Radiant Heat Loss - Sunroom & Wood Stove Woes.

[MagdalenaP]

First, see old pic (no current pic), the stove now is under where the clock on the wall is, door facing the window. I'm getting ok burn times, around 5-6ish hours. Stove is rated for 8 hours. Anyways, I posted in the hearth section and am being told I'm loosing radiant heat, through the triple glass windows...and that curtains *may* help.

I guess I'm just struggling to understand how heat can go out tripe pane (non opening/no leaks) windows so well, but not fabric curtains. Would curtains really help?

What about a radiant barrier some like this: (broken link removed to https://www.radiantguard.com/collections/radiant-barrier/products/radiant-barrier-xtreme-metalized-insulation-xtr500b) I understand it wouldn't look great, but it would just be for winter and mostly at night.

Thoughts? Has anyone noticed a huge difference with better curtains? Thank you in advance.

 

[SpaceBus]

We use insulated drapes, you saw the post where a member made quilts for her windows. They absolutely make a difference on heat loss. Stand next to your windows and you will feel the heat loss, then stand next to a regular insulated surface. We are thinking about putting in some floor to ceiling windows on our second floor and will definitely be using insulated drapes or making window quilts.

 

[SpaceBus]

That product you posted would be great for trying to reflect some heat back at your house. Mylar might also help. This will not be an easily won battle.

 

[zrock]

Not sure why u did not just continue the original post.. but owell lol... stand by any window I don't care if its top of the line or bottom of the line. You will always feel cold and a slight draft it will just be defendant on quality of the window. The curtain creates the thermal brake. Just like keeping the hot sun in the summer it will keep the heat on the hot side and cold on the cold side

Sent from my SM-G950W using Tapatalk

 

[peakbagger]

Yes the radiant barrier is short term fix with some major caveats. Make sure the product is non flammable, if it inadvertently gets set on fire it will burn quick and most likely take the house with it. Unless you can get it tightly sealed against the window frames you will get a lot of convective flow between the curtain and the windows which can suck some heat out of the house. You also may have moisture buildup on the window frames, this can lead to water and possibly black mold collecting in the edges and the sash.

There are two longer term fixes. If you have sewing ability window quilts work pretty well but can have the same issues as the radiant barrier and when retracted they take up a lot of room. Double or triple cellular blinds with side seals work really well. They are permanent and when retracted the blind does not take up a lot of room. The strings and internal hardware can be cheap and when they wear out its difficult to fix. I bought a slightly heavier duty style that has a corded rope loop that is much more durable. Here is link to what I am talking about https://cellularwindowshades.com/22-side-tracks-for-cellular-shades. These are custom made and in order to install the side tracks there has to be enough depth of the window frame to install them. I have a triple casement window of similar size and have one blind that drops down over all three with side tracks. These are not cheap but they make all the difference. I can sit right in front of them with my back to them on the coldest night and not get any drafts or radiant effects. They can transmit diffuse light even when down unless you buy light blocking shades which I use in my bedroom. The light blocking version has a foil barrier in layers and no light makes it through.

 

[SeanBB]

I have a small wood burner in my conservatory which has double glazed K glass and it gets lovely and warm. I do not have curtains in there because at night I enjoy looking out at my floodlit garden. I would much prefer to burn a little more wood than put curtains up.


http://www.thehomeimprovementcentre.com/double-glazing/pilkington-k-glass-is-it-worth-it

 

[SpaceBus]

Yes the radiant barrier is short term fix with some major caveats. Make sure the product is non flammable, if it inadvertently gets set on fire it will burn quick and most likely take the house with it. Unless you can get it tightly sealed against the window frames you will get a lot of convective flow between the curtain and the windows which can suck some heat out of the house. You also may have moisture buildup on the window frames, this can lead to water and possibly black mold collecting in the edges and the sash.

There are two longer term fixes. If you have sewing ability window quilts work pretty well but can have the same issues as the radiant barrier and when retracted they take up a lot of room. Double or triple cellular blinds with side seals work really well. They are permanent and when retracted the blind does not take up a lot of room. The strings and internal hardware can be cheap and when they wear out its difficult to fix. I bought a slightly heavier duty style that has a corded rope loop that is much more durable. Here is link to what I am talking about https://cellularwindowshades.com/22-side-tracks-for-cellular-shades. These are custom made and in order to install the side tracks there has to be enough depth of the window frame to install them. I have a triple casement window of similar size and have one blind that drops down over all three with side tracks. These are not cheap but they make all the difference. I can sit right in front of them with my back to them on the coldest night and not get any drafts or radiant effects. They can transmit diffuse light even when down unless you buy light blocking shades which I use in my bedroom. The light blocking version has a foil barrier in layers and no light makes it through.

