Unidentified Material Under Dining Room Carpet

[THills]

Hello, I recently moved into a Victorian terraced house and various parts of the property need some improvement. The carpet in the dining room was damp in one area and has been removed to reveal a sort of concrete material as shown in the first photo.

I was expecting there to be floorboards but they appear to have been covered at some point! Some wood(?) is exposed at the doorway between the living room and the dining room, as can be seen in the second photo, and I assume this has been covered by concrete/screed throughout the dining room before carpet was laid on top.

Could anyone provide some insight into what has been done to this floor and how I could replace the carpet? I've never owned a period house before and would really appreciate any advice!

 

[Cubist]

The last photo suggests a boundary between a suspended wooden floor in one room and a concrete floor in the neighbouring room. If you stamp gently on the concrete floor in various locations does it sound hollow? If so that may indicate a mortar screed has been laid over the original floor boards for some reason If, when you stamp on the floor, you hear no or very little sound, then its a concrete floor of some kind. You could confirm one way or the other by lifting one of the wooden floor boards near the boundary.

 

[THills]

The last photo suggests a boundary between a suspended wooden floor in one room and a concrete floor in the neighbouring room. If you stamp gently on the concrete floor in various locations does it sound hollow? If so that may indicate a mortar screed has been laid over the original floor boards for some reason If, when you stamp on the floor, you hear no or very little sound, then its a concrete floor of some kind. You could confirm one way or the other by lifting one of the wooden floor boards near the boundary.

Thanks for your reply, I think your assessment is probably correct. There's a cellar under the living room floor but I don't get the impression that it ever continued into the living room. The living room would've been the kitchen before a small extension was built so I have wondered whether there could have been flagstones. Do you have any idea what the white pattern is in the first photo?

 

[Cubist]

I'm fairly certain the shape/pattern of the stains are what are made by carpet underlay and the white material/stain is most likely salt that has migrated to the surface of the floor carried by moisture rising through the concrete from the ground below OR pulled from the surface of concrete by water spills indoors. It's a very common phenomenon and nothing to be hugely worried about. Use a stiff brush and a vac to remove the stains in the first instance and keep an eye on it for a few weeks while leaving the floor uncovered if you can.

 

[THills]

I'm fairly certain the shape/pattern of the stains are what are made by carpet underlay and the white material/stain is most likely salt that has migrated to the surface of the floor carried by moisture rising through the concrete from the ground below OR pulled from the surface of concrete by water spills indoors. It's a very common phenomenon and nothing to be hugely worried about. Use a stiff brush and a vac to remove the stains in the first instance and keep an eye on it for a few weeks while leaving the floor uncovered if you can.

Thanks for your advice, I've not really seen the carpet underlay properly but did wonder whether it might have created the pattern. What do you think I could use to replace the carpet? It's not in great condition and isn't really a very practical option for a dining room.

 

[Gothichome]

The cementious material is probably leveling compound. It a very watery cement self leveling compound that gets poured onto the floor. Usually used for laying modern laminate or vinyl floors, or tiling. First time I’ve seen it used for carpeting.