Cracks Around Door Frame new and increasing - subsidence?

[thepablo]

I own a house built in 1900 and recently I have noticed cracks appearing around the door frame on the first floor.

There are 2 doors with cracks.
They are angled about 45 degrees and only on one side of the frame.
The doors are on opposite sides of building and cracks are the side which is more central to the house in each case. So crack on right side for one and left side for other (photos attached)

They have not had new plasterig etc in recent years.

Does this suggest that there is a beam sagging in the middle of the house? causing the frame to both dip?
Or is it general subsidence?
Or is it just something i need to cover up!

The property does already have a slight angle to it and the frame is already sloping towards the cracks, however that is old movement.

I am a bit concerned about what actions to take!

 

[Harbourwoodwork]

Post lots of pics of the wall and under the floor

 

[^woody^]

The cause could be one or a combination of several things, but subsidence would not be anywhere near the top of the list

 

[thepablo]

View media item 54172
View media item 54173
2 photos of the bedroom frame - from both sides of the door.

I'll get a photo of the other door if I can

this is all new cracking in last week or so I think

 

[Harbourwoodwork]

More bigger pic's would be useful
what building work has been done in the last few years?
what floor are the doors on?(ground 1st etc..)
what are the walls made of (stud or brick)?
Pic's of structure under floor if possible

 

[thepablo]

It's a mid terraced London house. In May this year I built a side return to the kitchen. It involved new steels at the back of the house. Structural work was completed in August.

The loft has been converted into a bedroom bathroom, but this was done in 1980s.

My bedroom is question is the front of the house.

I do have a structural engineer coming tomorrow.....

 

[thepablo]

View media item 54198
This is main beam from below the door frames in sitting room, in perfect condition.

 

[^woody^]

What did the engineer say?

 

[thepablo]

He told me to stop worrying!
General settlement, nothing to concern me, am getting the room redecorated in the next few months anyway.