Is this rubble in my victorian floor?

[lifeofchris]

I am in the process of refurbishing a victorian house, I have checked in 3 places across the house, there is about 150mm of rubble with a black almost volcanic (or coal??) and concrete-like consistency, it is almost light weight. This is the most obvious one in front of the fireplace.

In the staircase it is more rubble-like but whoever put it in went through the effort of battening and planking out between the floor joists to create a false pocket to fill the void.

Does anybody know what this is?

Apologies for the rotation!

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[lifeofchris]

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[JohnD]

in front of the fireplaces it is a non-structural hearth of lightweight concrete, which probably used to be tiled, to reduce the risk of the house burning down when hot coals fall out of the fireplace.

Under the stairs it will be an attempt to reduce noise.

You could use dense mineral wool batts under the floor to reduce airbourne noise transmission, also carpet and underfelt on the stairs. Victorian houses will not have had fitted carpets or thick carpeting, or rubber-soled shoes, so were noisy.

 

[lifeofchris]

Ok hmm.. I will have to remove it all to get my interstitial insulation and underfloor heating pipes in!

 

[bobby spray]

it's there to reduce noise.... remove it at your peril.

 

[lifeofchris]

I will be putting back the same and more. I dont believe in this day and age anyone would specify "rubble" for any kind of insulation!