Insulating back bedroom

[moonlitcoyote]

So I have had this thought many times and wanted to get some opinions..


The rear wall of my Winnebago is shaped like this ">". It's not that extreme but you get the point. Anyway, my 3 yr old boy sleeps back there and is terrible at keeping himself covered in cool/cold weather so I thought about insulating that rear wall. (the side walls would be easy enough) But I would like to insulate it in a way that I dont have to take the window out and rebuild the entire wall. My original thought was to build an inside wall then put a frame for the window, so it would sort of be like a stick built window with a windowsill. My other thought was if I could somehow make that wall look like this "l" instead of this ">" but I dont think that would work too well. Anyway, if anyone has any ideas or opinions on insulating that wall I'd like to hear them. Thank you

[circleD]

Its sounds crazy but moving blankets are great insulators. I use them over my windows in the rear bedroom of my RV during the summer time and it keeps the heat out just by covering the windows. I get them cheap at Harbor Freight or free on Craigslist. You can fasten them to the walls if need be.

[eXodus]

could you please post a picture ? of the inside and outside ?

I worked the last years in a energy research department and the best insulation these days is according to some smart people:

Rigid insulation out of Polyurethane, but difficult to get
The next would bePolyIsocyanurate
http://www.homedepot.com/p/GAF-0-75-in-x-4-ft-x-8-ft-EnergyGuard-PolyIsocyanurate-Sheathing-1S02/204322724?N=5yc1vZbaxx

which you can get at Homedepot for good price. You would only need to cover the walls with a 0,75 inch thick sheet (just screw or glue it on you existing wall) and this sheet would have much better insulation than you whole walls.

Then just put wallpaper over the insulation. Or paint it directly

[brians1969]

Moonlit you do know that the walls are already insulated with several inches of styrofoam.  Where you are going to have more of a heat loss problem is in the single pane window glass.  It wouldn't  hurt to make storm windows from some thin plexiglass.

[eXodus]

styrofoam was good in the 80s - for sure, but in these days you get double the R-value in modern rigid insulation sheets.

and R-Values add up - so if you got a R5 wall now - and add an R5 sheet you got an R10 wall. Which is about the same which a normal home wall has.

But of course - Brian is right the window is probably the biggest source of heat loss. Double windows help a lot. Or the cheap solution, cover it with big bubble wrap . Or like they in Europe do - a really thick an heavy curtain.

Just short physics lessen:
Cold doesn't get in - heat goes out. It is always from warm to cold.  Never the other way around.

Get a candle search for air leaks. Even a very small leak can cause big heat losses.

[brians1969]

You can also get the shrink film that you use a hair dryer on. Cheap, and you can rip it all down in the spring. Works really well. If you are using the tape on aluminum, make sure the aluminum is warm before applying. Otherwise adhesion is poor. If your windows are anything like mine, they are drafty.

[moonlitcoyote]

I am an insulator by trade so I know all about insulation. My question was really about how to build up the wall over  the insulation without having to get a new window that would span the new thickness, if thats even possible. My back window does need to be re-done as it is plexiglass and not thick enough, but I KNOW that the cold is coming through the walls and so does the heat. When you open the cupboards to get anything out you can instantly feel the cold. And on a hot summer day the rear wall is hot to the touch. With good insulation this would not happen.

So if anyone has any ideas on building the wall over insulation, I would like to hear them, thank you.

[moonlitcoyote]

Just short physics lessen:
Cold doesn't get in -

Really? Well tell that to my feet when the cold is pouring in on them from the firewall or the stairwell... 


Trust me, cold does indeed get in.

[Froggy1936]

ML what you are feeling is cold air getting in Those are the drafts that need plugged up . As physics say heat moves to cold That cannot be changed No matter what your tootsies feel ! I have to rebuild my rear wall also as i sleep right next to it . It is only the normal 1 " thick steyerfoam Thermopanel I am planning on replaceing the small window i installed with a double pane Then adding a layer of insulation board Top to Bottom bent to conform with original shape This is going to require R&R shelf & repositioning lower seating  This will be a couple week job in good weather Not looking forwered to it ! Frank

[pvoth1111]

Hot goes to cold......things give off heat....heat rises
conversely
cold absorbs heat and cold air is heavy and falls

exodus is correct.....though its not just physics...its the laws of thermodynamics.


A draft is carrying away the heat which is why your toes is cold.

somewhere there is a hole where the heat is being transferred....

 

[eXodus]

cold air can get in - sure, but this air taking away the heat of your feet.

That's why I mentioned the candle. Search and chalk every air leak. You can do as much insulation as you want if you got an air leak and loosing the heat and getting air in.

What's the problem with gluing a ¾ or 1" board to your wall ? You can cut the sheets with a knife to size, get some construction adhesive and glue it to the wall, then paint it. It's done in a matter of minutes.

@pvoth I always thought thermodynamics is a part of physics

[brians1969]

It doesn't have to be a draft to lose heat. It could be conduction.

[moonlitcoyote]

I can guarantee there is NO holes in the back bedroom. I can also guarantee that with the door open the cold air COMES IN. But that is all besides the point. This post was not to argue the point of heat leaving/rising/moving to cold or whatever else. I was looking for some inventive ideas on how to build the rear wall that is shaped like ">" but a bit straighter over some insulation. ... The point of insulation is to keep cold things cold and hot things hot. The heat of the sun and the cold of the outside does indeed effect the temperature of the rear wall which in turn effects the temperature of the bedroom. The top half of the wall is covered by a very large window so I cant just put up insulation and then lay a board over it as it would then be at least an inch and 1/8 away from the original wall which would mean the window would also be sunk in. Creative ideas needed not lessons on why my rear wall is hot or cold.

