detecting a starting leak... damp sensors?

mymedi

Another thread reminded me of a question I wanted to investigate for a while.

I'm interested in whether there are any damp sensors on the market.
To be clear - not damp meters. Sensors in the sense that you can install them under the bath, or on a pipe, or under the roof valley and wire them into a single panel which would indicate whether it's receiving a signal from the sensor or not. The purpose being to detect slow leaks in places that are impossible to investigate without opening up (behind plaster, under the roof, etc). The sensitivity would have to be quite good - so that it would react to rising levels of damp, not actual water present.

Has anyone heard of anything like that? I'm having difficulty finding it, but perhaps I'm just not searching for the right thing...
Thanks!

Mr_Ted

:rotfl:Would have to be a damned great sensor to cover all those options or where a leak might occur:rotfl:

Rain sensors are available but they are installed in open spaces on roofs and used to shut vents in the event of rain, but rain usually dont just fall in one spot;)

mymedi

Well, I'm not suggesting using one, of course.
If you have a property with potential risk of damp, you could stick a couple dozen of these in various places.
I've seen some which are really basic - two copper strips stuck on carton - when the carton gets wet, the circuit is closed and the signal gets through.
I'm just not sure of the longevity of these and sensitivity to the carton getting damp as opposed to wet...

Mr_Ted

:rotfl:You could if your the CE of a Bank:rotfl:

mymedi

This is what I'm talking about - seems easy enough...

http://www.qub.ac.uk/schools/ClimateChangeandthegreeningofmasonryimplicationsforbuiltheritageandnewbuild/FileStore/Filetoupload,345945,en.pdf

ilikewatch

We have a rudimentary system to sense leaks on the first and second floor of our house - there are thin panels of gypsum sandwiched between paper, fixed to the underside of the floor joists. If there is a leak a dark patch is visible on this "indicator panel" when viewed from the room below. The panels can be painted to fit in with the decor of the room below.