Hi Glenn,

If they are cloudy between the panes it is almost always and indication of "Seal Failure". If the windows are still covered under a 10 year warranty you should first contact the window manufacturer. They may provide a service provider to install the glass as well as providing the glass itself. You may want to hire a pro to do this job. If you are in the Kansas City area, we do this work on most brands of windows.

If you plan to do this yourself you'll want to invest in a suction cup from a glazing supplier, or rent one from a tool rental or local glass supplier. This will make lifting those big glass units a lot easier.

Depending on what type of window that you have, there may be a trim piece that is removable around the glass and attached to the frame. If so, you'll need to carefully remove it to replace the glass. I say carefully because you may want to re use it, or if it is wood you might just want to replace it. Thes stops may be either on the interior side or the exterior of the unit.  Once this is off, you'll need to cut around the silicone adhesive or tape that is holding the glass in. Run a knife or a flat blade between the glass and the frame to seperate it. Some units may have a flexible boot that goes around the perimeter that will be removed and reused. Once the glass is out, scrape out any remaining sealant or tape and apply setting blocks on bottom and sides of the frame. Apply a bead of sealant to the perimeter of the frame where the glass is going and install the new glass units. Install the stops back around the glass. Once it cures, you can water test for leaks.  

Hope this helps.  

Doug Bennett / President,  All-Weather Windows Doors and Siding , Inc.

I agree wholeheartedly with the excellent answer provided by Christi at Callen Construction that your problem is probably caused by the different coefficient of thermal expansion of the materials involved.  And yes a fiberglass window would be a good solution, but a wood window would also solve the problem.

To put some numbers to the expansion and contraction properties of window material, with 10 as the worst performance and 1 as the best, here's how they stack up:  vinyl - 10, composite (like Andersen Renewal Fibrex) - 4.5, actual fiberglass (like Pella Impervia or Marvin Integrity) 1.4, wood 1.0.

Don't discount a clad wood window if you like the aesthetics- it will perform well if properly sized and installed.

Hi Peggy,

The difference really varies based on the existing windows. For pricing purposes, you could add a couple inches to the L and W. However, DO NOT order windows based on those numbers.

Glenn-

I agree with my colleagues that you should hire a professional to do this.  Contact the manufacturer and see if they will install the glass, what the cost is, and how long the installation warranty is.  If they won't or it's too expensive, find a local professional with a home improvement license.

You say it's a vertical wall but it's on a roof?  If it's a window in a vertical wall find a window installer; if it's on the roof with flashing and shingles surrounding it find a roofer.

It may look easy, but trust me it's more complicated than it looks.  Installing it may be simple but ensuring it doesn't leak for the next 20 years takes some experience.

If you're a DIY guy, find someone who will let you help but will oversee the job and WARRANTY the installation.

Good luck

Joe

Edgar makes great points of matter in regards to the window selection and the Point of Insualtion. We SPray Foam Every New Home and are extra focused on sealing the envelop properly. We are located in a sub tropical climate and the principles apply adversly although nearly the same.

We ar eable to achive Power bills from 60-160 dollars on homes from 2000 sqft to 6500 Sqft. Air Loss, Insulation, and proper install of product

PROTIP: Watch ou twith the Term "Builder Grade" A Seasoned Window and door expert from Lowes will educate You on who makes the  "Builder Grade" windows You might speak of. There is a lot of " Razzle Dazzle in Windows and doors"

Check the performace & Rating. Do Not get Oversold and get a solid warranty orinated window.

Remember if they are not installed correctly and sealed IT does Not matter.... air flow is air flow... Loss =Loss

Billy Gavigan

Great Question!!

About $3,500 -$4,000 trimmed out inside and out.

