Dear group,

It is my intention to replace my upstairs floors with chipboard, enabling me
to re-use the boards downstairs for a sanded floor. As I will be improving
the ventilation under the ground floor, I hope to staple netting between the
joists and insulate with 50mm of mineral wool.

I Googled for info on sealing draughts in non-tongue_and_groove and mostly
found the usual papier mache and solid wood fillets solutions.

I'm wondering if breathable roofing membrane directly under the boards might
be a better solution
(or maybe used in place of netting to suspend the mineral wool ?)

Jeremy

"brugnospamsia" wrote in message
. uk...
Dear group,

It is my intention to replace my upstairs floors with chipboard, enabling
me
to re-use the boards downstairs for a sanded floor. As I will be improving
the ventilation under the ground floor, I hope to staple netting between
the
joists and insulate with 50mm of mineral wool.

I Googled for info on sealing draughts in non-tongue_and_groove and mostly
found the usual papier mache and solid wood fillets solutions.

I'm wondering if breathable roofing membrane directly under the boards
might
be a better solution
(or maybe used in place of netting to suspend the mineral wool ?)

I've used the foil covered Airtec stuff Screwfix sell as it forms a
condensation barrier as well. Also I used Kingspan instead of mineral wool
(second quality is fine in this application) rammed between the floorboards
as it insulates better.

"Mike" wrote in message
...

"brugnospamsia" wrote in message
. uk...
Dear group,

It is my intention to replace my upstairs floors with chipboard,
enabling
me
to re-use the boards downstairs for a sanded floor. As I will be
improving
the ventilation under the ground floor, I hope to staple netting between
the
joists and insulate with 50mm of mineral wool.

I Googled for info on sealing draughts in non-tongue_and_groove and
mostly
found the usual papier mache and solid wood fillets solutions.

I'm wondering if breathable roofing membrane directly under the boards
might
be a better solution
(or maybe used in place of netting to suspend the mineral wool ?)

I've used the foil covered Airtec stuff Screwfix sell as it forms a
condensation barrier as well. Also I used Kingspan instead of mineral
wool
(second quality is fine in this application) rammed between the
floorboards
as it insulates better.


Sorry to be dense, but is this what you mean ?

http://uk.geocities.com/gentlegreengiant/floor.JPG

(24KBytes)

thanks ...

Jeremy

"Mike" wrote in message
...

I Googled for info on sealing draughts in non-tongue_and_groove and
mostly
found the usual papier mache and solid wood fillets solutions.

I'm wondering if breathable roofing membrane directly under the boards
might
be a better solution

Yes, but to a diffrent problem. The papier mache and solid wood
fillets solutions provide some insulation but primarily are there to
stop things falling down the gap

Anna
~~ Anna Kettle, Suffolk, England
|""""| ~ Lime plaster repairs
/ ^^ \ // Freehand modelling in lime: overmantels, pargeting etc
|____| www.kettlenet.co.uk 01359 230642

"Anna Kettle" wrote in message
...
"Mike" wrote in message
...

I Googled for info on sealing draughts in non-tongue_and_groove and
mostly
found the usual papier mache and solid wood fillets solutions.

I'm wondering if breathable roofing membrane directly under the
boards
might
be a better solution

Yes, but to a diffrent problem. The papier mache and solid wood
fillets solutions provide some insulation but primarily are there to
stop things falling down the gap


I have to say that since I'm planning to leave gaps between the boards
(though maybe not quite of "Brighton Pier" dimensions), I'm starting to
wonder just how long it'll take for the void to fill up on top of my
insulation - though my intention is to improve my lifestyle to the point of
housework ;-)

I suppose I might need to get a discriminating metal detector if people
start dropping valuables on my floor ;-)

"brugnospamsia" wrote in message
. uk...
Dear group,

It is my intention to replace my upstairs floors with chipboard,
enabling
me
to re-use the boards downstairs for a sanded floor. As I will be
improving
the ventilation under the ground floor, I hope to staple netting
between
the
joists and insulate with 50mm of mineral wool.

I Googled for info on sealing draughts in non-tongue_and_groove and
mostly
found the usual papier mache and solid wood fillets solutions.

