question about placing windows in the foundation

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diymirage

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(sorry Mods, i know this is probably not the right spot, but im dealing with this RIGHT now)

so, i had a company come out to install a basement window (48X48)

they came in and cut a section of foundation out, which leaves the bottom of the window level with the grass, but 3 feet about the basement floor

now, there is about 9 inches of foundation left above the cut out and they say it does not need aditional support

i think it does, and i thought (i know, key word) this was included in what the contract calls "prepping the hole for window"

the work is stalled now and were stuck on whether or not it needs a beam or some other form of support about the window


anyone have any experience with this?
 
I only know that in new construction there would be precast lentils or similar installed above all predetermined openings. Remodelers don't always adhere to standard practices and codes. 48 inches square is quite a large hole. Is there a window with so much iron frame structure? I don't know.
 
im not sure what frame the window is made of (i know its the wrong color, actually, its TWO wrong colors, but thats the least of my concern now
 
I agree with Ben. If this is a block foundation, it would seem to me they could notch out above the window and install a lentil, BUT, that would mean dropping the window down a row.. When I was doing block construction many many moons ago, every opening got a lentil.

IF it's a poured wall, it might be different.

Check your local codes.
 
In building my basement foundation, (the lentils are longer than the opening below ) the blockwork beneath the lentils ends was rebared and core filled. Something has to hold the lentil up too after all.
 
At the very least you should have had a 4"x6"X1/2" angle frame welded inside the opening,secured to the wall. Was there an x ray of the foundation wall before work began? If not you have no idea if it will support a 48" cutout. Is it in an area where the band board has been doubled?
 
What kind of foundation? Is it a load bearing wall? What is above it? Wooden frame and siding, brick veneer, log cabin, modular?
 
What kind of foundation? Is it a load bearing wall? What is above it? Wooden frame and siding, brick veneer, log cabin, modular?
it is a poured concrete foundation, 8 inches wide and reinforced with rebarb

semi load bearing, the floor joists run paralel to it
one room above it, then the roof slope

not sure on the frame, but wood siding, under vinyl siding
 
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So you have three floor joices over the window, and three trusses over the window one story above? I'm assuming 16" on center?
 
ok, im a dummy, the joist run PARALLEL to the wall, NOT perpendicular
 
So, if it's just one story and a couple trusses which really don't bear directly on it. And assuming there is at least two pieces of rebar in the concrete. I think you'll be fine. Consider this; had you put that window in there when the foundation was poured, they would have simply built a form the size of your
Window and poured it. Leaving 9" above.
 
yeah

i asked a few different people (unrelated to those who cut the whole)
one of them a concrete pourer, one of them a home inspector, one of them a buddy of mine who does general contracting

the first two said it will be fine, but my buddy thought it needed support
 
If the home inspector is the building inspector from your town or city he should know the building codes.

You said your wall is a poured wall. It should have a grid work of rebar in it
Vertical and horizontal. The horizontal rebar should strengthen it across the top of the window like a lentil. If it was a block wall you would use a lentil because most of the rebar runs vertically through the void of the block.
The block does have anything to hold it up.

Here's a little picture. I did a little editing of it for reference.
g01700art01.jpg

If the company you are having install it do this all the time you'd think they should know what they are doing. Of course that's not always the case.
If you still have doubts get a hold of the town or city building department to find out the building code for this type of project.
 
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