Hi

I'm renovating the basement of an old house in Victoria, BC. The
climate here is typical Northwest. It rains a lot, but rarely does it
get below freezing.

The building code in this area says I should put vapor barrier on the
external walls between the drywall and the insulation. This is to
prevent in-house moisture from penetrating through the drwall and
insulation and condensing against the cold external walls. It's the
same building code across Canada.

My carpenter says however, that this code is relevant in climates like
Alberta where it gets to -10 and stays there for months on end, but
that for climates like BC where it hardly ever gets below freezing it
does more harm than good. His recommendation is that I not use vapor
barrier on the external walls and simply drywall right over the
insualtion. According to him, in temperate humid climates like British
Columbia, vapor barrier seals the moisture in the walls and causes more
wood rot and mold than without it.

(He does, however, recommend putting vapor barrier up against the
foundation (~ 2 feet) BEFORE the insulation and then drywalling. That,
he says, is to prevent the outside ground water moisture from coming in
through porous concrete and into the walls.)

What is your guys' opinion? Is he correct? Would you vapor barrier the
external walls between the insulation and drwall in humid climates that
rarely get below freezing?

Thanks for your thoughts.

Jack

The building code in this area says I should put vapor barrier on the
external walls between the drywall and the insulation. This is to
prevent in-house moisture from penetrating through the drwall and
insulation and condensing against the cold external walls. It's the
same building code across Canada.

Vapour barrier should be placed on the warm side of the wall. Anyplace in
Canada that would be the side towards the living space. It's to prevent the
humid air in the living space from getting through the wall and condensing
in your insulation and framing.

If you want to put any kind of barrier on the cold side of the wall, use
something like Tyvec... It allows air movement through it but is designed to
reduce moisture movement through it.

wrote:
Hi

I'm renovating the basement of an old house in Victoria, BC. The
climate here is typical Northwest. It rains a lot, but rarely does it
get below freezing.

The building code in this area says I should put vapor barrier on the
external walls between the drywall and the insulation. This is to
prevent in-house moisture from penetrating through the drwall and
insulation and condensing against the cold external walls. It's the
same building code across Canada.

My carpenter says however, that this code is relevant in climates like
Alberta where it gets to -10 and stays there for months on end, but
that for climates like BC where it hardly ever gets below freezing it
does more harm than good. His recommendation is that I not use vapor
barrier on the external walls and simply drywall right over the
insualtion. According to him, in temperate humid climates like British
Columbia, vapor barrier seals the moisture in the walls and causes
more wood rot and mold than without it.

(He does, however, recommend putting vapor barrier up against the
foundation (~ 2 feet) BEFORE the insulation and then drywalling. That,
he says, is to prevent the outside ground water moisture from coming
in through porous concrete and into the walls.)

What is your guys' opinion? Is he correct? Would you vapor barrier the
external walls between the insulation and drwall in humid climates
that rarely get below freezing?

Thanks for your thoughts.

Jack

Go with the code.

--
Joseph Meehan

Dia duit

i am personally skeptical about the advisability of fiberglass
insulation in a basement. fiberglass and moisture is not a good
combination. in a basement, you not only have to worry about moisture
from the house, you also have to worry about moisture from the concrete
walls.

IMHO rigid insulation is the way to go in a basement. there are a
number of options for attaching drywall. USG makes a z strip that
fastens to the wall and provides a surface to screw drywall to.


BTW you could go with a vapor impermeable primer on your drywall,
instead of plastic.

I live in Ontario and ahve to say that vapour barrier is really easy to put
up. Make sure that they also put some around all of the light and electrical
boxes to stop air movement. IT's hardly worth debating. BUT like another
post I'd use rigid foam if the basement has ever had water in it or urathane
spray foam.


wrote in message
oups.com...
Hi

I'm renovating the basement of an old house in Victoria, BC. The
climate here is typical Northwest. It rains a lot, but rarely does it
get below freezing.

The building code in this area says I should put vapor barrier on the
external walls between the drywall and the insulation. This is to
prevent in-house moisture from penetrating through the drwall and
insulation and condensing against the cold external walls. It's the
same building code across Canada.

My carpenter says however, that this code is relevant in climates like
Alberta where it gets to -10 and stays there for months on end, but
that for climates like BC where it hardly ever gets below freezing it
does more harm than good. His recommendation is that I not use vapor
barrier on the external walls and simply drywall right over the
insualtion. According to him, in temperate humid climates like British
Columbia, vapor barrier seals the moisture in the walls and causes more
wood rot and mold than without it.

