ᐅ Building layout line / wall line mark

Hello everyone

I have a problem with my basement stairs. The stairs are located outdoors.
I wanted to paint the walls of the stairwell, but now the following issue has come up:
the plaster on the wall was crumbling, so I removed it and discovered a crack running about 1.5 meters (5 feet) along the masonry.
Behind the wall is soil, which is starting to become slightly visible.

Now my question:

How can I seal or repair this crack in the masonry?

So far, I have come up with three ideas:

- simply fill the crack again with mortar or a similar material
- seal it with silicone and then plaster over it again
- seal the crack with bitumen.

What do you think about these options, or do you have any other suggestions?

Hello schnablman,

Could you please take some photos of the wall, its immediate surroundings, and if possible, close-up shots of the crack itself, and upload them here? This might help determine the cause of the cracking.
Additional questions:
What material (which type of stone) is the wall made of?
Is it waterproofed against moisture from the ground, and how is the top covering designed?

Kind regards
Danton

Engineering and Planning Office
Dipl.-Ing. Thomas Brandenburg
Consulting Engineer and Construction Expert
Insurance Specialist (Building Contract)

The wall was cast from regular concrete at the time.

I already know the cause of the issue.
The crack is not really big, at most about 1 cm (0.4 inches) at its widest point, and I would say the depth is around half a centimeter (0.2 inches) at most.

But as I said, it extends over an area.

The soil only becomes visible after it has rained; a little bit is washed out.

Hello schnablman,

unfortunately, I don’t quite understand this.

1. Was the wall originally built from masonry (your first post) or concrete (your second post)?
2. If the crack is only 0.5cm (0.2 inches) deep, how can the soil behind it be visible?

Could this be spalling due to insufficient concrete cover over the reinforcement?

Regards, Danton

Hello everyone!!

Based on what you described, I would first say that you should not underestimate this. A crack 1cm (0.4 inches) wide, in my opinion, already represents a serious defect.
This doesn’t necessarily mean the house might collapse or anything like that, but you should be cautious about it. The cause could be insufficient reinforcement, movement of the masonry, and so on.

My advice to you would be:
I would cut into the crack every 10cm (4 inches) with a cutting disc, then insert stainless steel pins and anchor them. Regarding anchoring, there is a two-component epoxy resin putty that you can pour in.
After that, fill it with exterior adhesive filler and embed mesh strips.

Hopefully, this helps.

Best regards 😉