1948 Southern California coastal house renovation thread

[Daox]

S-F made a great video on how to properly dense pack a wall cavity. I can't see it being properly packed full without a tube being shoved into the wall...

http://ecorenovator.org/forum/conser...html#post22803

[S-F]

Get more quotes. If he doesn't know about necessary pressure he shouldn't be trusted. What kind of siding do you have? Unless it's something like asbestos or brick you can remove it in small sections.

[rhizomatic]

Thanks! It is wood siding. There are videos online that show people installing blown-in insulation by removing siding and then cutting a hole, so I was surprised that he wouldn't do that but would instead opt for patching my interior walls. In part of my living room I have wood paneling... he can't patch that satisfactorily.

[S-F]

It's very difficult to patch holes in drywall properly. When we do it it always looks pretty bad so it's a last ditch situation. All wood siding is easy to remove. Shingles, clabs and so on cut right of and go back on so you'd never know.

[rhizomatic]

Having cancelled the previous blown-in insulation contractor, I am close to hiring another after further searching. But my wife is now paying more attention and has been raising concerns about moisture. This 1948 cottage is without a moisture barrier inside the walls, and she has read from Bob Yapp that we should avoid insulating the walls: Myths About Insulating Old House Walls. The upshot? He insists only attic, roof, and basement insulation should be used in old houses, or face the moisture consequences. He is talking about plaster, and I have mostly, maybe almost entirely drywall. Does that matter?

Answering a comment below the article, Yapp suggests a retrofit that might solve the problem of moisture infiltrating the insulation:

You can paint the interior plaster on the exterior walls with an elastomeric paint product (paint that doesn't breath) to stop the interior water vapor from entering the wall and soaking your cellulose insulation. You'll need to caulk the trim to the plaster and add gaskets to the wall switches and outlets to get the most continuous vapor barrier possible.

And he recommends this supplier for such paint products: roof coatings, roofing fabrics and wall restoration system.

I need to get a better understanding of this issue before I'll easily convince my wife that we're on a good path. I'll keep reading online, but if there are good opinions here, I would love to hear them.

-james

[rhizomatic]

Been air-sealing this old house better, and what a world of difference. The underfloor insulation is not complete yet, but with doors sealed, crawlspace sealed, and DIY storm windows beginning to go up on some of the antique windows I have, I am starting to feel a really significant difference.

I'm making the storm windows with acrylic for glass, wood molding framing (i'm making mitered corners), and weather stripping to create a friction seal to hold the window in place. The worst-leaking windows are getting the treatment first.

[Daox]

Sounds great. Can we see com pictures?

[Exeric]

Hi Rhizomatic,
If I'd read this thread previously I wouldn't have asked some of the questions i did in another thread about this subject. I also live in California, 100 miles north of the Bay Area. Let me assure you that you don't need to worry about not having a moisture barrier where you live. It won't cause problems for your house if you don't have one. In fact it will cause you more problems if you DO have one.

Moisture problems from not having a moisture barrier occur in areas that get extremely cold in winter. Because the interiors of houses are conditioned spaces they are warm and can hold a lot of moisture, even in cold weather outside. When it is very cold outside the moisture that air can hold is very low. Consequently a huge vapor pressure differential builds up in cold weather that drives that moisture through the wall from the inside to the outside.

Even in warmer climates that happens to some extent but orders of magnitude less. And
what little does occur in warmer climates easily drys out when outside temperatures warm up. That is really how you judge whether you need a moisture barrier on the inside. That is, you determine it with both the moisture differential that builds up between inside and outside habitats AND by the construction details in the house that allows for drying when things warm up. In all parts of California, except for high elevations, you don't need a moisture barrier in the walls. An air barrier is another story. That's always good. Hope that helps you and your wife's state of mind.

[Exeric]

Here is a good resource for all things vapory in buildings. If you read all that you will know more than 99% of people, even yappy Bob Yapp:

http://www.buildingscience.com/resou...r_code_changes

[rhizomatic]

Originally Posted by Daox

Sounds great. Can we see com pictures?

I'm planning to make another today, and this time I'll take some snaps. Promise!

Originally Posted by Exeric

Here is a good resource for all things vapory in buildings. If you read all that you will know more than 99% of people, even yappy Bob Yapp: Vapor Barrier Guidance — Building Science Information

This is great. Thanks. I went into Lowe's for clothes line supplies (old one snapped and I thought I'd redesign it) and when I dropped-in on the pain department to ask about "elastomeric" paint, I was shown some exterior paint and when I suggested in might be used internally on plaster walls, I was told to just use a good latex... that the elastomerics will off-gas longer because they are meant for outside and they won't do much more inside than a good interior latex.