Thanks for the link, I've been looking into shades for our windows. The insulated drapes work well for the sliders, but they need window boxes at the top and magnets on the sides to keep the seal well. My dog likes to go behind me and create gaps.

 

[Easy Livin’ 3000]

First, see old pic (no current pic), the stove now is under where the clock on the wall is, door facing the window. I'm getting ok burn times, around 5-6ish hours. Stove is rated for 8 hours. Anyways, I posted in the hearth section and am being told I'm loosing radiant heat, through the triple glass windows...and that curtains *may* help.

I guess I'm just struggling to understand how heat can go out tripe pane (non opening/no leaks) windows so well, but not fabric curtains. Would curtains really help?

What about a radiant barrier some like this: (broken link removed to https://www.radiantguard.com/collections/radiant-barrier/products/radiant-barrier-xtreme-metalized-insulation-xtr500b) I understand it wouldn't look great, but it would just be for winter and mostly at night.

Thoughts? Has anyone noticed a huge difference with better curtains? Thank you in advance.

Curtains work wonders. Our first year here without them, big burrr, second year and since, only little burrr.

It's been said before, but the radiant heat is just like the warm you feel in the sun. And sun goes right through the windows, doesn't it? I'd curtain up all the windows in that room, and put something that would reflect the radiation on the window directly in front of the stove. Won't look great, but it'll feel great.

 

[peakbagger]

I really need sun in the winter and set up my second floor bedroom/office with plenty of windows to the east and south as I have a nice view of the northern Presidentials in NH out the front window. When the sun is out in the winter I get the first rays of the sun. This is a good thing on a sunny day but not so good at night on cloudy days. A double pane window is R3 I started out with the regular cellular blinds without side seals (Comfort Tracs) and they worked well but cold air did spill out the sides and after about 4 years one of the strings broke. I sent that way to get fixed but the shipping out and back was crazy. About 2 years later I had another string fail on different unit and decided to fix it myself. Dumb idea as the parts in the headworks that are hidden away are cheap and threading the strings back through the . These weren't that cheap originally but I finally bought a new set with the more durable mechanism and the side seals and they are great.

One caveat is that the actual cellular blind is some sort of stiff fabric. I don't think it would hold up well to a dog or cat scratching on it, greasy fingers or dog drool. On the rare occasions I dust, I just use brush attachment on my vacuum and follow the ridges.

 

[EatenByLimestone]

I have insulated window shades that we got from blinds.com. You can really feel the difference in temperature if you slip your fingers around to the cold side. You can't leave them down all the time or mildew will form on the backs due to condensation.

 

[bholler]

I have a small wood burner in my conservatory which has double glazed K glass and it gets lovely and warm. I do not have curtains in there because at night I enjoy looking out at my floodlit garden. I would much prefer to burn a little more wood than put curtains up.


http://www.thehomeimprovementcentre.com/double-glazing/pilkington-k-glass-is-it-worth-it

Yes but are you trying to heat the rest of the house from that space.

 

[Kiotick4010]

High school physics.

Google radiant heat transfer.

There are three types of heat transfer. Conduction, convection, and radiation.

Those same windows allow the sun’s radiation to heat up the room during the day, especially on a bright sunny winter day. Covering the windows will reduce the sun heating effect just like the drapes reduce radiant heat loss from your stove to space.

 

[peakbagger]

In NH there is the White Mountain National Forest. the towns to the south are close to Boston and developers build vacation homes and condos and lay them out to optimize the view north. That means big glass walls of windows facing north. Might be great for a view but darned expensive to heat. My house is north of the Whites so my views and windows are facing south. When the sun goes down I close the cellular blinds and in the AM when the sun is up I open them. Even on a 20 degree day within about 2 hours I don't need any heat and it stays that way until sunset. For another $150 bucks a window I could buy a motor operator with photocell that would open and close them automatically. I like the KISS concept and do it myself.

