I was drilling holes on the side of the window to install new venetian blinds. I found that the drill bit was not going through. Upon taking a closer look I found metal. Why is there metal on the sides of the window rather than top and bottom? Is it safe to drill through this?
A properly exposed photo would be great. I can't see much there. The short answer is that you've either hit structural or mechanical parts. I wouldn't mount to either of those without approval from the manufacturer.– isherwoodAug 30, 2022 at 12:42
What are your walls made of? In the UK, I believe masonry is far more common than here in the US. If it's masonry, there may be a steel lintel above the window that hold up the brick/concrete that goes across the top of the window, and that may be what you've hit.– FreeManAug 30, 2022 at 12:43
2drywall corner bead– Fresh CodemongerAug 30, 2022 at 19:12
The walls are masonry, no dry walls. I expect that there to be lintel above and below the window. However this metal is on the sides of the window.– quantum231Aug 30, 2022 at 22:22
Agree with @FreshCodemonger, probably the back edge of the drywall bead. Drill the inner side hole and I bet it's masonry. And to answer the question, you can drill through it, but be careful the drill bit doesn't snag as it's very close to the face of the wall and could spall some plasterwork.– handymanAug 31, 2022 at 7:14
Since we can only guess, I will: If it were a double hung sash window that would be the casing for the counterweights or springs. But it isn't. Maybe it once was? Maybe it's just metal framing for the window, like metal 2x4 studs because that's what the builder had on hand. We can't be sure.
If you are unsure what's behind the metal where you've indicated, you could avoid the question by mounting the blinds in the framing or masonry above the window, where I've shown with green squares.
Some blinds can only be mounted by the sides but many can be mounted by brackets clipped anywhere along the top. You would need to get a blind like that, and a few inches longer.
I finally got a blind that is cheaper and not as good but it clips on the top anywhere except a couple of places where the rotating mechanism exists inside the blind. Aug 30, 2022 at 22:24