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Basement skylight well, instead of window well

R_C_Peterson's picture

I was wondering if anyone has tried this.  I'm reinventing the basement window well, ditching the clear plastic clam shell.  I want to make the window well into a mini-addition to the room, like a window seat, and move the window up to the top instead, as a skylight hatch or roof casement window, thus turning it into a skylight well.  This will be for a bedroom, so IRC egress requirements need to be met.   I think I'm good, but I've never seen anyone do this before, so I wanted some advice.  Please look at the attached image.

I posted the same on (post #207744, reply #1 of 2)

I posted the same on and it started a great discussion.  Basically, here's what folks agreed on in terms of the IRC code requirements: 

Per R310.1 we may call the vertical interior opening a windowless EERO and my windowless sill is <44" to finished floor. Then, the finished interior of the window well is minimum 9sf, 3'x3', per R310.2. Since it's not deeper than 44", no ladder needed per R310.2.1. And, lastily, the skylight-hatch may fit into R310.4 "Bars, grilles, covers, screens or similar devices are permitted to be placed over emergency escape and rescue openings, bulkhead enclosures, or window wells..." As long as it meets the minimum opening R310.1.1 with no operational constraints R310.1.4.

Additionally, it was cautioned that a child who otherwise might be able to open a normal window with a 44" sill, might have difficulties swinging open a skylight hatch 44" overhead and keeping it open.  Therefore Recommendation: hatch lift supports.

It was also cautioned that heavy snow accumulation would prevent opening the hatch.  Therefore Recommendation: Don't build this design in areas with frequent and heavy accumulation.

R_C_ (post #207744, reply #2 of 2)

You pretty much got the code interpretation at that forum.

Add your common sense with maybe a mockup (at least of the space and elevation) and a hatch the weight that pc of insulated glass will add to the lift-make sure you can operate it in a crouch of 44" and you should be good to go.

I know of a couple of earth sheltered BR's below grade that have a casement window and a slab w/ steps up to that grade.  Elongates the well, but simplifies the window and operation.

However, if for your comfort and aesthetics you wish a raised "seat", have at it.

Best of luck.

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