• If you are citizen of an European Union member nation, you may not use this service unless you are at least 16 years old.

  • Stop wasting time looking for files and revisions. Connect your Gmail, DriveDropbox, and Slack accounts and in less than 2 minutes, Dokkio will automatically organize all your file attachments. Learn more and claim your free account.


Conversation with Christina

Page history last edited by Deanne Bednar 11 years, 2 months ago




On Tue, Sep 15, 2009 at 9:17 AM, Christina A. Snyder



 Deanne, just to remind you, insulating the inside of your stone walls

 with felt, which is moisture permeable, will make the stone walls even

 colder, thus causing condensation to form and stay on the stone walls

 all winter, so that it becomes a perfect habitat for mold and mildew,

 which will likely stain the walls and set up permanent housekeeping in

 the felt, even if it doesn't make anyone sick. Sorry, but you can't

 re-write physics.


 You always want to design so you have your impermeable vapor barrier on

 the WARM side of the insulation, which is the reverse of your plan.

 There are two potential solutions:

 1. Add a impermeable membrane (such as plastic) to the inside of your

 interior insulation and seal it back to the stone top and bottom and at

 all seams (You'll use exposed plastic over your dead body, I know).

 Anything you can do to the inside surface of the felt to make it less

 moisture permeable might help, such as building up a thick coat of clay

 slurry over its surface in several coats, and then possibly a layer of

 oil over that. Unfortunately, since you'll be removing the felt

 seasonably, a clay surface would crack and leak when moved, so you'd

 need to renew the surface every time it was removed. And if you did put

 an oil layer on, that would make the next coating of clay not want to

 adhere, so maybe the oil is a bad idea. Possibly whitewash might work,

 but it is very brittle, so it it was even bumped after it dried it


 crack and let moisture in to feed mildew. However, lime washes are

 supposed to reseal if cracks if recoated. No good organic answers to

 flexible, impermeable barriers, unless you can grow one like an orange



 2. Put your insulation on the outside of the impermeable stone, so that

 it makes the stone get warmer, not colder. This will mean that you will

 need to matt the outside of the felt into as smooth a surface as you

 can, and treat it liberally with oils so that any rain will sheet off.

 Since it touches the ground, you may also have moisture or insects get

 into it from the ground, and I don't have any solutions for that.


 Best wishes,



On Mon, 21 Sep 2009 22:19:35 -0400, "Deanne Bednar" <ecoartdb@gmail.com>



 that is a lot of challenging news!  thanks for your consideration and


 My vision on this is the castle made of rock with the large tapestries


 I assumed beautified and kept the place warmer.  I included some quotes

 below which might give some traditional-style data.


 I get what you mean regarding warm air hitting the cold and condensing.


 haven't noticed that except during moist hot summer days that get cool

 nights and the warm air condenses on the rock on the interior.  I get

 freaked out, but have learned it will just go away in a day or so.


 I would be agreeable to plastic on the interior of the felt, or even

 recycled bubblewrap if they were needed.  good idea.


 Maybe the SBS doesn't have much moisture since there isn't water, shower,

 plants or even people usually in there.


 I will bring this to the attention of the participants, and will still go

 ahead with the workshop, because i an interested in how to make pillows,

 cushions, etc from raw wool.


 I would love to see how your project is going.  It is hard to keep up


 anything over here, and I am going through a period of discouragement,


 that too shall pass.

 3 interns now.  but winter is coming.  what stage are you at?

 love, deanne


 History of tapestries In the middle Ages, tapestries had a purely

 utilitarian function. They were originally designed to protect medieval

 rooms from damp and cold weather, to cover austere walls of big castles,


 to insulate big rooms into more comfortable quarters. Tapestries used for

 furnishing big stone castles were very big in size and they required big

 looms, many workers and high capital investments. Thus, manufactories of

 this type arose in prosperous localities, usually weaving centers. By


 Flanders, especially Brussels and Bruges, had become the chief places of

 production. Due to their size and intricacy, tapestries became


 and displays of wealth and power.


 "Stone Castles replaced the earlier form of motte and bailey type





 The most important building in the castle was the .

 It was often  cold and draughty. The was a long room

 that had the lord and ladys table at the top and *tapestries* with scenes of battles


 hung on the walls.


On Wed, Sep 23, 2009 at 1:29 AM, Christina A. Snyder



 You are right that keeping the amount of humidity generators (people,

 plants, cooking, showering) in the SBS down in winter will help, but it

 won't eliminate the condensation phenomena if you are heating the room

 air so it has higher moisture capacity and you allow the warm moist air

 to get behind your interior insulation next to the colder rock wall.