 

[SpaceBus]

In NH there is the White Mountain National Forest. the towns to the south are close to Boston and developers build vacation homes and condos and lay them out to optimize the view north. That means big glass walls of windows facing north. Might be great for a view but darned expensive to heat. My house is north of the Whites so my views and windows are facing south. When the sun goes down I close the cellular blinds and in the AM when the sun is up I open them. Even on a 20 degree day within about 2 hours I don't need any heat and it stays that way until sunset. For another $150 bucks a window I could buy a motor operator with photocell that would open and close them automatically. I like the KISS concept and do it myself.

Our house is like this as well with additional passive solar wall built into the house. I am soon replacing our four south facing sliding glass doors from the 70's, but they did hold up pretty well all things considered. Our insulated drapes make the house much easier to heat and much more comfortable. Maybe it did need the old original defiant before decent window treatments! The rest of the old 70's dual pane windows are not long for this world. I think I'll save the glass for a green house if the casements let it go. I'm looking at the Marvin hurricane rated windows with built in shades, do you think they are better than the trick cellulose blinds you posted?

 

[EatenByLimestone]

The more complicated the window is, the more there is to fail.

 

[peakbagger]

I am not familiar with the Marvin product with build in shades. They are premium windows in general. Pella used to make a double pane with mini blinds built into the casing with a removable interior pane in front of the blinds.. I would avoid a window with shade in the double pane as it it acts up the window needs replacement unless they use the Pella approach. Great for sun but I doubt it would do much for R value. A typical double pane is around R 3.5 while a triple pane is R 5. Cellular blinds add around R 1 while the same blinds with side seals add about R 3. Some reports indicate the light blocking cellular blinds have a measurably higher R value compared to the non light blocking versions as the light blocking variety has foil barrier which is most likely acting as radiant barrier. A double pane window with a set of cellular blinds is probably R 6.5, I doubt the Marvin if its like the Pella probably at best may be R 4.5 if they are a hybrid of a double pane with what effectively is a fitted storm window with miniblinds. Therefore I think the cellular shades are most likely more efficient overall.

I think if it fits architecturally, the big opportunity is reframe the opening by raising the wall so the bottom of the new window is a couple of feet off the floor. This lower area is typically blocked by furniture anyhow and really makes a difference. Then again sliding glass doors are notoriously leaky so replacing them with conventional windows is big step up. Note crank out casements are more efficient than double panes due to least amount of seams and they usually are the best in high winds as the wind pushes them closed against the seals. They also have a better latching system.

Note I have skipped the discussion of all the various coatings and air barriers that can be supplied in between the panes. Some block UV form entering some block IR from leaving and there are various gases like argon that can be used to fill the space instead of air for a slightly initial R value that declines over time as the gas diffuses out.

There used to be some good brands of Canadian manufactured windows but I dint know any particular names, might be worth a trip over the bridge to see what they have and comparing it to Marvin.

 

[SpaceBus]

I am not familiar with the Marvin product with build in shades. They are premium windows in general. Pella used to make a double pane with mini blinds built into the casing with a removable interior pane in front of the blinds.. I would avoid a window with shade in the double pane as it it acts up the window needs replacement unless they use the Pella approach. Great for sun but I doubt it would do much for R value. A typical double pane is around R 3.5 while a triple pane is R 5. Cellular blinds add around R 1 while the same blinds with side seals add about R 3. Some reports indicate the light blocking cellular blinds have a measurably higher R value compared to the non light blocking versions as the light blocking variety has foil barrier which is most likely acting as radiant barrier. A double pane window with a set of cellular blinds is probably R 6.5, I doubt the Marvin if its like the Pella probably at best may be R 4.5 if they are a hybrid of a double pane with what effectively is a fitted storm window with miniblinds. Therefore I think the cellular shades are most likely more efficient overall.

I think if it fits architecturally, the big opportunity is reframe the opening by raising the wall so the bottom of the new window is a couple of feet off the floor. This lower area is typically blocked by furniture anyhow and really makes a difference. Then again sliding glass doors are notoriously leaky so replacing them with conventional windows is big step up. Note crank out casements are more efficient than double panes due to least amount of seams and they usually are the best in high winds as the wind pushes them closed against the seals. They also have a better latching system.