(He does, however, recommend putting vapor barrier up against the
foundation (~ 2 feet) BEFORE the insulation and then drywalling. That,
he says, is to prevent the outside ground water moisture from coming in
through porous concrete and into the walls.)

What is your guys' opinion? Is he correct? Would you vapor barrier the
external walls between the insulation and drwall in humid climates that
rarely get below freezing?

Thanks for your thoughts.

Jack

On 19 May 2006 00:52:08 -0700, wrote:

Hi

I'm renovating the basement of an old house in Victoria, BC. The
climate here is typical Northwest. It rains a lot, but rarely does it
get below freezing.

The building code in this area says I should put vapor barrier on the
external walls between the drywall and the insulation. This is to
prevent in-house moisture from penetrating through the drwall and
insulation and condensing against the cold external walls. It's the
same building code across Canada.

My carpenter says however, that this code is relevant in climates like
Alberta where it gets to -10 and stays there for months on end, but
that for climates like BC where it hardly ever gets below freezing it
does more harm than good. His recommendation is that I not use vapor
barrier on the external walls and simply drywall right over the
insualtion. According to him, in temperate humid climates like British
Columbia, vapor barrier seals the moisture in the walls and causes more
wood rot and mold than without it.

(He does, however, recommend putting vapor barrier up against the
foundation (~ 2 feet) BEFORE the insulation and then drywalling. That,
he says, is to prevent the outside ground water moisture from coming in
through porous concrete and into the walls.)

What is your guys' opinion? Is he correct? Would you vapor barrier the
external walls between the insulation and drwall in humid climates that
rarely get below freezing?

I'd use a spray-on close-celled foam as both insulation and vapor
barrier. You get no condensation against the sheathing because
there's no way for air to carry water there, and you get no
condensation against the vapor barrier, because the "exposed"
surface isn't cold.

Is he correct?

No. Go with the vapor barrier and ditto on the rigid insulation. You don't
want mold.
--
Mac Cool

Thanks for everyone's response. It seems like the consensus is that I
should use vapor barrier. However, I haven't received any good
arguments for other than the reason I mentioned.

My carpenter specializes in renovating old homes. He says that he's
never taken apart a house that did not have vapor barrier and had
problems with mold, but he's taken apart many homes WITH vapor barrier
and seen lots of mold and wood rot.

I'm not sure who to believe.

Jack

your carpenter has a point about never seeing mold in houses without a
vapor barrier. i hink old houses are so leaky that they are vented
naturally. but if this is a basement with concrete walls, it might be
a different story. my house is 90 years old--probably without a vapor
barrier, but someone tried to finish part of the basement some years
ago and now it's a rotted mess. it was water from the outside, i'm
pretty sure. so i'd ask him how many old basements insulated with
fiberglass he has dealt with.

So I asked a vapour barrier expert. His main job is to repair water
damaged homes. And he confirmed what my carpenter said. Best not to use
vapour barrier if you're building outside of code.

His rationale was that IF there ever is water damage, the vapour
barrier will hide it and prevent it from being noticeable on the
drywall. In the meantime the moisture will do a lot of damage to the
walls and end up costing a lot more to repair than had you noticed the
water damage on the drywall and gotten to it right away.

You learn something new. I've decided NOT to vapour my house in the
temperate climate of Victoria, BC. In colder climates, definitely use
vapour barrier.

Cheers,
Jack

:

It seems like the consensus is that I
should use vapor barrier. However, I haven't received any good
arguments for other than the reason I mentioned.

The insulation will minimize the heat differential between the concrete
walls and the conditioned air space inside helping to prevent condensation
on the walls. The vapor barrier will keep the moisture inside further
preventing condensation on the concrete wall. Ever walk outside in the
morning and see dew or frost on your car windshield? The windshield is a
vapor barrier keeping the condensation outside, rather than inside.

If you are having moisture problems from outside then do not use
fiberglass insulation, use rigid foam.
--
Mac Cool

Jack,

Do as you will - Vapour barrier or no Vapour barrieer. However, I'd
recommend talking to a local building association for advice prior to
making you final decision.

I happen to live just a couple hours north of you. Nanaimo.

Before making your final decision on this matter check out the
Vancouver Island Home Builders Association and maybe call the local
building inspectors. You can call anonymously if you like and ask your
questions (contrary to popular belief, the inspectors are there to
protect the homeowner!). The Home Builders Association can probably
supply you with some free information as to the whys and wherefores of
vapour barrier and the inspectors would prefer to have the questions
asked before it creates an issue - so that you don't have the costs of
repairing it after if it is done incorrectly.

Just my 2 cents....

Best of Luck on you project!