Rubble under floorboards?

busterjones

Hi. Live in very old house 1840s. Has latte and plaster ceilings. But when I lifted floorboards recently to add insulation there is lots of rubble sitting on top of the ceiling underneath.

I can see in a few places that this was once a suspended suspended layer between the joists and immediately under the boards. There are lattes in these sections and in other places can see just lattes remaining.

Was this common practice? Anyone seen this before?

Hoping it's old plaster and not asbestos!!!!!!

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busterjones

More pics

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blackbox

The house probably pre-dates the use of asbestos, but you would be wise to get it tested.

busterjones

Have done a bit of searching and could this be gypsum plaster?

10-10-20

Looks like it might be lime plaster with horse hair, or whatever the local farm animals in the area at the time were, mixed in for strength.

dathi

its a lime based plaster it was used directly under the floor boards to stop draughts coming up through the floor boards quite common in old houses

Kaybaykwah

https://www.boards.ie/discussion/comment/123480201#Comment_123480201

Yes, the same way lime was used for dabbing houses and barns as a protective cover. It was also good at keeping bugs away from human and animal habitation.

Odelay

Completely normal. Expect to find some mouse and rat skeletons too!