Vent solutions for a Basement window?


Hi all,
Due to temperature issues, I’m moving my whole Forge operation to a basement room, forcing me to rethink the venting plan. (no, I haven’t even plugged my Forge in yet; don’t get me started…) Long term, I’ll be running a real vent through the wall, but for now I want to just do it through one of the windows. These are basement well-windows (I’m sure there’s a real name) with the wells capped with clear plastic rain-caps, a necessity (kind of looks like a half-igloo).

So the plan is a little more complicated than just pulling out the window and replacing with a (short term) sheet of plywood or (medium term) plexiglass with a 4" hole and the vent connecting through that. That’s all well covered in other posts.

What I’m noodling is the well-cap. Again, I need it or rain will definitely pool in the window well (bad). So two options I see: #1, ignore it and just vent right into the covered well. I seriously doubt it’s airtight… but I really am uncomfortable with the idea of filling that little space with exhaust. I also suspect I’d get back pressure on the line to some extent, limiting the effectiveness of the venting.

#2 is to cut a hole in the cap and run the vent through it, vertically up a little ways, and then end it with a right angle and one of the standard vent hoods to keep water out. I can secure the vertical run to the house wall, and would have no worries for back pressure etc. The trick is that the cap is basically a quarter-sphere of somewhat flimsy clear plastic, and so cutting the hole for the venting to run through and then sealing it against rain getting in the well has to be done right.

I’m leaning toward #2. But I’m very interested if anyone has done anything similar and has suggestions? And pictures?


Something like #2? Or, depending on how the well cap is placed and how much roof there is over it, can you just move it out from the foundation a bit or up a bit to give airflow? Or cut a flap out starting at the house edge?


Thanks for the thoughts! Moving the cap out away from the house isn’t a good option here; there is basically no roof overhang and the well is sort of surrounded by the deck, so there’s no room to come out in any case. Im picturing the flap cut kind how you are describing, but it’s the resealing the vent pipe to the cap that’s a big concern. I’d like it not look too terrible so my first thought (marine tape the heck out of it) is not desirable. That would look awful. Not sure how best to marry those two pieces. I should add that I was thinking of using PVC for this part of the vent.
But again: open to suggestions.


How about a picture of the bubble? That would help generate ideas that won’t look bad.


That… would have been a good idea when it was still light out. Sorry…:persevere:
But it’s one of these:


Maybe finding a way to cut a 4" hole through the well cover and adding something like this.


Not specifically this necessarily but you get the idea.


Is it screwed to the wall?

I’m thinking you could prop it up with a 6 inch extension on the bottom, put your dryer vent there and then run clear plastic (or some plexiglass if you’re going more permanent, I’d even cut the 4 inch hole for the vent in the plexiglass) around the rest of the open area. That way you don’t have to cut a hole in the bubble, and you can still seal around the lower edges with a bit of silicone.

Make it as permanent or temporary as you want. Anyway, just an idea.

You can get this stuff for about $35 from Home Depot:


I think that this is a good answer (raising the bubble) if possible. Poking a hole in the rain bubble will make you rely on sealant only at the penetration (meaning it will most likely leak). Raising the bubble would make it make it so you could undo it if when you move.

If you do have to penetrate the bubble use clear silicon sealant, not caulk. Buy an extra bubble to replace the altered one since a matching one may not be available later.


I’ve been venting into a window well since April using blue foam insulation panels with the usual dryer vent. We have heavy duty lexan covers that clip to the top of the wells, so I just move it when running. Trust me, you do not want to vent into a capped well. :wink:


I think you need some sort of elevated roof vent to go through the well cover. If you live in Arizona, 1/2" might be enough (the one in @rpegg’s post looks to be about 1"). If you live in Seattle, you need 4-6" to cover not just pooling rain water but splashing raindrops.

You also need a perfect fit and you need to seal it all very solidly with silicone . The absolute last thing you want is water getting inside your Glowforge.


I was kind of thinking along those lines; it’s sealing it to the cap that’s the trick. The top isn’t flat so getting a good seal is gonna take some doing.


That’s a really interesting idea. It’s one more right angle to work into it (unless I get creative with angles… hmmmmmm…) but it would certainly solve the issue of cutting through the hood. It is screwed down, but that’s solvable. OK, thats option #3; gonna give that some thought!


Yeah, I was thinking just cutting the 4" hole would be tough enough. But if you get it cut just have to seal around the pipe. Let everything else can float above.


That’s a thought. It would mean running around to pull off the hood when cutting, and would mean I can’t cut while it’s raining, and I would have to remember to put it back, but it’s way way simpler. I like it. That’s option #4.

My overriding issue is that engineering this is keeping me from doing what I really want to do, which is Forging. So Typical of me. Maybe a brut force simple approach is my best bet. Thanks for the input!




:+1: That’s exactly how I ended up with this “solution”-- PRU arrived and I wanted to 'forge right dang now. I keep thinking I need a better solution, but am starting to have embraced “better is the enemy of good enough.”


Alternate venting solutions go in Beyond the Manual, so I’ll move this there - good luck!