You might want to have a energy assessment done through a program such as Home Performance with ENERGY STAR or a utility-specific program in your area. WIndows often cost a LOT (for a quality product) compared to the amount of energy they can save. So if they are physically falling apart, you definitely need to replace them. If you can't open them, its a problem! If air blows though them, its a problem. A little frost is commen in a northern climate. A qualified energy assessor can help you determine the value in replacing them compared to other things in the house that you might also need to fix and not even know about! Air leakage is the biggest source of heat loss in most cases, and needs to be fixed before insulation can be added.

Hey Jerrod, 

When installing replacement windows, the existing window frame remains and the replacement window is installed inside the existing frame.  This causes the glass area to shrink slightly to accommodate the new window.  When installing a "new construction window", the entire window unit including sash and frame is removed down to the rough opening and the complete assembly is replaced which includes a nailing flange which has to be secured to the exterior wall.  Installing new construction windows is a much more complex project since the siding on the exterior has to be removed in order to secure the nail flange to the wall.  Most consumers go with the replacement window do to the ease and cost of installation as compared to the new construction window option. Hope this helps!

Eric, Arocon Roofing& Construction

The best thing you could do for your home to keep the warm in and the cold out is to 1st. check your insulation in your attic if your not properly insulated the heat will escape. Another is making sure your windows are secured and latched. and proper weather seal is on your doors so draft cannot come in. 

I would recommend starting with making sure all the existing windows and securely closed and locked.  I find windows partly open because they have been painted that way.  Take some time to make sure each window closes properly add weather stripping as needed.

Add wather stripping to all doors

check that all the heating ducts are connected securely

Expansion and contraction, as mentioned previously, is a big driver of sealant failure.

The other part that was not discussed in moisture content.  Brick is largely moisture open and capillary draw of moisture will keep the brick wet and can cause the sealant to fail. 

If the home is new construction, the sealant that was used is cheap in most cases and was probably poorly applied.  Sealing large gaps requires the application of backer rod or some sort of backstop to apply the sealant to. 

The expansion rates are different for different materials but they aren't as dramatically different from one another often thought of. 

For example, Fiberglass is often touted as a much better material because of its more analogous coefficient of linear expansion with glass than vinyl.  That is true but it is not 7X less likely to expand than PVC.  More like 2X in most cases. 

Wood has a verly low expansion rate as related specifically to temperature but is moisture driven as Christi was referencing with the humidity statement. 

In my personal home which has high quality windows, we also suffered condensation. We generate moisture by breathing, cooking, and bathing. If you have casement windows with screens on the inside, you might be surprised just how much those screens prevent convection airflow and keep cooler air closer to the window glass. We solved the problem in our home using a combination of 3 actions.

1) We remove our window screens every winter.

2) We open our window shades all the way every morning and leave them open all day long.

3) We have timers on our bathroom fans and run them for about 4 hours per day in addition to the 10 or 20 minutes of bathing time.

4) Bonus: We always run our kitchen vent fan when we are cooking to remove moisture (and odors) from the house.

I hope that helps. In the end, it's all physics. It's about the dew point, which is the surface temperature at which the relative humidity condenses. It can happen with cheap or expensive windows.

By the way: If there is air leakage around the window, this is going to exacerbate the problem. So doing a call-back to the installer or a 3rd party energy-rating company would help if the other solutions don't work.

Cheri,

Did this just happen three years after installation or could this have been there from the time of installation and you didn't notice.  Sometimes this can happen, especially on older homes that have old wooden windows where the installers use something like a chisel to literally "bust out" the old exterior blind stops on the window when installing replacement windows from the exterior.  The old wood can be very dense and hard to chip off.  The force of hitting on the exterior could cause this type of thing or as someone else said, could have a shim putting pressure against the back side of the interior trim.  You probably would have noticed that kind of damage right away though.

Typically a 70 year old house has already settled so you wouldn't think that was the cause, unless you are having some other kind of structural problems with the home.  If it were water, I would imagine you would see some kind of staining or drips on the interior as well.  

It's really difficult to say, unfortunately.  It could be installation related, but would be hard to say without pulling off the metal wrap on the exterior (assuming they were wrapped) and seeing what is going on.