Cellar Door Greenhouse Windows

Introduction: Cellar Door Greenhouse Windows

Old steel flip-open single cellar door, where underneath collected cobwebs on the dark, rarely used concrete stairs... I built these window frames from 1x2's, a handful of screws and glue, and I salvaged glass from some old storm windows for the panes.

It brought light to the stairwell and greatly to the basement, and with a screen will provide crossflow in the summer. Fortunately the door is located on the south and west side of the house, so optimum for light and breeze.

The frame and glass are light enough that they  go up and down with the door.

The 1/2 wood stock fit perfectly in the flange. The front window had to be slightly trapezoidal, wider at the base, I used small plywood gussets at the narrow angle end.

It is much more weather-wind-airtight than the original door. For the back edge a length of foam pipe insulation fit perfectly.

Simple, pretty and inexpensive. About 3 hours of actual cutting and assembly, but years of staring at it wondering how to fix it.

Picture 1: Functionally finished. Glazing in place, unprimed. Glazing has to harden a bit before painting. I did traditional glazing using glass, glazing points, and glazing compound to bed and glaze the panes. The additional weight of the glass is altering the counterbalance springs, but it still opens easily. A steel door can be slammed, but a stickframe glass structure is inherently fragile, so it gets handled more gently. 6 small screws through the flange attach the window to the lid.

Picture 2: It opens like this, nicely. Plenty of headroom still, although these are steep stairs, not for regular use, which is why I rarely use them, but in the event I need to, this entrance works. Note that it stays up unpropped. The prop arm is not connected.

Picture3:  Actually the first step.  Basic frame built inplace, Covered with visqueen temporarily. Stood on it easily with all my weight. No you don't jump on roofs anyhow. Roof has plenty of slope for snow and rain., Front window slants in at the bottom, providing its own eave. The steel lip serves as drip rail.

Picture 4: The tools, screws, glue I used, Plus glass scraps, a bundle of 8foot 1x2 white pine, oh and of course a chopsaw.  The screws are "Stop-Split" #1 square drive #6 1-5/8inch flathead wood screws, which are kinda like a self-tapping screw and are kinda hard to find. The are a little long, and some points need to be ground off on the outside. Standard gold screws work, but cause a lot of splitting. Using screws allow glued assembly in place, tight joints, and compensation for things like a bowed front sill. This was a pretty close fit, even the thickness of the plastic made it fit a bit tighter. Testing the opening/closing regularly assured nothing was wacky out of line.

Glass cutting is surprising easy. Always just buy a new glass wheel cutter. Score smoothly and assertively at a constant speed with a firm touch. You can trim surprisingly thin strips from a fairly long edge of lightweight window glass. I rough cut the class oversize and held it in position to mark with a Sharpee for final trim cuts.

Pictures of the inside do not do it justice, (Pic 5) but it addds significant light to that section of the basement, and it is now actually an inviting nook, in a shop guy kinda way. I can work there during the day with no need for additional light to read fine print.

The small triangle windows will get screens and hinged awning glass framed window inserts, to improve summer ventilation. They are high enough from the ground that splash and critter incursion will be avoidable. It's not like it's a dining room, anyhow.

When I find one, 42" wide fullview door twill be put in the bottom opening, to allow light but keep cold out in winter.

It's a good place to spy on rabbits on the lawn.

Thanks for looking. Any questions feel free. Have a sunny day.

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    2 Discussions


    6 years ago on Introduction

    going to try it, how did you attach it to the door? glue? does it close on it's own or do you have some type of clamp down there.? Got a cruddy door there now with no insulation.


    Reply 6 years ago on Introduction

    Drilled little holes though the vertical flange, screwed it to the frame. This one has a spring "counterweight". The additional weight of the frame and glass holds it down, and I tied it off with wire on the inside for security.

    Basically it's 2 layers of 1x2 frame. I made one layer, flat, that fits into the upper flange and meets the lower edge. Assembled the three sides of that and put it in place, then tacked/glued the inner layer so I'd have a corner to set the glass in.

    It's not square, slightly trapezoidal narrower at top. I glazed in the glass after it was all assembled and the glue dried.

    The bottom is not flat either. By screwing the top to the door, and having vertical mullions, I was able to pull the bottom crosspiece up into a curve that matched the base front step. It's a total freehand job.