Is the lintel missing above the terrace door here?

Is it safe if the stones are just bricked in like that?

Yes! Almost every brick-faced house is like that. It holds because of the mortar. The house is not made of clinker alone, that is just a facing shell. More photos won't change that. Go for a walk and take a look at other houses.

Exactly. Bricks are used as clinker bricks. Is it really safe if the bricks are just simply mortared in?

It has been safe for a hundred years. Nothing falls down.

Hello,

I now have the information that a masonry lintel may only be built up to a length of 1.26 m without additional reinforcement. The terrace door has a width of about 1.70. So reinforcement would have had to be installed. However, I cannot see it. What is your opinion.

Thomas

I now have the information that a masonry lintel may only be built up to a length of 1.26 m without additional reinforcement. The patio door is about 1.70 m wide. So a reinforcement would have had to be installed. But I cannot see it. What is your opinion?

The house is already older. Everything is fine and everything will remain fine - just like in other houses. Apart from that: Where does the opinion come from? How is the lintel actually made in craftsmanship? - without any measures? - with joint reinforcement? - suspended precast lintel? - support brackets? As long as you have no concrete plans, you will never find out how it was built without opening the component. In the end, however, it doesn't matter. What is your problem? Have you also checked whether the window was installed correctly at all and how the seals were executed? I find that much more interesting based on the photo.