 Even the woodstove burning wood releases moisture, though most goes up

 the chimney.


 The condensation phenomena is identical to that at UHEAC, where the

 homemade insulating curtains in the presentation room cause lots of

 condensation on the window glass because they make the window colder yet

 don't seal the room air away from the window. The room air is constantly

 flowing down past the window being dehumidified as it cools. Yet the

 same building has an example of good interior insulation in the kitchen/

 sitting area, where the insulation has a vapor impermable layer on the

 inside and seals to the edges of the cold window in a track, thus no

 significant condensation develops. The more you can replicate those

 features of in your design, the happier you'll be.


 I've not lived in many castles, though I've visited lots, and many did

 have condensation problems. I'll bet that where they put a tapestry in

 the middle of an exterior wall they had condensation and even

 mold/mildew problems. If they managed to make the tapestry cover the

 whole wall and fit tightly to the edges, they probably had less

 problems. Like the SBS, they had little sources of humidity in most

 castle rooms, since they didn't have showers or plants, cooking wasn't

 done in the living spaces, so people were the only sources. Since they

 didn't have glass windows in medieval times when those tapestries were

 made, the interior humidity couldn't really get much above they dry

 winter air outside. I'll bet a lot of historic tapestries were lost to

 mold/mildew when people began adding windows. Maybe they eventually

 learned to hang decorative tapestries farther from the cold surfaces,

 even though that would have reduced protection against heat loss. They

 also made and lived in small tapestry tents within the larger cold stone

 rooms, such as inglenooks and canopy beds - since these draperies

 weren't against the cold surfaces they wouldn't have had nearly the same

 mildew issues.


 You are right, summer condensation isn't much of a problem since we

 don't have absorbant materials against the cold wall surfaces then, and

 because it does go away as soon as the humidity in the air drops. But in

 winter in a poorly insulated building (or portion thereof), even

 furnishings like beds and couches pushed against cold walls can cause

 mildew to form on both the walls and the furnishings, as we've

 discovered to our sorrow in this old farmhouse. The moisture on the cold

 surface builds up over weeks and doesn't go away for months, so the

 mildew has everything it needs: moisture, organic material to eat,

 oxygen, and temps above freezing = population explosion! I didn't want

 to rain on your parade, but thought if you were forewarned you might be

 able to design your insulation so as to deprive these micro-organisms of

 at least one of the things they need to thrive, like the moisture. Its a

 lot easier to prevent the growth than to kill it off once established.


 I doubt you'd find the garage we are just finishing very exciting, but

 we'll get to the house this next year. Hope this finds you well!






Dear Christina,

 Thanks again for your thoughtful input !

 Another thought I had about the castles is that they probably had almost

 NO heat in them...to cause condensation.  Just guessing of course.

 I do remember the conversations from the past about keeping the thermal

 loops from bringing hot, moist air up under the felt/insulation

 layer....and the need to make it fit tight....that is something I have kept in mind.  It probably would have been wise to cut up an old army blanket and experiment for the previous winter to see how it preformed before going ahead...but I want to make length of this wool felt anyway, and can use it for cushions on things.  Kylie wants to

 present at the Natural Building Colloquium East next year on this, so it is also

 furthering her goals.  A couple from MSU are building a yurt and are

 geeked...plus some others...so those things are valuable in themselves.


 Glad to hear the update on your garage, and will definetly check your


 building out next year ! ! !


On Thu, Sep 24, 2009 at 10:15 AM, Christina A. Snyder  wrote:

Experimenting with a couple of different insulation designs is a great

idea to see what works best, w/out wasting much materials. Center of

insulation results will likely be different from edge effects, so don't

make the test pieces too small.

Castles did have fireplaces in at least the rooms of the wealthy, and of

course the kitchen. But without tight windows (oiled parchment was used

before glass), the fire would actually make the rest of the room colder

by pulling in more outside air, so you'd only experience warmth if

sitting almost in the fire. When thermal mass stoves appeared, it was

better, cause a short intense burn could heat up the stove mass, then

when the fire was out it wouldn't pull in more cold air, but the heat

kept radiating from the mass. Some stoves were built with the bed

platform on top.

Best wishes,



Beautiful response, Christina,

What a rich and fair mind and heart you have.

Love you,


Comments (0)

You don't have permission to comment on this page.