MasonJar Wrote:By the way, I understand that several good coats of latex paint also count as a vapour barrier in situations where it would be impractical to retrofit one (e.g. old homes with plaster walls and no insulation).

Andrew

My house is like this. It's brick and block construction. No 2x4 studs in the exterior walls. The walls are strapped and then covered in lath and plaster.

It is really "cool" to have this forum so we can discuss this stuff. I never really thought about the differences in housing construction based on climate and location. We all see how things are done where we live, and then we assume that houses should be built like that everywhere. I know I am like that. When the vapor barrier was first mentioned several pages ago, I was thinking "What? Vapor barrier? Under the sheetrock? Never saw it before!" And you cold climate guys are looking at my building thinking "Uh oh, he needs vapor barrier!"

I am sure that a house built at the north pole would need to be done differently than in the Sahara dessert. And most likely there is a gradient in between the extremes. Apparently Houston is about in the middle. We probably have a few days in the winter where a vapor barrier under the sheetrock would be helpful, but then we have plenty of days where the vapor barrier would serve no function at all, and perhaps even be a problem by trapping moisture that is trying to move "the wrong way." As for condensation in the winter months, there is a huge difference between 10 degrees F outside and 70 degrees F inside versus 40 degrees F outside and 70 degrees F inside.

Thanks to everyone for their comments.

Will post more progress photos this evening.

Tetters: So your house is face brick on the outside, and cmu block on the inside, then plaster? What is the total thickness of the walls? Must be a foot? Is there any insulation in the block, or foam type insualtion sheet anywhere?

Marty: In our existing attached 2 car garage, we will have a few days in the winter where the concrete floor gets wet from condensation. I think this is mostly when the weather has been cold, and then suddenly turns hot and humid. The cold slab will make the water vapor condense. But the garage really isn't sealed against the elements due to the garage doors. On the other hand, in the house, we lived on concrete floors for about 7 years (We had Tilson Homes build our "shell" and then we took our time finishing everything, thereby saving tons of money) and we never had any condensation on the concrete. So I'm pretty sure everything will be okay.

Andrew: Seems we have a mixture of milder climate down here, sometimes cold out, hot in, or hot out, cold in, and the compromise is not to use a vapor barrier. I'd like to witness the construction of a home up in Canada (brrrr cold!) just so I could see the pains taken on keeping everything insulated and sealed and vapor proof. I'm sure it is all much more complicated and tedious (and expensive) than what we do.

Gary S Wrote:Tetters: So your house is face brick on the outside, and cmu block on the inside, then plaster? What is the total thickness of the walls? Must be a foot? Is there any insulation in the block, or foam type insualtion sheet anywhere?

Yep Gary. That's about it. Face brick then cmu brick on the inside, 1 x 2 straping then the lath & plaster. I would say that a foot is an accurate estimate for the walls. No insulation. The house was constructed over fifty years ago when code was different and it was determined to be an acceptable form of construction for homes. There is wood structure for the interior walls, floor and roof. I have heard that there are companies that can come in and inject spray foam insulation into the walls to fill the gap between the lath and plaster. I have not really looked into it. The other option (as I understand it) would be to gut the interior to expose the brick, seal the brick on the inside, and then construct 2 x 4 walls inside the home, insulate, vapor barrier and sheet rock it. In other words messy and expensive. I've also heard that you need to leave a consistent gap so that the brick does not touch the wood, something like a 1/4 - 1/2 inch. As the brick can still have moisture and the wood can get moldy and rot.

Like I mentioned, I only did a cursory look to see my options... so I might have my facts mixed up about what I'd need to do to the house to bring it up to code. I've had a number of people tell me I should check the insulation in my ceiling and throw another layer on top. This will apparently, significantly reduce heat loss and then home will warm up quite noticeably. I just have to drag my ass up a ladder to peak up through the access panel which is in a very full closet at this time.

I can't remember ever seeing a house down here that was built that way. On the other hand, I have seen plenty of commercial structures that were built like that. And now that I think of it, alot of those buildings didn't even have plaster on the inside. They just sealed and painted the cmu.

As long as your utility bills aren't outrageous, I'd say don't mess with insulating the walls. In one of my home remodeling books, they give a list of insulation projects ordered from most cost effective to least cost effective. Insulating existing walls is the very last item on the list, because it is generally quite expensive to get inside them. Now, I agree that you should take a look in your attic. If there isn't sufficient insulation, it would be fairly easy to add more.

I put in three hard days of work and made good progress. The weather was fantastic, I was in shorts and T-shirt all 3 days. Today, I would almost say it was warm!

First, I completed the sheetrock on the ceiling:

[attachment=19619]

Then I made a big dent in finishing the soffits and brick trim. These 2 photos show the gable end soffits and brick trim going up to the roof peak:

[attachment=19618]

[attachment=19617]

And here is the soffit under the eaves. I used the hardiplank which has the vent holes already in it. You can see them in the photo if you look closely.

[attachment=19616]

And finally, a picture of the this evening's sunset taken from the roof of the building.

[attachment=19615]

Here's one method used in western Canada and it will certainly be used in southern Ontario if we build another house. I do see a couple of weaknesses in the method, but they're easily correctable.

