A nice little 3 bed terrace in Southsea, bought in 2011 and fully refurbished from solar panels at the top all the way down to new flooring and joists downstairs due to long term penetrating damp (broken gutters and rain running down the outer walls, so no surprise). Anyway, since the new kitchen, bathroom, carpets and full redecoration it has always been a cosy, warm, dry house much loved by the tenants who live there (the new boiler and central heating upgrades probably helped).
So, it was with some distress I noticed patches of mould when I inspected the property in November – a couple of obvious cold spots at the rear (north facing) upstairs, obviously where the loft insulation does not extend all the way to the cavity and the outside walls never really warm up, plus additional patches on the lower portions of windows, presumably where the condensation never properly dries out. In addition to these patches there was extensive surface mould on the wall below the bay window in the downstairs front room (used as a bedroom by the current tenants) which surprised me as it is a south facing window and often the warmest room in the house.
All of the mould was black, surface mould and caused by condensation as opposed to the brown stuff that comes through from damp within the walls. Normal next step is to read the tenants the riot act, tell them to ventilate better, not to dry washing indoors, put lids on saucepans, etc but even when that works, it only works until you change tenants and then you are back to square one. Additionally, since I have made all of my properties ‘fully inclusive’ problems of damp and mould have gone away, presumably because they are now nice warm houses and the dewpoint where moisture in the air condenses on the coldest surfaces and over time becomes mould, had been a thing of the past – so to have so much evidence of mould in such a nice warm house, the moisture levels must have been very high or the cold spots, extremely cold.
So this time, I called in Damp Man.
OK, he probably does not like to be called Damp Man but when you hear of his array of ‘super power’ solutions, you will see why I gave him the name. He came and looked at the house, went away, wrote me a detailed survey report with a bunch of recommendations some of which I was not sure about, so via email over the next few days we looked at alternatives and he explained his logic and suggestions in various areas and then I went to Gosport (I’d call it Fareham but it is probably on the border) and he showed me everything that had been recommended along with demonstrations of a range of products and I bought everything I needed, loaded it all into the van and headed back to book my electrician to get everything installed.
So who is he? None other than Chris Reynolds of Alliance Remedial Supplies who has been to a number of our meetings and given us some very interesting presentations on his area of expertise.
And what did I buy? Let me show you… First thing to do was to get rid of the mould and make good the decoration. Chris sold me a biocide and spray bottle to put it in, which would kill all the mould and he supplied some anti-mould paint additive to ensure that it did not come back after I redecorated. The other item he sold me which is shown in the centre of the photo on the right is ‘Insulating Paint’. When he mentioned it I said, ‘Pull the other one’ thinking it must be like the ‘long weight’ apprentices were sent to get from the stores or the ‘striped paint’ they were sent to the shop for, but Chris had a demonstration area in his shop and showed me how warm the wall was where it had been painted with insulating paint whilst the adjacent wall, not 10cm away, was stone cold. He also explained how it worked, reflecting the heat back from my hand or the room in which it is used, reducing the likelihood of cold spots – he suggested I put this on the wall under my bay window as when he did the survey, he noted it was 5 or 6 degrees colder than adjacent walls, due to previous remedial works and the proximity of air bricks on the outside of the bay. So, the bay has now been cleaned up, painted with insulating paint and then overpainted with ordinary magnolia with the special anti-mould additive (small bottle on the right above).
Having cured / killed / cleaned / got rid of the mould, the challenge was to stop it coming back and Chris sold me a bunch of extractors to make sure that humidity levels did not build up to the levels they were before. The 1st thing to be installed was this nifty Positive Input Ventilation (PIV) unit shown here after installation. It hangs in the loft space, draws in dry air and gently wafts it in to the upstairs landing creating a little airflow where there was none before. (And for those who like numbers, it pumps in 30 litres per second and consumes 5.1w of electricity – so negligible cost to run).
