rising damp

my surveyor said there was a rising damp problem in two walls of my period house. there is no obvious sign of damp, does anyone have a good recommendation for a firm to verify and fix, living in dalkey.

I’d post a request on the boards.ie building forum.

I would be very careful and do some research yourself. We found that some builders suggested modern solutions (such as damp proofing and dry lining) to our period home that could have led to more problems.

What has worked for us has been to remove ivy and flower beds around the house. We replaced them with rocks and gravel to give drainage (using planters for flowers instead). We lowered the outside so that the drive is no longer above floor level (over time it had built up). As we have been rennovating rooms we have used a similar method to the original floor with no damp proof course, where the air can circulate underneath the floor. We have put concrete on steel decking and then added insulation and flooring. This has meant digging out the floors lower than they were originally but it has made a big difference to rising damp.

This might not be pratical or work for you but there is a lot of information and ideas on the internet that other people have used. Sometimes you can combine old techniques with new technology. I would recommend that you check out any work that is suggested before you give the go ahead. With no obvious symptoms it’s probably more important to get it right than get it done quickly.

One thing that I read about period homes is to always make sure you can easily undo work done in case you get it wrong. There are probably some good builders out there but no one has the same interest that you have in your house.

thanks for all the info


My parents had a rental house, old construction, where there were damp patches in some of the rooms. The first guy they got in was an “architect” (i.e. business cards but not degree) who had managed an extension for them some years ago (successfully). He brought a builder, and immediately started talking about dry-lining the walls for insulation etc.,. This made no sense to me as the walls were never insulated before and the damp was a new problem.

My partner’s an architect (no business cards, but with degree) but not practicing. She was very skeptical of the insulation plan, and thought it sounded both rather expensive and was not clear how it would fix the problem. Could also have led to a condensation point between the layers of the wall-fabric if you got unlucky.

Finally got in a reliable surveyor that my brother had used on a house-purchase (semi retired I think). He judged one damp patch was bad chimney flashing, so suggested getting a roofer to investigate (roofer found and fixed that). Said the rest of the damp was because people had overfilled the rooms (stuff stacked up walls, actually a type of ad-hoc dry-lining) and under-ventilated. Suggested asking people to open windows for a half hour each day, and putting in a small vent in each bedroom. Also recommended washing walls with dilute bleach to eliminate mold spores and repainting for cosmetic effect.

One observation: it seemed a pain at the time that the surveyor couldn’t/wouldn’t recommend any tradesmen to do the work (when really pushed, he had a couple of names but they were phenomenally busy, much too much to do small stuff like 2 vents), but it may also have contributed to the fact that his advice was conservative, in any case a good idea (e.g. wash the walls, open a window!) and cheap to implement (and pretty reversible as you suggest). The first guy would have had us taking down or replacing cornicing, insulating all gable walls, and maybe leading to further hidden problems in the wall, but there’s a strong chance he’d have got commission or finders fee from the favoured builder he brought along.

Excellent responses all round. Another thing to consider is if the brickwork was ever repointed with the wrong, unbreathable material at some stage in the past, e.g. sand & cement in the wrong proportions rather than a lime base mortar. The rule of thumb is that old houses need to ‘breathe’ whilst for modern comfort levels you need the best of work done to eliminate draughts, not an easy job for a builder to reconcile.

google “French Drain” damp etc

ihbc.org.uk/guidance_notes/d … Drains.htm

there have been posts on Lime mortar etc here too

HI retiredpaul,

I am currently renovating a period house, which is also listed, so the job is being supervised by a conservation architect. I second the points made by other pinsters about the inappropriate use of modern plaster, cement etc which can trap water inside the walls of old houses and also about ensuring you have adequate drainage.

In my place the damp issues are due to a high water table, coupled with the fact that the house has a basement level, rather than any of the above. So I am having to stump up for a tanking solution. My neighbours, who live in an identical house to mine, have faced the same issues and use this company to sort them out:


They highly recommended them, I plan to use them too but as my damp proofing works haven’t started I can’t give you an opinion on them.

You see unless you rip out the all the soil of Ireland, re-import some super permeable soil and stop it raining so much, Fianna Fail will rise again and again.

Oh wait. Sorry.


Before you engage anyone to do any work at all, I’d check out what this guy has to say. He’s an expert in London of Georgian and Victorian buildings and architecture and a lot of what is called “rising damp” is really just a massive con … it can be caused by simple things such as vegetation growing too close to the walls of the house or blocked ground level vents. He has a number of videos on youtube where he looks into bodged jobs and so-called rising damp, it’s a bit of an eye-opener and it might save you a few bob.