Home>Discussions>INSULATION & HVAC>Queen Anne: Insulation and Vapor Barrier
2 posts / 0 new
Last post
Queen Anne: Insulation and Vapor Barrier

Hi, I have a 1901 Queen Ann in climate zone 5 in Northern Indiana and in every other frame cavity is filled with brown/grey loose fill/blown-in insulation that I can only assume has been there for awhile per the attic. They laid it over the floor in the attic and some open floor joists areas, and noticed that it has broken down into a black dust underneath. But it is still well packed in the cavities where filled, it has not collapsed, so thats good.

But I've been reading and finding different information on the ability of the house to breathe vs moisture barrier vs thickness of the exterior insulation/siding vs new insulation etc.

Well, my house has accumulated a lot within it's 118 years, from four to five layers of roof shingles (replaced) to five layers of siding material (Per images) that measures 3.5" thick, then you have in the interior,  lathe strips and 1" of plaster wall. 

So with what I read from another site, that with the exterior of thickness from the multiple siding materials, that I don't have to worry about moisture if I was to add more blown in or batting insulation. 

Is that correct?  Could I add more blown in insulation to the empty cavities or should I remove all plaster and lathe, attach vapor barrier by weaving it within the frame and cavities before adding insulation batting and dry wall (not sure if Id be good enough to replaster)

Thanks in advance!

(Added links to the images from google drive)



Re: Queen Anne: Insulation and Vapor Barrier


Never remove the plaster covered walls and ceilings unless this is a last ditch effort to try and keep it from faling off. Why do you feel that you need to have insulations in the wall cavities? There is very, very little air movement between the outside and the wall on the inside. Most likely that air movement is coming in from some where else. Not thru two walls. You will find that if you remove the trim from around a window, that you will have air movement. This is where you need to concentrate any insulations efforts. You will have an issue with moisture between all those different layers because no air and get between them to dry out the water. This is where there is a hole that is allowing water to come in, become trapped down in the layers and not being able to dry.

When you walk outside in the winter, you layer your clothing to keep your body temp from dropping faster than it can generate heat. But once you are inside an area where the air temp is stable enough to keep your body from working so hard, you remove the layers. Same as if your clothing gets wet, you take it off as quickly as you can, even in the heat of summer, because your skin will not dry and make your body cold. Same as if you should remove your over coat before getting into a car for a lengthy journey. You do that so that your body temp can level off. Your body needs outside air to keep it dry because it is producing moisture.

Our house has the same type of material in the attic that you described. You cannot change the way the structure is designed. And you cannot follow modern day practices and principles on your house structure. The structure was not designed for things like that. It is designed to breathe. And it does that well. Plaster is a much better insulator than sheetrock ever can be. Plus sheetrock has paper covering it. That and a little bit of moisture will cause rot and mold to form. You do not want to put some modern house wrap on an old structure. I am not by any means telling you to replace all the windows either. A good solid wood window has better properties of stopping air movement than any of the new plastic windows. Don't get all caught up on the double and tripple pains of glass with argon inbetween. It all comes down to what holds that glass to the frame of the window. Could be that you may want to rebuild all your windows. I have gone thru our house and done that to each window. You will get much more added resistance to air movement if you concentrate on the holes in the house that allow air movement, then you would trying filling the stud bays with enough insulation to compensate. It cannot be done because you have at the maximum 4 inches in width.

Did you know that when you use a house wrap, there cannot be any holes or open seams in the wrap? If you look at the so called house wrap from most companies, especially the low quality brand the box stores carry, you will find that it is covered with small holes. Your issue is that you have way too many layers of building material over the outside covering. All of that needs to be removed, down to the original clap board. Seal the joints between the clap boards that is a small gap or hole that is allowing air movement. Adding insulation into the stud bay will only allow the moisture a place to land and start rot and mold. Right now the inside of the wall, attic and floor joists are nice and dry. The wood has no moisture, just the way you want it. Fix the issues, don't compound the issue by adding something a structure does not need.

We have an old Victorian just like you. I have found in a few places the clap boards were a little lose. I removed the nail and put in a stainless steel ring shank nail in a new hole. Sealed up the old nail hole and that pulled the clap boards together, sealing up the gap where air was coming in. For some, use a high quality caulk to help seal that line.

My advice and experience comes from living in a Victorian house all of my life. One in Ky and my own in NC. Stop the airy from coming in thru the smallest of gaps and holes. Most of the houses have an equilivent of a full sized window opening in the combined gaps and cracks in the outside walls, around doors and windows. I use a smoke pen to determine where the air movement is located. Then I concentrate on the outside of the structure first.


Handy Andy In Mt Airy NC

Sponsored Stories

TV Listings

Find TV listings for This Old House and Ask This Old House in your area.