I'm wondering if breathable roofing membrane directly under the boards
might
be a better solution
(or maybe used in place of netting to suspend the mineral wool ?)

I've used the foil covered Airtec stuff Screwfix sell as it forms a
condensation barrier as well. Also I used Kingspan instead of mineral
wool
(second quality is fine in this application) rammed between the
floorboards
as it insulates better.


Sorry to be dense, but is this what you mean ?

http://uk.geocities.com/gentlegreengiant/floor.JPG


Not quite. I thought you said you had the floor up and so I would run the
Airtec over the top of the Kingspan and over the top of the joists so that
before you lay the floor all you can see is Airtec.

If the floor has been fitted then you could instead run the Airtec under the
bottom of the joists as well as under or on top of the Kingspan. The
problem with this method is moisture could be retained against the joists so
you need to build in some slack so that any condensation drains away from
the joists, not towards them.

Either way gives you want one continuous run across all the joists, then
taped up in parallel to give a complete impervious sheet.

"Mike" wrote in message
...

"brugnospamsia" wrote in message
. uk...
Dear group,

It is my intention to replace my upstairs floors with chipboard,
enabling
me
to re-use the boards downstairs for a sanded floor. As I will be
improving
the ventilation under the ground floor, I hope to staple netting
between
the
joists and insulate with 50mm of mineral wool.

I Googled for info on sealing draughts in non-tongue_and_groove and
mostly
found the usual papier mache and solid wood fillets solutions.

I'm wondering if breathable roofing membrane directly under the
boards
might
be a better solution
(or maybe used in place of netting to suspend the mineral wool ?)

I've used the foil covered Airtec stuff Screwfix sell as it forms a
condensation barrier as well. Also I used Kingspan instead of mineral
wool
(second quality is fine in this application) rammed between the
floorboards
as it insulates better.


Sorry to be dense, but is this what you mean ?

http://uk.geocities.com/gentlegreengiant/floor.JPG


Not quite. I thought you said you had the floor up and so I would run the
Airtec over the top of the Kingspan and over the top of the joists so that
before you lay the floor all you can see is Airtec.

If the floor has been fitted then you could instead run the Airtec under
the
bottom of the joists as well as under or on top of the Kingspan. The
problem with this method is moisture could be retained against the joists
so
you need to build in some slack so that any condensation drains away from
the joists, not towards them.

Either way gives you want one continuous run across all the joists, then
taped up in parallel to give a complete impervious sheet.

yes, the floor will be up, I just had the feeling I ought to leave the
joists room to breathe - so a porous membrane with bulky lagging felt
right - also less thickness of material under the boards ...

Having just done a couple of ceilings with dry-lining screws, and having a
nice new drill/driver to play with I'm wondering if there's a nice way to
use japanned screws for floorboards ... no doubt I would have to
countersink, plug the holes with dowel and chisel them flush as I would if I
was making a boat ... shipshape and Bristol fashion .... ?

"brugnospamsia" wrote in message
. uk...

Not quite. I thought you said you had the floor up and so I would run
the
Airtec over the top of the Kingspan and over the top of the joists so
that
before you lay the floor all you can see is Airtec.

If the floor has been fitted then you could instead run the Airtec under
the
bottom of the joists as well as under or on top of the Kingspan. The
problem with this method is moisture could be retained against the
joists
so
you need to build in some slack so that any condensation drains away
from
the joists, not towards them.

Either way gives you want one continuous run across all the joists, then
taped up in parallel to give a complete impervious sheet.

yes, the floor will be up, I just had the feeling I ought to leave the
joists room to breathe - so a porous membrane with bulky lagging felt
right - also less thickness of material under the boards ...

They breathe in the area under the floor - which is what they were designed
to do of course.
The Airtec will squash almost flat between floor and joists.


Having just done a couple of ceilings with dry-lining screws, and having a
nice new drill/driver to play with I'm wondering if there's a nice way to
use japanned screws for floorboards ... no doubt I would have to
countersink, plug the holes with dowel and chisel them flush as I would if
I
was making a boat ... shipshape and Bristol fashion .... ?

If they are nice floorboards you want to have on show then use blind nails.
These are nailed through the tongue such that the groove of the next one can
still fit home tightly. You'll also need tho hire the special tool to
compress them together properly.