Or to put it another way, the wall is not mouldy now you are no longer hanging wet washing against it and making it damp.
Sick of Mould behind radiator
- Thread starter Mr Sparkle
- Start date
Or to put it another way, the wall is not mouldy now you are no longer hanging wet washing against it and making it damp.
Nobody ever complains loudly, that their CWI works brilliantly, people only complain when it goes wrong. I had it installed in the mid 90's, it works, and no problems. It certainly helps keep the expensive warmth, where it belongs, in the house, and the cold out - things is, you need to do your part, in not generating excess moisture in inside the home.
Mine is fine. I live in a coastal area subject to winter storms and driving rain, exposed on the West. I get no damp. The heating costs dropped noticeably, and my old (15kW boiler) was no longer incapable of keeping the house warm on frosty nights. (Calculated whole-house heat loss at 20C difference dropped to 12kW)
Mine is a modern house with good quality brickwork.
My neighbours have the same result.
Mine is a modern house with good quality brickwork.
My neighbours have the same result.
-Get yourself a towel rail that hangs off the front of the radiator
-Put the towel on it NOT over the radiator
-If you can, leave the radiator on for a bit when the towel goes on
-Open the window for half an hour each morning
-Put the towel on it NOT over the radiator
-If you can, leave the radiator on for a bit when the towel goes on
-Open the window for half an hour each morning
For many years we were nominated contractors to a large housing association.
Terrace housing full refurbishment back to floor joints & roof timbers.
All radiators were installed on outside walls and behind every radiator a 9x6 air brick .Where the tenants couldn't get at them!
Terrace housing full refurbishment back to floor joints & roof timbers.
All radiators were installed on outside walls and behind every radiator a 9x6 air brick .Where the tenants couldn't get at them!
With a reasonable level of warmth in the building, proper insulation, a reasonable level of ventilation in the correct locations, and the generation of moisture properly controlled - internal damp, and mould, is never a problem.
At a guess, as others have suggested, there may have been wet towels etc stuffed part of the way down the back of the rad. That would have prevented the convection currents rising up past the back of the rad.
Now that you have removed the rad, I would not expect the problem to come back (assuming that you are not going to obstruct the airflow).
Wash it down with fungicidal solution or bleach and just paint over it.
No slight intended, but parts of this thread became a tad confusing, in part because of some of your replies. I have been there before, I failed to explain things clearly and assumed that others would know what I meant. Please accept that as constructive criticism.
Best of luck.
Thank you for finally explaining that.
Edit: one further clarification needed: when the rad was fitted on the wall and the mould was appearing, was the radiator actually turned on?
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I think there must be some bit of YouTube algorithm or similar social distraction that is amplifying a story about cavity insulation being useless.
The reality is that it has been used for ~50 years or so with most properties being absolutely fine. I’ve lived in several such houses.
Sure there are walls where it would be problematic, i.e. if the outer skin is leaking and the wall is facing the prevailing wind in an exposed location. But we should (collectively) know where it is OK to use and where it should be avoided. Tell us more about your situation and someone will advise.
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Originally cavity walls were designed to isolate the joist ends from the wetter outside wall so they didn't rot off - i.e. nothing to do with insulation.
Then, in the era of lime mortar and plaster, and breathable materials, cavity walls were designed with airbricks in to the cavity so that any condensation appearing on the inside of the outer leaf and/or any penetration caused by the breathability was evaporated away. Drip points on ties, cavity trays etc controlling any liquid condensation and keeping it away from the inner surface.
Latterly we don't build breathable walls - airtight construction, insulated cavities, tight exterior brickwork with waterproof cement based mortar, still with weep vents, cavity trays etc in case any condensation does appear.
IMHO no2 is the risk - if you have a ventilated cavity designed to work with breathable walls, then filling with CWI and stopping that ventilation is a risk. Perhaps it should just be - "no airbricks to the cavity, CWI is fine, but where airbricks are present treat with caution."
Problems can arise if you have a defective outer leaf to the wall, that lets water in, or if you have a cavity where careless builders allowed mortar, sand and rubble to accumulate inside the cavity during build.
In both cases these defects ought to be rectified, whether or not you have CWI.
I found it very hard to clear out a cavity by raking and vacuuming, but the problem is now so well known that CWI installers check for it before agreeing to do the work.
I expect there are better techniques now.
In both cases these defects ought to be rectified, whether or not you have CWI.
I found it very hard to clear out a cavity by raking and vacuuming, but the problem is now so well known that CWI installers check for it before agreeing to do the work.
I expect there are better techniques now.
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