In article . com,
bp writes:
Hi,

I live in an old terraced house approx 100 years old. On the ground
floor it has a suspended wooden floor. I have only lived here for 1
year, but since I moved in I noticed that as I walk towards the
chimney breasts (in both groud floor rooms), there was a noticable
incline in the floor, such that at the chimney breast end the floor
appears lower.

I have lifted the carpet, inspected the floor and noticed that some of
the joists either side of the chimney (in the alcoves) had been
replaced but were not supported. They were just in mid air. I guess
that over time the floor just saggged, and thus resulted in the floor
not being level.

I used some quarry tiles and slate pieces to pack the joists near the
alcove to the right height so the floor is level.

This has resulted in one problem. The origianal hearth (built with
the house)now appears sunken as the surrounding floorborads are now
approx 1 inch higher.

Now I do not want to expose the hearth as the end result is to lay
laminate over the entire floor. There is no fire in the chimney and I
dont intend to put one. I have just had it plastered inside and want
to leave it open (ie decorative).

So, how can I bring up the hearth to the level of the rest of the
floor. Two options come to mind

1) Fill with concrete. The hearth at the minute dost look too
appealling anyway. DO I nned to lay down some kind of damp proof
membrane for the concrete

2) floorboards (or any other wood). There is not enough depth to lay
joist (or any other kind of strip) to attach the boards on to). So I
could lay anypeice of wood the fill the gap.

Would either of these solutions be OK

You will probably find there's no damp proof course under the hearth
infill as it was kept dry by frequent warm fires, and latterly by
evaporation from the top. You may have problems if you put laminate
directly over this. In my case, I dug out the hearth to at least a
foot below the floor level, and then layed floorboards and extra
joists as necessary.

You could put a damp proof membrane over it, but this will make it
get more damp as there won't be any drying from the top anymore.
In a house of this age, timber in contact was usually not protected
from a damp hearth (as it wasn't expected to get that damp between
being heated). If you can tuck the membrane between any timber and
the hearth you might be OK, otherwise the timber will rot. Whilst
you are down there, make sure there are plenty of airbricks to the
outside. That will help for keeping nearby timber dry, but won't
help for timber in contact with the hearth.

--
Andrew Gabriel
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