Cracks In Walls

[novaf4]

My Victorian flat has developed cracks where walls meets walls. I think it's caused by vibrations from the flat upstairs' washing machine. Photos attached.

I've cut out a section at one spot with a stanley knife. It's hard to tell how deep the crack goes. I can see old paint, old lining paper and plaster but I haven't dared open up so much that I can see any brick. I'd like to make this a quick, easy fix that will hopefully last at least 5 years. What I don't want is a complete wall smashing dust fest.

My research shows that Toupret Fibacryl Flexible Crack is worth using. But should I only use that or in conjuction with something else?

Any tips and advice would be much appreciated.

 

[KenGMac]

novaf4, good evening.

From the images posted, it would appear that the room has been split at some time historically, it would be unusual to have a cornice "disappear" as your image shows, normally a cornice is all the way around a "room"

If you tap the two walls in the images does one sound "Solid" and the other sound "Hollow"???

Ken.

 

[opps]

It does look as though the wall where the cornice disappears is not original.

I would be surprised if the washing machine upstairs is the root cause, but it is a possibility.

I often recommend Fibracryl but be aware that it shrinks back quite a lot. Let it shrink and then use a filler of your choice over the top. Sand flat and then "prime". You can then caulk over that.

If it were just a clean and persistent hairline crack I would have recommended a MS polymer such as CT1, they are as flexible as silicone but can be painted over.