Insulating Aluminum Frames

Old 11-19-07, 06:41 PM
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Insulating Aluminum Frames

How can I cover or insulate the "aluminum frames" on double pane windows?

The house is 1.5 years old and has aluminum frames that conduct cold and enable condensation. I hoping for an alternative to replacing all of the windows.

Is there a plastic or wood coating that can be put on the frames; inside or outside that would provide some insulation?
Old 11-19-07, 07:40 PM
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Sad to say, your idea would be quite difficult to impliment, and would not make a measurable difference in heat loss. It's too bad contractors continue to install aluminum windows- even ones with a thermal break- in cold climates.

The product you need to cover your windows and help prevent those cold drafts has already been invented: 3M window insulation kits. (basically a cheap, plastic, makeshift storm window that you install on the inside of the window.)

And speaking of storm windows, even certain double pane windows can benefit from a storm window- either interior or exterior, depending on your setup. Most people prefer to get rid of their storm windows, or installing storm windows over windows that already have double paned glass, but they really can help- mainly by acting as a buffer to the wind and cold. I certainly am not an advocate of storm windows, but more and more you find people (esp in colder northern climates) complaining about condensation, icing, etc and are unsatisfied with their "new double pane windows", saying that they never had those problems before they replaced their windows. Well, there is some truth to that, mainly because of the benefits of a storm window.
Old 11-20-07, 07:05 AM
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One of the truly sad ironys of window technology is that if condensation is forming on your windows, the windows are actually doing their job. They are keeping cold air from penetrating and warm air from escaping (or visa versa in the summer) Just remember when conditioned air escapes, $$$$ are literally flying out of your windows.

Condensation is a symptom its not the problem. The real problem is the humidity level inside the house is too high. Just like the weather person says, when the warm front
slams into the cold front, there is going to be a storm.

As for aluminum conducting cold, try a little test. First pick a room that has been unoccupied for two hours. (The time really dosent matter its just for drama) Go into the center or as close as you can to center. Pick any room. Record the temperature. Then, put your hands on a wood object (like a chair). Then put your hands on a fabric covered item, (like a sofa) and finally put your hands on a metal object . Which is colder?

If you said the metal object, or any other object for tha matter, my question is how can that be. If the room temeperature is 70 degrees, then ALL of the objects in the room are 70 degrees. If they are all the same temperature then how can one object be colder than the other. They can;t conduct cold that isn't there.

There was no real point to that test, just thought you'd find it interesting.

You actually have a number of choices, as Xsleeper suggested, you can always attach storm windows either inside or out and as long as they are separated from your primary window they will act as a thermal nsulator.

Personally, my first choice would be an inside storm window system, because when you want to remove the sashes, it will be much easier. I would also use a single lite (picture window type if for no ther reason than asthetics) If you would use an outside storm window, you have to make sure that the sash is smaller than the opening or they would need to beoutside removable, not very practical on a two story building.

Another option is to lower the humidity level in your home.
Try these steps to lower humidity in your home

If you use one, turn down or stop using humidifier.
Use range and bathroom exhaust fans while cooking and bathing or open a window for a few minutes to bring in cool, drier air. Cook with pans covered. Take shorter showers with cooler water. Install a fresh air intake duct. Outside air introduced into the home lowers the humidity level. Reduce the number of plants in your home or water them less; they release water vapor into the environment. Vent clothes dryer to the outside. In tightly insulated homes, consider installing an air-to-air heat exchanger.

In your case, new windows will only cost you more money.

And, finally don't be impressed that your have double pane
glass. It isn't the glass that is insulating, it is the deadair between the glass that is insulating. ( ever wonder why condensation does no form on the inside of the outside glass?

Anyway, lower the humidity and you'll stop your problem.
Old 01-01-08, 08:19 PM
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To get back to the original question: "Is there a plastic or wood coating that can be put on the [metal] frames; inside or outside that would provide some insulation?" I am writing this is in a Northern Virginia January.

I have a sliding glass door and five sliding glass windows. All are double-glazed metal frames and none have thermal barriers to insulate the inside and outside portions of the metal frames. I have no problem with condensation. But put your fingers on the inside glass and then on the inside metal frame and there is a big difference. The metal is very cold.

Short of replacing all the windows and doors, or installing storms (not an option for the glass door) is there anything I can do to stop the heat loss from these frames (or cooling loss in the summer)?

As a experiment, I bought some narrow wood trim stock and am looking at using double-stick tape to attach it to the frame of the glass door. But I have been warned that the temperature changes will make the double-stick fail. XSleeper says it would provide no real benefit, though I am not sure why. It seems to me that this is an engineering problem waiting for a solution! Surely there is money to made here by some clever soul.
Old 01-01-08, 09:09 PM
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My comment was: "Sad to say, your idea would be quite difficult to impliment, and would not make a measurable difference in heat loss." It was a polite way of saying that this isn't a realistic idea to pursue. Here is why:

By saying "difficult to implement" I think it would be difficult to cover every square inch of the interior side of the aluminum frames and sashes. And by "interior side", I don't just mean the side that you see when standing 10 ft away from the window. Covering just the faces of the frames would be pointless. Interior sides of an aluminum frame (the insides of the top jamb, left or right jambs, sill jambs that are exposed to the interior of the home) conduct just as much heat out of your home as the front side does (the side facing you). Assuming your "sliders" slide left and right, covering the faces of the slider sashes, and the meeting rails, would make the sashes impossible to remove, since they need to be lifted up and out to take them out of the frame.

Sure you could stick wood onto the aluminum with double-faced tape on the frames. If you get the right sort of tape, it'll hold plenty. A glass shop would provide you with the best kind, the sort that is used when installing (glazing) insulating glass units into various types of windows frames. But I feel sorry for the poor sucker who wants to clean all that tape off the windows someday. It does NOT come off.

Rigid XPS foam insulation is R-5.0 per inch. That would be a decent improvement. ASSUMING 1/8" thick double-faced tape would have roughly the same insulating properties as XPS (a big assumption), the tape itself would be R-.625. Wood has an r-value of roughly R-1.20 per inch. So let's say you plan to stick 1/4" of wood onto the double-faced tape. That would be R-.30 Add that up and you have R-.90.

That idea is a lot of work to increase the r-value by .90 on only "some" parts of the frame.

Aluminum frames conduct thermally from heat -> cold, not the other way around. If you cover the aluminum with wood, the wood WILL feel warmer to the touch because even 1/4" of wood has a better r-value than aluminum does, but it will not change the fact that heat is still being transferred from heat -> cold behind your proposed facing.

If your interior temperature is 70F, and it's 20F outside, heat will leave the house.

If you put some wood trim on the aluminum, and the wood trim somehow manages to stay 70F, and it's 20F outside, the same exact amount of heat will be leaving the home through the aluminum frames... except for the miniscule R-value of the tape and the wood, which I would GUESS to be .90. (and even this would assume that 100% of the aluminum is covered)

Therefore IMO, I feel it would be a pointless waste of time. But if you'd like to try it, knock yourself out. But like I mentioned, just because the wood will feel warmer to the touch does not mean that you are losing any less energy out of the home. As it's been explained to me, it's not that cold is coming INTO the home... heat is LEAVING the home, which is actually what makes the frame feel cold. That's just how metals work, they dissapate heat, conducting it from heat -> cold.

If others have an opinion, I'd be glad to hear it too.

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