high heat on a double pane window???
popawheelie
| Posted in Energy, Heating & Insulation on
I have a window that faces south that is a double paned window. I don’t care if it is blocked off completely from the inside. For appearances I can just hang a curtain over the inside.
I get a lot of heat gain through this window and was thinking of insulating the inside but am concerned about overheating the window. I read here about windows loosing their seal because of high heat. I’m not sure if that was the cause or if it was just a bad window.
Can I put some foam board inside this window to cut down on heat gain? Will it over heat the window? I can hold the foam board back a few inches from the glass if that matters.
Replies
You're better off putting up a heavy duty roll-up shade. It'll reflect a maximum of light back out and will allow for convective ventilation between itself and the inside of the glass.
The best way to avoid heat gain is to build or install an awning, to keep sunlight off the glass. I built gable end awnings which match the roof, over all of the windows on this house which face south and west.
The awnings shield the entire window from direct sunlight. The effect on heat gain is excellent.
I agree that the awning would be best and might do several on that side of the house in the future. I do want them to look right so it would be a fair amount of work. It would be another small project and I have a lot of them.
In the meantime I would like to put something on the inside. Why would a heavy roll up shade be any better than foil faced insulation board? I know I didn't say foil faced insulating board in my first post but that is what I meant. It has the foil on one or both sides and I can cut it to fit snug in the casing about 4" away from the glass.
Will that make the glass to hot? From what I can tell ( not much) they are lower end vinyl clad windows.
Are they double-glazed? Low-E?
If they are low-E, adding another low-E surface (the foil) will create a double-mirror effect which will trap heat and likely accelerate the demise of the windows.
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They are double paned windows but i don't think they are low-e. Just run of the mill low end double pane windows.
Why would a heavy roll up shade be any better than foil faced insulation board? I know I didn't say foil faced insulating board in my first post but that is what I meant. It has the foil on one or both sides and I can cut it to fit snug in the casing about 4" away from the glass.
I'm not sure that the foam insulation would cause problems. Maybe a good idea would be to try it as you describe, with a thermometer in that space, so that it can be read from the outside.
I'm going to re-think this. I can do something on the outside for now. I think the temp would be to high if I sealed up the inside.
The window is on the side of the house so it won't show much and this is a temporary fix until I build an awning for it.
If I use foam with a neutral colored siding material on the outside it won't look so bad and will work.
Thanks for all the ideas!
Here's a photo I just took of two awnings I built on the west side of this old stucco house. They match the 5/12 roof. One projects further so's to provide shade for that taller window.
Edit: I'll have to search for a thread on how to reduce the size on that photo.
Edited 3/11/2008 12:37 pm by Hudson Valley Carpenter
Those are huge! Both the pics and the overhangs. I don't think you could call them awnings. More like small roofs ; ^ ) By the way, they look great!
I'm not sure what roof style I'll match yet. I have a typical gable end comp roof above and I'm just finishing up an attached storage shed with a corrogated roof down below. I'm leaning toward the corrogated roof because it will be easier but I don't want it to look trashy. I was thinking along with the awning I could make a storm window to go over the one I don't need to open. It will still look like a window but the storm should help.
Edited 3/11/2008 1:45 pm ET by popawheelie
I don't know what to call 'em. I can't remember seeing anything quite like 'em either so I just call 'em gable end awnings. The near one is about three feet off the house and the other is four feet.
Anyway they shade the windows while not obstructing the view, like most aluminum awnings do. There's five of them on the house.
Here's another.
I'm not sure what roof style I'll match yet. I have a typical gable end comp roof above and I'm just finishing up an attached storage shed with a corrogated roof down below.
The ones I built were pretty simple, though time consuming. I made up three trusses with plywood gussets for each awning. That made them easier to build, single handed.
If I were to do another one I'd build a full scaffold for it. At the tim it seemed like it should've been easy to do off a ladder but there was just too much up and down, moving around.
Like most projects I underestimate how long they will take. I'm the same way. My situation is different than yours. That side isn't seen as much and I've kind of dedicated that side of the house to storage sheds, utilities, solar panels?, who knows? I'm doing it a utilitarian high tech look. Like I said, it is very visible.
Yep. I understand. The east side of this house, the least visible side with windows which are only meant to bring light into the rooms...that side I used slatted aluminum awnings. Very easy to install and not too expensive, from HD, IIRC.
I'm going to HD right now so I'll check. Thanks.
OK. I think I got it.