"robgraham" wrote in message
...
On May 23, 3:48 pm, RobertL wrote:
On Sunday, December 9, 2012 2:42:18 PM UTC, Geoff Pearson wrote:
I am thinking of improving the floor insulation of my house. Under the
ground floor of my 1897 stone-built house in Edinburgh I have a space
about
1.6m high under all the rooms so access for work is very good. My
energy
bills (gas+electricity) are about £2800 a year.

The floor is a standard Edinburgh floor: 11 inch joists with the space
between filled with ash and covered in plaster, supported on riven
wooden
strips, themselves supported on battens along the joists. This
deafening

Forgive me for repeating this story if you read it before.

The architect Hope Bagnell once described the sound insulation of Glasgow
tenements (with sand/ash filling between joists) and compared it to that
in (1960s) buildings. He said "in Victorian times it was boasted that
you could not hear a baby being born in the room above. These days you
can hear it being conceived".

Robert

I missed this post so couldn't put in my pennyworth at the time. I'm
the poor peasant that lives in a farm cottage 10 miles outside
Edinburgh and have a similar problem without the access the OP has.

If I had spotted the post back in December, I would have recommended
that the OP invests in one of the inexpensive IR thermometers off Ebay
or the likes to see quite what the floor temperature was. It might
well have been that it was only a degree or so less than the wall
temperature and therefore further insulation was unnecessary. That
opportunity has now been missed unfortunately as my suspicion is that
the deadening would act as quite adequate insulation.

I measure 3 or 4C in my situation in comparison to the wall surface
temperature - plasterboard over insulation and 3ft thick stone
walls.

My approach is going to have to be to reduce the excessive under floor
ventilation, but I am going to put in sensors to monitor the
temperature and humidity in the timbers.

Rob

One of the factors that drove me this way is that the house is significantly
colder in high winds - so there is air leakage somewhere and we have sanded
floor boards on the ground floor. Windows and doors are well
draught-stripped and there is no discernible air flow around any of them.
Fitted carpet might have been one solution but it looks wrong in these
houses. The void below is very dry as there is very good through
ventilation - the void area floor is garden level at the back. But if the
under floor insulation doesn't help it is hard to see what might and it was
free (70 sq metres - I've not priced that).

I am very familiar with Edinburgh floors, having had two Georgian flats in
the New Town before this modern, 1897, house. The deafening (not deadening)
is intended mainly for sound insulation by solid mass. It has an air gap on
top of the ash and plaster which is ventilated and the air moves well
through that. In the Georgian flats there would have been little need for
heat insulation - owners were wealthy, coal was cheap and when we did light
coal or log fires the heat was astonishing. The sound insulation effect was
very good - not possible to hear people in flats above or below.

Likewise in this house - the servants' quarters are quite large: bedroom,
parlour, scullery, pantry and lavatory all separate from the rest of the
house: heating costs irrelevant - we had 7 fireplaces. Now the house is
occupied by poverty-stricken pensioners, life is different. I do plan to
buy one of those IR thermometers.