Many people that own a property have never had their drains inspected. Some don’t know if they have a soakaway or not. Whilst it is well documented about drains, can be a cause of damp issues I have never seen anything published in regards to a soakaway causing rising damp issues. I tend to find that a blocked soakaway can cause excess moisture to occur within a sub floor void, and can be the cause of woodworm, and even fungal timber decay like wet rot or even dry rot. I’ve seen many blocked soakaways cause rising damp issues, and even flooding of the cavity within the wall. It is imperative that when trying to solve a damp issue, is that you identify and fix the root cause before treating the symptom. Some really good info can be found about soak aways in BRE DIGEST 365, and Approved document H drainage and waste disposal.
Please see the video below where I explain about soak aways and go through some of the issues I find. Don’t forget damp issues can still occur because of drain defects, and even bodged up French drains.
If you need a professional damp survey you can contact me enquiries@completepreservation.co.uk and send me some info of your damp problem. Please be aware I don’t offer free damp surveys.
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This is a very interesting opinion about these types of drains. It’s funny now after watching the paint removal video I find myself sat in traffic looking at properties wondering how damp the wall is. I follow you on Linkedin, and seen your post on this subject, and thought it was strange how another surveyor disagreed with you. Keep up the good work Ross
Whilst it is interesting I do hope that it does point out the basics in to why these French drains can cause more of an issue in regards to rising damp issues. As for the paint removal videos, again hopefully they show what I would think an averagely competent surveyor would recommend in regards in trying to help solve the damp issues. I’m pretty sure I know who you mean by ‘another surveyor’. I don’t know the chap personally… it’s a shame he doesn’t explain why he doesn’t agree with the poor advice given out. From the feedback I have been given, everybody agrees with me, and that is also very clear on the post.
What’s the best way to fit a dpc under a bifold door and bridge to existing dpc under the walls without overlapping. Best way I can think of is to use liquid dpm under the bifold and on the dpc on the exsisting dpc, then apply butyl rubber mastic to the edges of the exsisting dpc (liquid and butyl mastic soaked onto exsisting dpc) and then lay on the new pdc under the bi fold and then deal with more mastic. All I ever hear is you need to overlap but it’s not always possible.
Hi Terry without seeing it I can’t really give advice, linking it with a something like a membrane tape used for below ground waterproofing sounds an option 🙂