Note I have skipped the discussion of all the various coatings and air barriers that can be supplied in between the panes. Some block UV form entering some block IR from leaving and there are various gases like argon that can be used to fill the space instead of air for a slightly initial R value that declines over time as the gas diffuses out.

There used to be some good brands of Canadian manufactured windows but I dint know any particular names, might be worth a trip over the bridge to see what they have and comparing it to Marvin.

We are undecided on the sliders as two are upstairs with balconies and two are downstairs that open up to a deck. Sometimes we think about getting rid of the balconies (they actually need to be torn down and new ones built anyway) and just having giant windows, but having the ability to open the sliders during the summer makes us want to keep the whole setup And just update it. We are definitely going with casement windows as replacements for the old 70's sliding windows. The Marvin ultimate casement windows are wood with exterior aluminum clading and have various coatings and optional triple panes, same with the doors. The built in blinds are not a part of the glass and are on the inside of the window casement, but I don't think we are going to get them. I'm pretty sure the triple pane Marvin products are rated as R5. The insulated blackout drapes have an unknown r value, but do work for keeping radiant heat in. All of our current windows and doors are double pane, but installed in 1975, and dying.

I like the Marvin windows because they offer hurricane protection, we live on the coast of Maine, and also aluminum exterior clading. Everything else I've found is fiberglass or vinyl and I don't like either of those options. Noreasters are no joke, but I've yet to personally experience one. Our bathroom window actually cracked on the inside, so this has motivated me to invest in some seriously robust doors and windows.

 

[WinterinWI]

When are we going to get to see a picture of this mythical stove?

 

[firefighterjake]

We are undecided on the sliders as two are upstairs with balconies and two are downstairs that open up to a deck. Sometimes we think about getting rid of the balconies (they actually need to be torn down and new ones built anyway) and just having giant windows, but having the ability to open the sliders during the summer makes us want to keep the whole setup And just update it. We are definitely going with casement windows as replacements for the old 70's sliding windows. The Marvin ultimate casement windows are wood with exterior aluminum clading and have various coatings and optional triple panes, same with the doors. The built in blinds are not a part of the glass and are on the inside of the window casement, but I don't think we are going to get them. I'm pretty sure the triple pane Marvin products are rated as R5. The insulated blackout drapes have an unknown r value, but do work for keeping radiant heat in. All of our current windows and doors are double pane, but installed in 1975, and dying.

I like the Marvin windows because they offer hurricane protection, we live on the coast of Maine, and also aluminum exterior clading. Everything else I've found is fiberglass or vinyl and I don't like either of those options. Noreasters are no joke, but I've yet to personally experience one. Our bathroom window actually cracked on the inside, so this has motivated me to invest in some seriously robust doors and windows.

Usually any hurricane that gets up this far is pretty spent and is mostly a high wind and rain event . . . It's been a very, very long time since we've had a truly destructive hurricane up this way.

 

[SpaceBus]

Usually any hurricane that gets up this far is pretty spent and is mostly a high wind and rain event . . . It's been a very, very long time since we've had a truly destructive hurricane up this way.

By hurricane I really mean Noreaster. We get winds at my house over 40 MPH somewhat regularly, so far at least. A friend of mine a few miles down the road had a plate glass window explode from the wind.

 

[SpaceBus]

My phone actually just informed me that there is a wind advisory for tonight. Gusts up to 50 MPH coming from the southwest.

 

[Sawset]

Light is a form of radiation. It goes through glass windows. Even the best ones.
Just to add some clarity to the subject.

 

[peakbagger]

The other option I did at my retired parents house was cut foam faced iso board foam to the size of the window casings and just put the foal in the windows in the unused section of the house behind the shades in the winter. The windows were single pane with a storm window and the foam made a big difference. Years ago maine PBS had series on deep energy retrofitting a older Maine home. They actually made interior shutters out of Isofoam covered with fabric. When the sun was set, they would just close the shutters flush in window casement and open them back up in the AM.

Plenty of ways to cut down heat loss through windows but not so easy if you want to look through them. Greenhouse use a double wall polycarbonate sheet to let in light but also have some R value. They aren't glass clear and eventually get cloudy but do last quite awhile.

I guess if someone wants the outside view high R value and low radiant loss they need to hang a big screen TV on the wall and tie a camera feed to it