[Rickf1985]

I am watching this thread intently because I am neither an insulation expert not an expert on the design of the interiors of these units. I really want to know all I can about the insulation since I am going to be tearing my slide in truck camper down and rebuilding it very soon and I want to insulate it as good as it possibly can be. I have heard from one camp that says fiberglass is the best and the other camp says insulating board is best. I used the green type high density foam board in a section of my roof that I replaced on my truck camper and I can shoot a laser temp gun at that section and the original with not all that much fiberglass right next to it and they are just about the same. This is middle of the day in the summer sun. Not very encouraging.

[72-d24]

Hi Moonlitcoyote. When constructing this extra layer, I think it will be important to keep in mind that it is not an actual wall that you are attempting to build. By that, I mean that you don't have to actually concern yourself with making it structural. Rather, your goal will be to frame out the false wall in a way that makes it just thick enough for the insulation of choice and provides just enough stability to support the paneling you cover it with. As for the odd angles, frame the bottom and top parts of the wall separately, ensuring that there are no gaps where the two come together. Its just one flat wall on top of another, positioned at odd angles.

Windows always have excessive framing around them to ensure that they are structurally sound. In many ways, you won't need to concern yourself with this because the window is already in place and structurally sound (assumed). However, you may still want to beef up the framing of the false wall on the top and the bottom to provide a solid wall for hanging window treatments and a sturdy ledge for toddler fingers to grasp onto.

Once your wall is in place around the window with the paneling covering it, finish the window by creating a sill around all sides of it. Use thin planks of wood cut to fit perfectly. Yes, the window will be recessed, but there is no getting around that; all you can hope for is that it appears to be somewhat purposefully recessed and nicely framed. There are tutorial online about framing a window sill; you just need to keep in mind that yours is a false wall and does not require all the framing overkill a real window wall does.

I am not a carpenter and I am only offering my opinion as someone who has done some remodeling.

Thermodynamics IS physics, and temperature differences cause air to move (thus, we have wind). The cold air rushes in at the bottom as the hot air rises: a draft. 

[sasktrini]

MoonlitCoyote,

I just pulled the panelling off my rear cap, and found it insulated with fibreglass instead of thermopanel, and partially consumed by rodents or moisture.  I have also realized that some of my thermopanel structure in my walls is delaminated.  Neither construction is up to resist the rigors of winter.

My point… Why not take a closer look and rebuild your rear wall.  rather than just sandwiching another wall in front, get a good look at where the rear cap and floor mate… all the corners… spots where insulation could have deteriorated or gaps developed.

While you have the panelling off and decide what repair to execute, you could consider upgrading your rear window.

There could be any number of reasons why your rear wall isn't up to par.

[eXodus]

Fiberglass is a good insulator and cheap, but as soon it get wets the insulation value gets down to nothing.
and with a rolling house, you always have some setting.
It always depends how soon you want to do the job again ? Get the best rigid insulation you can afford, then you won't have to mess with it again the next 30 years. This stuff is not rotting ever and most insects and rodents don't like it (it's poison you know)

[Oz]

If anyone wants to give advice on how heat and cold transfers through materials, circulates, etc., types of insulation available to use and the benefits and drawbacks to them,  please feel free to do so.  Persons posting questions aren't the only ones who benefit from the information offered, so any additional, relevant information is greatly appreciated and encouraged as others may find it useful.

It all falls under the topic, "Insultating back bedroom".


   

[brians1969]

If fiberglass insulation is getting wet in the walls, there are greater problems than insulating value.

[TripleJ]

Use some rigid foam board to build whatever type of wall you want, cover/trim it out, then shrink-seal the window.

">" and "|" aside, I think the thread would really benefit from having some pictures in it W% W%

[moonlitcoyote]

72D24, Thank you. That was the 1st answer in all of this that pertained to my question and I appreciate it. That is what I was looking for. I had thought it could be done that way but with the odd angle I wasn't sure if it would work or not and did not want to waste money buying lumber that wasn't going to work.

sasktrini, All of my walls are the same, being in the South all summer I learned that all of the walls get hot to the touch inside. The R factor of the insulation isn't enough and there is no dead air space to allow for air movement to cool it. Once insulation gets hot/cold it will retain that heat/cold without any airflow to dissipate it. I am only concerned with the back wall because that is where my child sleeps.

TripleJ, I realize that pictures would be helpful but it is very difficult to show the shape of the wall from a straight on picture and that room is also full with a toddler bed, dresser and toybox that I would have to remove in order to take a picture or I would have added a photo.

Oz, I do believe that Arguing the points of different kinds of insulation and their usefulness would be better discussed in a topic specifically about insulation. How does a person get an answer to a simple question if the original topic is ignored in favor of disputing other facts? An example of that would be if some one was to ask "how do I replace my converter" and then all the replies had to do with why you should replace it or what you should replace it with, how then would the original poster get his answer to "how" to replace it?

[circleD]

I'm not familiar with this model MJ but could you build a thin wall with rigid foam facing the rear and on the interior side make some small thin shelves for storage? Using the 1x2 boards from Lowes. The shelves could hold a few small toys or books with a bungee going across to secure it. Then at the window you'll have it looking recessed a few inches but maybe some shutters or blinds to block out the sunlight  i??  . The total wall would be 1" of foam a few inches of wood and its up to you how deep to make it. This an insulated utility wall and I know how every inch counts.