My basement was tanked and converted about two years ago by professional
builders.

Since that time I've *seen* no indication of damp. All the white-painted
plaster looks as white as day 1 and there are no obvious indicators (mould,
moisture stains).

However a piece of cardboard left in the room for a few days will get
slightly soft, compared with another piece left elsewhere in the house,
which suggests to me that the air might by moist.

The basement is about 60% below ground level. It is heated via central
heating radiator as required for human comfort, there's a vent in the one
window at one end and an extractor in the adjoining en-suite (separated by
brick wall and not directly adjoining (via small corridor and 2 doors).

I want to move my bedroom in to the space but fear health/clothes damage
consequences caused by damp. How do I measure the atmosphere to confirm if
all's well? I've seen probes that test dampness in wall surfaces, but that
shouldn't be at fault if tanking was successful.

I've thought about renting a dehumidifier to ensure no remaining damp, but I
need a reference before and target after to know if there is a problem now
that requires action and whether its a recurring problem, further down the
line.

Can anyone offer advice?

TIA.

on 10/05/2008, JustMe supposed :
My basement was tanked and converted about two years ago by professional
builders.

Since that time I've *seen* no indication of damp. All the white-painted
plaster looks as white as day 1 and there are no obvious indicators (mould,
moisture stains).

However a piece of cardboard left in the room for a few days will get
slightly soft, compared with another piece left elsewhere in the house,
which suggests to me that the air might by moist.

The basement is about 60% below ground level. It is heated via central
heating radiator as required for human comfort, there's a vent in the one
window at one end and an extractor in the adjoining en-suite (separated by
brick wall and not directly adjoining (via small corridor and 2 doors).

I want to move my bedroom in to the space but fear health/clothes damage
consequences caused by damp. How do I measure the atmosphere to confirm if
all's well? I've seen probes that test dampness in wall surfaces, but that
shouldn't be at fault if tanking was successful.

I've thought about renting a dehumidifier to ensure no remaining damp, but I
need a reference before and target after to know if there is a problem now
that requires action and whether its a recurring problem, further down the
line.

Many of the cheap weather stations include a Relative Humidity gauge
for indoors. Maplin probably sell them.

If the walls seem OK, inadequate ventilation might be the cause. A
dehumidifier would certainly help.

--
Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

JustMe wrote:
My basement was tanked and converted about two years ago by professional
builders.

Since that time I've *seen* no indication of damp. All the white-painted
plaster looks as white as day 1 and there are no obvious indicators (mould,
moisture stains).

However a piece of cardboard left in the room for a few days will get
slightly soft, compared with another piece left elsewhere in the house,
which suggests to me that the air might by moist.

The basement is about 60% below ground level. It is heated via central
heating radiator as required for human comfort, there's a vent in the one
window at one end and an extractor in the adjoining en-suite (separated by
brick wall and not directly adjoining (via small corridor and 2 doors).

I want to move my bedroom in to the space but fear health/clothes damage
consequences caused by damp. How do I measure the atmosphere to confirm if
all's well? I've seen probes that test dampness in wall surfaces, but that
shouldn't be at fault if tanking was successful.

I've thought about renting a dehumidifier to ensure no remaining damp, but I
need a reference before and target after to know if there is a problem now
that requires action and whether its a recurring problem, further down the
line.

Can anyone offer advice?

TIA.



A simple hygrometer will give you the relative humidity figure

http://www.amazon.co.uk/West-Humidit.../dp/B0001P1AY4

but the cardboard is probably telling you all you need to know.

JustMe wrote in message
...
My basement was tanked and converted about two years ago by professional
builders.

Since that time I've *seen* no indication of damp. All the white-painted
plaster looks as white as day 1 and there are no obvious indicators
(mould,
moisture stains).

However a piece of cardboard left in the room for a few days will get
slightly soft, compared with another piece left elsewhere in the house,
which suggests to me that the air might by moist.

The basement is about 60% below ground level. It is heated via central
heating radiator as required for human comfort, there's a vent in the one
window at one end and an extractor in the adjoining en-suite (separated by
brick wall and not directly adjoining (via small corridor and 2 doors).

I want to move my bedroom in to the space but fear health/clothes damage
consequences caused by damp. How do I measure the atmosphere to confirm if
all's well? I've seen probes that test dampness in wall surfaces, but that
shouldn't be at fault if tanking was successful.

I've thought about renting a dehumidifier to ensure no remaining damp, but
I
need a reference before and target after to know if there is a problem
now
that requires action and whether its a recurring problem, further down the
line.

Can anyone offer advice?

TIA.



If you want to make a dampmeter, borrow or buy a digital voltmeter.
Get a couple of pop-rivets (hard steel pins) and grind the ends to points
and squash/clamp the rivet parts in between 2 bits of soft wood, with the
pins about 1 inch apart.

Connect each pin to the voltmeter and set on the resistance scale and push
the rivet pins against the plaster.
Reading on meter scale and corresponding dampness for brick/plaster
10M , 1%
1M , 2%
100K , 38%
10K , 50%

M= megohm , K = kilohm, interpolate for actual reradings

--
General electronic repairs, most things repaired, other than TVs and PCs
http://www.divdev.fsnet.co.uk/repairs.htm

Diverse Devices, Southampton, England

N_Cook wrote:
JustMe wrote in message
...

My basement was tanked and converted about two years ago by professional
builders.

Since that time I've *seen* no indication of damp. All the white-painted
plaster looks as white as day 1 and there are no obvious indicators
(mould,
moisture stains).

However a piece of cardboard left in the room for a few days will get
slightly soft, compared with another piece left elsewhere in the house,
which suggests to me that the air might by moist.

