Ventilation hole concrete wall 70s house

[simon3d]

Hello!

We have a two-story 1970s house with concrete/stone on the bottom and then a wooden upper floor. We started drilling a ventilation hole on the ground floor from the outside and encountered several reinforcing bars halfway through. Tried with a hole saw, various drills, etc., but can't get through the rebar. What can be used to get through the reinforcement? It's a bit unsettling when it sparks and you can see the wall insulation from the side.. can you even cut the rebar without weakening the house too much?

Really grateful for all the answers! PS will attach a picture soon.

 

[simon3d]

This is what it looks like

 

[topmount]

Where on the wall do you drill? When beam above the window?

 

[simon3d]

Where on the wall are you drilling? When beam over the window?

Diagonally over the window, it's close to the wooden facade...

 

[elmont]

With a diamond hole saw/core drill, available for rent or purchase.