Cold spots on wall ?

[Johnhjonny5]

Hi all I,m new on hear I've got. A question I need some advice on please . I'm a joiner by trade and have a good understanding of the building game . What it is on a gable wall in my living room I have recently noticed what looks to be the dab marks from the plaster board showing through the top foot of my wall all the way along . The room is a decent size and they are all about the same height so guessing dab . Now panic set in and I instantly thought damp ingress from the cavity wall some how finding its way through the dabs. The wall is painted in Maggie . , when I shine a torch directly at the wall they aren't visable . And they don't seem to be showing any tell tale water marks . However the wall is cold to the touch . Is it feasible that with the weather getting colder these marks are cold spots ? Ps wall does fell quite cooL. The wall is a cavity wall and would be surprised if water had bridge it the length of the entire room . The house is around 25/ evo years old and be live it had the blown in insulation .

 

[KenGMac]

Johnhjonny5, good evening, and Welcome to the board, This being your first post in here!

OK so you have a 25 year old property, was it originally a Council Built / Let property?

You note that the Cavity may have Blown Fiber Cavity Wall insulation?

If the Insulation was installed by the Council and the Installation was some time ago say 10+ Years ago then there is a very high possibility that your property is suffering from bridging of the cavity caused by saturated blown insulation in the cavity, BUT???

We have had an extremely dry November, nationwide?

As for the use of the torch? My preferred option for using a torch is NOT to direct the beam directly at the wall, hold the torch Parallel to the wall and scan the beam up and down, the brighter the beam washing over the wall the more defects are located, I have a 1,000 Lumen Led-Lenzer it works well.

As for other potential causation's? is the affected room on a ground floor? if so??? the DPC may be failing, BUT? this scenario "generally" occurs in patches and in spots?

Ken

 

[Johnhjonny5]

Hi Ken thanks for your fast reply the house is a leach home which was a national house builder which was baught out by persimmon homes. Yes sorry the wall is on the ground floor . I'll try looking down the wall like you have suggested and c what this yields . The spots are a foot down from the ceiling hight would this rule out the dpc Theory ?

 

[Newboy]

More than likely that you're seeing condensation on the cold spots (relative to the rest of the wall) formed by the adhesive.

Try increasing ventilation and temperature in the affected room