Hi, Just moved into a house with a bit of raising damp across my lounge back wall. Damp specialist recommended a chemical DPC injected in the wall and re plaster 1 meter. I've just removed my fireplace to investigate getting a stove fitted. Under the hearth cement was laid on the sub-floor to the level of the parquet floor and the top slade of the DPC. Damp has gone directly into parquet from this and also breached the DPM as it broken down and expanded with time. Spoke with a flooring company about getting the parquet restored and mentioned the damp and the room smells of tar when the weather is hot. Said this was the bitumen smell emanating from the cracks in the loose tiles and having a chemical DPM will dry the concrete floor also, causing the parquet to break down further and making the smell worse! Suggested a 'proper' job would be to lift the sub-floor and start again which i can't afford, or 1. Remove around 60mm of the parquet, clear what i think should be an air gap between the floor and the wall, put acrylic paint down on the lifted floor and up to the top of the DPC and use waterproof plaster on the bottom 1 meter of the wall. 2. Have the chemical DPC done and risk the parquet floor becoming unstable and smelling! What are your thoughts? I don't know if the damp is coming from the sub-floor crossing the filled air gap or in the other direction from a failed DPC Thanks, Andy
DPC has failed whole floor needs ripped up a start again. Use an Epoxy liquid dpm on the concrete or dig it all up new DPC and new concrete laid
Hi Adam, That's an interesting statement. I am a big supporter of MS/silane based products and I've not come across anything that indicates this to be the case before, and whilst I'm not for one moment saying I don't believe it, I would love to see the evidence to understand the methodology and rationale of the testing undertaken to establish this position. Hydrostatic ground pressure from under a floor without a DPC will not be held back by anything but a mechanical barrier if it's is great enough it will simply blow through surface applied materials. That isn't to say that a DPM won't work where there is no DPC as there may not be any or enough pressure to cause a failure and it would be good to understand how the various products work and which ones present the best chance of success/ the least risk of failure. Andy
It’s a full rip up new mechanical dpm and concrete, grind down after a week, wait 4 weeks, Rh% test, surface dpm prime and screed then bond down new wood, I wouldn’t do it any other way. Sent from my iPhone using Tapatalk
Have a chat with murexin MD and technical director Kenton At murexin buddy, he will run through all the science 01245407808
Thanks for the advise. Can you recommend someone that can do the work on the floor and restore the parquet? I’m in Bromsgrove, SW of Birmingham