to get droplets of condensed water within that fiberglass, and if it's
2:48
cold enough outside, that water is going to freeze. It's going to form frost, and
2:54
the longer the cold spell, the more the frost is going to build up there, and
2:58
when it does eventually get warm, it's going to melt and trigger all kinds of
3:04
mold growth. So don't do this. Another thing that they've really done
3:10
wrong here is that they've got extra insulation here at the bottom
3:14
of the wall, but for some reason it sticks out past the studs, so there's no
3:19
way you can extend any sort of wall board down there, because the edges of
3:25
the wall studs aren't even exposed. And over here, there's some funny business
3:30
going on here. We have a bottom plate here, but nothing to fasten the wall
3:34
board down at the bottom. So, diligence here in the case of the cold air return
3:41
ducts, but, and I'd say, you know, diligence too, when it comes to the walls. I mean
3:46
these walls weren't easy to put up, but the design was flawed right from the
3:52
beginning. It was a bad approach right from the beginning, and you do not want