Wayne

Dang, Wayne, you guys up in the great white north do some weird things when building!

Gary S Wrote:Dang, Wayne, you guys up in the great white north do some weird things!

As far as I'm concerned, Gary, there was no need to qualify your statement with "when building".

Wayne

Gary S Wrote:I ... I was in shorts and T-shirt all 3 days...

Ok, it works. I feel lousy now... Greetings from snowy Germany

ps. My wife and me have been several times in the Houston area over Xmas and had great new year parties at the Hilton in Corpus Christi. A ballroom full of Texans and two Germans is a great experience. It was great to walk at the beach at north padre island on the morning of the 1/1

Hey Gary. Yes buildings seem very different from one place to another .A few years ago I did a coarse on what they called here a R 2000 home .I dont think it was built as good as it could have been .To airtight and they always smelled musty .In those you a continuus vapour barrier from the foundation to the roof.The walls were built useing 2x6 and r 20 insulation.The attic went from an r12 to now a r32 which is also minimum code now .It had some good ideas but were a pain for builders.Once the building was finished the HVAC system also had to include an air to air exchanger because they were so air tight.I enjoy watching what others do .I feel sometimes if I comment on a post im sticking my nose where it dont belong.Therefore I keep to myself alot.I will look for some pics of my old layout as it is gone now .It seems that life,an unhappy marrige and slow to no work all caught up with eachother at the same time .Wow ,what a bang that was.Thanks for the welcome to the board and Im glad I chose this post to jump in on and get my feet wet .My love of trains came from my father who himself was an engineer.He worked for Westinghouse in Hamilton here running an old porter fireless cooker .He loved that old girl aways keeping her going one way or another .I only saw it a couple of times as I was very young at the time 4 or 5 maybe.After it was retired it sat on a siding of the TH&B railway up until it was towed down for scrap .From there he was transfered to another plant in town and on to the 50 tonner they had .I think I was about 3 when he bought me my first train set .An old mark tinplate set that ran in a small oval after you wound it with a key.I still have it here .the only thing missing is the key .It is in good shape for a set almost 45 years old.I now live in an apartment and have built a small switching layout .My other layout was in a room of 12x16 with only a 3 foot path to the back door.On the days I ran it I had a drop in for the back door .My dogs didnt like it cause they were stuck outside for awhile.As I say I will find some photos and post them . Just alittle about me .Thanks again .MartyG.

Hey Marty, looks like you have alot of history behind you. Even though your previous layout is gone, I'm sure you have a lot of knowledge and experience that you can share through the forum. I'm looking forward to your continued participation. I mean, even your very first post was fruitful in that it got me to thinking and doing some research about how things should be done, and I like that. Thanks Marty G!

I certainly know more about vapor barriers than I did 2 days ago, and knowledge is the most valuable thing in life. As an example, here is a map I found at <!-- m --><a class="postlink" href="http://www.energysavers.gov">http://www.energysavers.gov</a><!-- m -->. I am surprised that the "no vapor barrier" zone is so small.



Again, welcome to the forum and I hope to see some photos and more posts from you.

Thanks,
Gary

faraway Wrote:Greetings from snowy Germany

I've lived in Houston my entire life (almost 50 years) and can recall having snow on the ground maybe 6 times. We may get a snowfall about every other year, but the ground is generally too warm for it to build up. It generally just melts as soon as it ends its downward journey. A few years ago, on christmas day, we woke up to 6" of snow on the ground, the most ever. It was a very nice treat and something to remember. But I'm sure that month after month of snow would get old in a hurry!

faraway Wrote:ps. My wife and me have been several times in the Houston area over Xmas and had great new year parties at the Hilton in Corpus Christi. A ballroom full of Texans and two Germans is a great experience. It was great to walk at the beach at north padre island on the morning of the 1/1

Winter is the best time to collect shells on the beach. Even though Texas doesn't have the most beautiful beaches, it is a nice trip every once in a while. North Padre has coarse brown sand which tends to muddy up the surf, but further south at South Padre, the sand is finer and whitish, making for a more attractive beach.

So what is your connection to Texas?

I am curious what builders would say about moisture barriers here in southern Arizona. The Dew Point is the temperature at which water vapor from the atmosphere will condense. In other words, if the dew point equals the air temperature, the relative humidity will be 100%. If a surface is warmer than the dew point, no condensation will occur. In the Phoenix area, the highest the dew point will ever get is about 70 degrees Fahrenheit, and when that happens it is usually for just a few hours following a summer rain storm. Because i never cool my house below 70, I should not have any condensation issues in the summer. In the winter, the dew point inside my house is pretty low, probably around 30-40 degrees at maximum. Inside moisture is probably at a maximum when I am boiling pasta :mrgreen: . That means my attic and wall temperature would have to get down to 30-40 degrees for moisture to condense. That may happen about 5-10 nights per year, but only for a few hours. In my location, I can't see where a vapor barrier on either the inside or outside will be needed.

In Houston, I would imagine the summer dew points can exceed 80 degrees, with the outside air temperature in the 90s. Assuming you air-condition your house to less than the dew point, I would think you want a vapor barrier on the outside.

Gary S Wrote:...So what is your connection to Texas?

You got a PM