What the heck is this doing under my floor boards?!

[LFS19]

So, I’m fitting some new softwood flooring and found a huge stone slab on a bed of gravle underneath the old boards.

Any ideas why?

To give some background information; 1930s house, room is a bedroom that previously had a shower in the corner that the stone slab is in.
Looks as though they’ve removed an existing joist and placed it the other way along with some supporting timber; presumably to support the weight of the shower base.
I would’ve initially thought the stone was there to support the shower too, though it’s far too small to cover a shower base width ways.

Thanks!

Here are a couple of photos of it (uploader said the files were too large to imbed into the post):

https://imgur.com/a/7o9YhNn

 

[LancsRick]

Pretty sure I saw a horror film that started like this ..

 

[sammy.se]

I have a concrete slab in almost every room of my Victorian house: it's beneath and in front of where the fireplaces used to be.

Could it be the same reason? Did they have fireplaces in the corners of some rooms?

They are very well constructed, no issue for either the floor or ceiling below, both completely level, so I'm not touching them...

Sent from my Nexus 5X using Tapatalk

 

[LFS19]

Well you see, I forgot to mention in my original post but mine isn’t level. It fact, there’s a significant dip in that corner that’s going to need some packing for the new boards.

Maybe they had a fireplace there, who knows.

I’ve uploaded a picture now.

Cheers

Edit: I’m also unsure how far it runs under the wall and into the other room (bathroom) though it may just go slightly under the wall.

 

[LFS19]

I have a concrete slab in almost every room of my Victorian house: it's beneath and in front of where the fireplaces used to be.

Could it be the same reason? Did they have fireplaces in the corners of some rooms?

They are very well constructed, no issue for either the floor or ceiling below, both completely level, so I'm not touching them...

Sent from my Nexus 5X using Tapatalk

Actually sammy, I think you might be on the money with the old fireplace idea.
We had a sulphur leach directly above that area due to an old chimney stack that hadn’t been capped off properly.

Also, looking at the surrounding timber, it looks to me to be as old as the joists.

 

[sammy.se]

It's probably that then... You can probably safely board over it and in another 90 years someone else will discover it

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[MikeG.]

If it isn't a fireplace (which would be favourite), it might just be a step marking an old doorway. Obviously the timber and plasterboard above it dates to later than the house, so taking that off should reveal a bit more about your mystery masonry.

 

[LFS19]

It's probably that then... You can probably safely board over it and in another 90 years someone else will discover it

Sent from my Nexus 5X using Tapatalk

Yep. I love discovering things like this to be honest!

Cheers for comments.

 

[LFS19]

If it isn't a fireplace (which would be favourite), it might just be a step marking an old doorway. Obviously the timber and plasterboard above it dates to later than the house, so taking that off should reveal a bit more about your mystery masonry.

Can’t be an old doorway as that wall leads to the outside. And the plasterboard behind it was me all the walls are old lath and plaster.

Looks like it’s definitly the reminants of an old fireplace. Never seen one in the corner of the rook before, though.

Thanks for the comments

 

[Stanleymonkey]

You're all wrong - it's the first step going DOWN......