If all works to plan, the increase in pressure on the landing will push air into the bedrooms and the increase there, will push (damp) air out through the trickle vents on the windows. I had a problem here as the uPVC windows did not have trickle vents. I called my double-glazing guy, Andy at South Coast Glazing Repairs who is always excellent and he strongly advised against retro-fitting trickle vents because, “to be effective you need to drill through the internal galvanised steel strengthening bars and if you do this, quite often you will get rust running into or out of the window 3 or 4 years later”. Given that my 2 alternatives were to replace the windows or to have a PIV unit that created no real airflow in the bedrooms, I chose to ignore him and retrofit trickle vents myself. If you can get to the outside of the window, it is very easy – takes about 20 minutes a window, and vents cost less than a fiver on the Internet. Worst case I will be replacing the windows in 4-5 years’ time, but to be honest, they were there when I bought the house and modern double glazing is so much better than the old stuff, I will probably need to replace them then anyway.
Next thing that needed attention was the extractor in the bathroom. What was there was only 4 years old and when I specified it, I asked for a high output humidity sensing extractor which also came on when the light was on.
Chris advised that extractors today run all the time and come on in ‘boost mode’ either triggered by a light switch or humidity. I was worried about the noise of ‘being on all the time’ but Chris showed me several units in the shop which all seemed silent – so I went with his recommendation and the electrician installed this one – it looks much better than the one it replaced and has that snazzy blue light which comes on when it is in boost mode.
It sounded a bit noisy but the electrician had installed it with the trickle speed set at 13 litres / second. This was quickly changed to 6 litres per second and it is now silent except when in boost mode (11Db in trickle mode and only 2.5w power consumption, stepping up to 23 litres/second in boost mode and 26Db)
The final piece of kit I came away with is pictured left – another extractor you ask?
Yes and no is the answer.
The electrician installed it in the kitchen, it runs all the time quite silently AND….. and this is the good bit – it blows air out for 70 seconds, then sucks air in for 70 seconds and then goes back to blowing again.
The air coming in and out passes over a honeycomb, which stores any heat so instead of sucking out warm air and blowing in cold air, the heat from the extracted air is held and used to warm the incoming air, thus ensuring a change of air and continual freshness without losing any heat from inside to the outside or needing expensive heating elements. Clever eh?
To complete my purchases, I bought some humidity sensors.
The one on the left below is mine and gives me an accurate reading of the humidity in any room in which I place it – very useful when assessing or inspecting properties. I bought a few of the ‘happy face’ sensors and have left them in the rooms of tenants who I suspect of drying washing inside or not ventilating their rooms – they give an easy and obvious indication of humidity levels in a way that can be understood and explained, which is ideal for my tenants and hopefully yours.
So, to end this case study – one final piece of information. You probably wonder why I call him ‘Damp Man’ and compare him to super heroes when you probably think he saw me coming and sold me a load of stuff and emptied my bank account in the process. Well, you could not be more wrong.
Thanks to Chris, all of my damp has been eradicated, my décor has been restored to its original splendour, I am confident that my mould will not return and the air in the house smells much fresher and nicer AND, it all cost me less than £500*. Where else could you have bought such a comprehensive solution covering all of the bases and for so little? That is why I rank him alongside Superman – so follow my lead and if you have any damp, mould, or similar, get yourself over to Gosport and see Chris at Alliance Remedial Supplies.
At his facility in Gosport Chris has a demo area and facilities for training as well as a huge range of products to cover all of your damp, mould, condensation, tanking, waterproofing, repairs, treatments and drainage issues, so if you are interested in a half-day training session covering everything you need to know about mould or damp and what options you have to eradicate it, do let us know by clicking this link and if there is sufficient interest we will see if Chris can accommodate us.
*I obviously bought at 2018 prices, PDPLA members get a 10% discount, mine was slightly higher as I am an LNPG member too, but the less than £500 was genuine and included VAT. My electrician was extra, but it took him less than 3 hours to replace one extractor in the bathroom, and to fit a new one in the kitchen plus the PIV unit in the loft, so no a great deal of additional cost there either.