The basement is about 60% below ground level. It is heated via central
heating radiator as required for human comfort, there's a vent in the one
window at one end and an extractor in the adjoining en-suite (separated by
brick wall and not directly adjoining (via small corridor and 2 doors).

I want to move my bedroom in to the space but fear health/clothes damage
consequences caused by damp. How do I measure the atmosphere to confirm if
all's well? I've seen probes that test dampness in wall surfaces, but that
shouldn't be at fault if tanking was successful.

I've thought about renting a dehumidifier to ensure no remaining damp, but
I
need a reference before and target after to know if there is a problem
now
that requires action and whether its a recurring problem, further down the
line.

Can anyone offer advice?

TIA.



If you want to make a dampmeter, borrow or buy a digital voltmeter.
Get a couple of pop-rivets (hard steel pins) and grind the ends to points
and squash/clamp the rivet parts in between 2 bits of soft wood, with the
pins about 1 inch apart.

Connect each pin to the voltmeter and set on the resistance scale and push
the rivet pins against the plaster.
Reading on meter scale and corresponding dampness for brick/plaster
10M , 1%
1M , 2%
100K , 38%
10K , 50%

M= megohm , K = kilohm, interpolate for actual reradings

Just bear in mind damp meters actually measure resistance,
which is not reliably correlated with wall moisture content.


NT

wrote:
N_Cook wrote:
JustMe wrote in message
...

My basement was tanked and converted about two years ago by professional
builders.

Since that time I've *seen* no indication of damp. All the white-painted
plaster looks as white as day 1 and there are no obvious indicators
(mould,
moisture stains).

However a piece of cardboard left in the room for a few days will get
slightly soft, compared with another piece left elsewhere in the house,
which suggests to me that the air might by moist.

The basement is about 60% below ground level. It is heated via central
heating radiator as required for human comfort, there's a vent in the one
window at one end and an extractor in the adjoining en-suite (separated by
brick wall and not directly adjoining (via small corridor and 2 doors).

I want to move my bedroom in to the space but fear health/clothes damage
consequences caused by damp. How do I measure the atmosphere to confirm if
all's well? I've seen probes that test dampness in wall surfaces, but that
shouldn't be at fault if tanking was successful.

I've thought about renting a dehumidifier to ensure no remaining damp, but
I
need a reference before and target after to know if there is a problem
now
that requires action and whether its a recurring problem, further down the
line.

Can anyone offer advice?

TIA.


If you want to make a dampmeter, borrow or buy a digital voltmeter.
Get a couple of pop-rivets (hard steel pins) and grind the ends to points
and squash/clamp the rivet parts in between 2 bits of soft wood, with the
pins about 1 inch apart.

Connect each pin to the voltmeter and set on the resistance scale and push
the rivet pins against the plaster.
Reading on meter scale and corresponding dampness for brick/plaster
10M , 1%
1M , 2%
100K , 38%
10K , 50%

M= megohm , K = kilohm, interpolate for actual reradings

Just bear in mind damp meters actually measure resistance,
which is not reliably correlated with wall moisture content.


NT

Plus it's not what the OP asked for.

wrote in message
...
N_Cook wrote:
JustMe wrote in message
...

My basement was tanked and converted about two years ago by
professional
builders.

Since that time I've *seen* no indication of damp. All the
white-painted
plaster looks as white as day 1 and there are no obvious indicators
(mould,
moisture stains).

However a piece of cardboard left in the room for a few days will get
slightly soft, compared with another piece left elsewhere in the
house,
which suggests to me that the air might by moist.

The basement is about 60% below ground level. It is heated via central
heating radiator as required for human comfort, there's a vent in the
one
window at one end and an extractor in the adjoining en-suite
(separated by
brick wall and not directly adjoining (via small corridor and 2
doors).

I want to move my bedroom in to the space but fear health/clothes
damage
consequences caused by damp. How do I measure the atmosphere to
confirm if
all's well? I've seen probes that test dampness in wall surfaces, but
that
shouldn't be at fault if tanking was successful.

I've thought about renting a dehumidifier to ensure no remaining damp,
but
I
need a reference before and target after to know if there is a
problem
now
that requires action and whether its a recurring problem, further down
the
line.

Can anyone offer advice?

TIA.



If you want to make a dampmeter, borrow or buy a digital voltmeter.
Get a couple of pop-rivets (hard steel pins) and grind the ends to
points
and squash/clamp the rivet parts in between 2 bits of soft wood, with
the
pins about 1 inch apart.

Connect each pin to the voltmeter and set on the resistance scale and
push
the rivet pins against the plaster.
Reading on meter scale and corresponding dampness for brick/plaster
10M , 1%
1M , 2%
100K , 38%
10K , 50%

M= megohm , K = kilohm, interpolate for actual reradings

Just bear in mind damp meters actually measure resistance,
which is not reliably correlated with wall moisture content.


NT

Very true. I knew of someone with a house with interior walls constructed of
breeze-block with some conductive material in the composition.
Someone fitting an over-picture lamp managed to put a mounting screw through
the mains cable - lamp worked perfectly ok. The other side of the wall was
the bathroom and someone placed their hand on the wall while in the bath

The OP knows there is damp in the air from the cardboard test
So pointless monitoring the air humidity, more a matter of tracing where the
"tanking" is flawed/breached.

--
General electronic repairs, most things repaired, other than TVs and PCs
http://www.divdev.fsnet.co.uk/repairs.htm

Diverse Devices, Southampton, England

The OP knows there is damp in the air from the cardboard test
So pointless monitoring the air humidity, more a matter of tracing where the
"tanking" is flawed/breached.

It may not be flawed/breached. There may just be insufficient
heat/ventilation. The OP mentioned "radiator" in the singular, which may
not be enough.