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smbpowers
below grade glass block windows

We are wanting to replace our below grade basement windows with glass block (our window wells fill with water--bottom up and leak through the slider windows that are there.) We have gotten a couple of estimates. One said they just use mortar and is half the price of the other. The other says they use mortar and come back and remove some of it on the outside. Then they apply a sealant of some sort which allows for movement of the foundation and prevention of cracks in the mortar, emphasizing this is important for below grade installation. I would like to know if this is really necessary and worth paying double.
We orginally tried to dig out the well some more to try to prevent leakage but were not successfull.
Any ideas would be greatly appreciated!

A. Spruce
Re: below grade glass block windows

Do the wells fill with rain water/surface water, or is the water collection due to a high water table?

smbpowers
Re: below grade glass block windows

It seeps up from the bottom of the well so I'm guessing high water table?. We've tried the well covers and they didn't make any difference.

A. Spruce
Re: below grade glass block windows

Bummer!

Here's my opinion. The foundation/basement wall shouldn't be moving, if it were, then there'd be cracks and most likely leaks within the basement. That being said, then there should be no movement within the window opening either so that an elastonumeric grout shouldn't be necessary. Along with that, removing a bit of the grout from the outside and installing a sealant isn't going to provide any flex, what this will most likely do is seal the grout to the existing concrete, which you'll need to do anyway, with or without the removal of grout.

smbpowers
Re: below grade glass block windows

Does it matter if the house is only 2 1/2 years old and might still be settling?
Thanks!!!

A. Spruce
Re: below grade glass block windows

There's a big difference between the house settling (that's a framing related issue ) and the foundation moving (not set properly/deep enough/etc ).

If your foundation is moving, you're going to see cracks in it because concrete does not flex or like to move. The only way that the house settling is going to affect the size of the well window opening is if it protrudes up into the framing, even then there should be negligible movement at the window itself because the weight should be framed and supported around the window, not by the window.

canuk
Re: below grade glass block windows

Sounds as though there is an issue with the window well drain system that should be addressed before going through the expense of replacing the window.
In the attached photo the white " T 's " are a drainage system that's commonly done around here. These are extended up into the window wells and tied into the perimeter drain system.
Many times window wells are simply back filled soil with a thin layer of stone that eventually gets contaminated with debris preventing draining.

Now this being sight unseen .... it raises the question of putting out money in the wrong place. While replacing the slider window with glass blocks may prevent water leaking in .... this really isn't addressing the problem of the window well filling with water.

2 cents worth.

calcats
Re: below grade glass block windows

Have you considered the possibility of a french drain going from window well to window well and then away from the house. The drain should be below the sill of the windows. This may not completely solve the problem due to its being a ground water problem but it should keep the level of water below your windows. Just some food for thought. Good Luck.

Calcats ;)

smbpowers
Re: below grade glass block windows
canuk wrote:

Sounds as though there is an issue with the window well drain system that should be addressed before going through the expense of replacing the window.
In the attached photo the white " T 's " are a drainage system that's commonly done around here. These are extended up into the window wells and tied into the perimeter drain system.
Many times window wells are simply back filled soil with a thin layer of stone that eventually gets contaminated with debris preventing draining.

Now this being sight unseen .... it raises the question of putting out money in the wrong place. While replacing the slider window with glass blocks may prevent water leaking in .... this really isn't addressing the problem of the window well filling with water.

2 cents worth.

So here's my question on the french drain. When we tried to dig out the window wells some more we ran into the french drain (about a foot or so from the bottom of the window) which was just the black accordian type tubing with holes in it. Is this what it should be and where shoud it be running to? If I'm supposed to see where it goes to, I don't. From what I saw of my house being built and the neiboring houses I did not see anything like the tubing set up that was in your attached picture.
I'm willing to do the work to correct the problem, digging out or whatever. I just need so advice to point me in the right direction. I would rather break a sweat then the bank on new windows.
Again any advice would be great. I really appreciate everyone's help! Thank You!

calcats
Re: below grade glass block windows

Check the old french drain, is it full of debris? The way I would do it is to dig a trench one foot deep, below the sill of the windows, going from window to window and out the end of the house. Put 3" of #2b stone in the bottom, place a 3" perforated PVC pipe in the trench with the HOLES UP (some people do it differently, but this has always carried a lot of water for me in the past). Cover the pipe with 3" of #2b stone again and then cover the stone with 15 or 20 lb. feltpaper. This will keep the soil from clogging the stone. Now put 3 or 4 inches of topsoil on top of the paper. This should keep the water from reaching your windows. Good Luck, hope this helps.

Calcats ;)

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