i'm having the same issue in 2 rooms, not sure if want to use sealer, waterproof paint or what else to solve it...

Ai yo! Dont you know there is something called gravity? Unlike power wiring and water piping, aircond drain pipe dont go horizontally for too long a distance! Drain pipe as it is called is to drain water quickly as quick as possible. By having it runs horizontally for too long distance it accumulate and retain the chilled water inside it instead of being drained immediately. Having chilled water in the pipe it condenses whatever moisture come in contact with it which include the moist air from your living room and in the inside of the concrete (wall). When water vapor condenses it not only wet the pipe/concrete it also creates a vacuum in the concrete. When there is a vacuum it sucks more water vapor to it and further condensation take place and wet, wet, wet, suck, suck, suck and hell lot of water than any other places.

Concrete is like a sponge with lot of capillaries created during curing or setting called hydration. Hydration is the process of water in the wet concrete drying/curing leaving the concrete mix via evaporation. During the process it created a lot of capillaries, tiny straw like tubes or holes for the water vapor as conduit to escape. Imagine there are thousands or maybe millions of capillaries. Though water cannot pass via these capillaries (unless the real big ones) water vapor can. Water vapor present in cured/dried/harden concrete as well and when your drain pipe get chilled the vapor condense on it. When gas changed to liquid, from a big gas volume to much smaller liquid volume it created a vacuum and more vapor is then being sucked toward it by the straw/capillaries. Moreover, your wall is one foot below your neighbor and next to it is either concrete or sands or mud or all of it that contain lots of water or water vapor are drawn to the pipe.

Think again, when you have a glass of icy water on the table, the outside of the glass will soon get wet in minute and so wet that it drips on the table. So do not underestimate the contain or amount of moisture (water) in the "dry" air and what's more in concrete and soil, sands or mud in the ground.

Drain pipes are to run at angle or slope from source on the high side to the bottom drain side, never flat or horizontally. If unavoidable then you got to have insulation.

Yup I agree. But I'm not too sure how flat is too flat. Any ideas?

If you look at the picture again (probably need to look closely), it is not really flat. You can see at the 'difference' in height from the start of the 'horizontal' pipe all the way to when it exits the living hall to the grassy patch.

It is very marginal. Hard to see, I use the sockets as guide and still it is very marginal. Moreover it is pvc not smoother and straight stainless steel pipe. PVC pipe bends and during installation are easily forced into the imperfect dug channel. So many factors when it is not in great angle diagonal. Not forgetting you have 2 L sockets at toward the outside where you drilled hole piping it out and sure it is flat, you never know if it is flat or at an angle? Only you can go and see but it is all concealed.

Anyway, not arguing how flat is flat. This only one of the possibilities. Also, the water from aircond is not clean, it has dirt not filtered by the aircond filter and will be in the water. Meaning these dirt can accumulate over time in a flat pipe, but again it is new.

Not to forget one other possibility. When the pipe is concealed the concrete is new. If you do not leave it for a month or 28 days to be precise before painting, the concrete is not fully matured and still have plenty of water evaporating bit by bit and can discoloured the paint or have water marks.

The pipe seemed to be shallow from the picture, why dont you switch on the aircond over few hours and feel the temperature or wetness differences between there and the wall above the sockets, same time enjoy your new air conditioning. You got to find out the source of the problem or eliminate other doubts before you can find solution and rectify it. By the way, there is a sticker thermometer you can use to measure the wall temp by holding it to the wall. you can find them in aquarium shop, they use it to monitor aquarium temp by sticking it on the glass tank. see pic below

Awesome idea. Will do this!

How would you suggest, step by step, on how to best solve the problem? The one I currently have after looking through the posts would be:

1) Rehack the piping area + slightly larger coverage (+1 ft)
2) Cover with waterproofing cement.
3) Finish the wall again properly. Mind telling me the breakdown? Sealer / undercoat (any difference?). How about the join material, skim coat, base coat, actual layer etc etc. Apologies, noob alert.

Going thru your posts again. I would say it is confusing as far as chronology is concerned. In order to know the problem is first to understand the chronology events. Then only find the solution. Here I try to understand and you have to correct me.

1. Before you hack and installed aircond drain pipe there were no water marks at the tile skirting as it was vacant for 3-4 months?

2. The water mark appeared after you lay the drain pipe, patch back the hack areas, painted it and 2 months the water marks appears even though you did not swtich on the aircond during the 2 months?

3. You then scraped away the paint and repainted it immediately and the result?

If it is (1), then it has to do with the drain pipe.

If it is (2) it is complicated. then (a) it is probably you painted it immediately after patching back when the concrete has not matured (before one month). (b) It could also be due to capillary action and present of a lot of water from your neighbor higher ground soil especially when it was painted 1 month after patching up and © it could be some areas of the hacked channels was a bit over hacks broke thru your neighbor wall with some small holes allowing water coming thru easily to your side of wall. This could happen when only one side of bricks are plastered (your side and your neighbor is side is soil, sands or debris or mud) and the bricks are not fully covered with concrete completely between stacked bricks completely sealing your side of plaster wall, as your wall is lower than your neighbor walls which is not plastered.

So, tell me which is correct, arrange your chronology events correctly and I tell you the corrective actions, step by step. This is most important to determine if it is due to drain pipe or present of water from ground.

Lol, it's very possible to be condensation.
First thing i see when you pipe your aircond in the wall without any insulation, it's definitely the problem. Maybe you seen others doing it, they might also suffer the same problem as you. unless they dont use the aircond for long duration. Even with a slanted pipe flowing out fast, you might have the same problem if you turn on the aircond really cold and for long duration.
Your aircond guy isn't doing their best at fixing your pipe. I seen mine insulated with rubber type material and some with spongy type of material over the piping.
Having any sealant or waterproof paints wont fix your problem. You gotta fix the piping issue. (Of coz make sure the problem isn't pipe leakage first)

This post has been edited by Untitled2: Dec 6 2013, 01:45 AM

Paint flaking off the wall is common along split levels between floors.

The 'wall' which is actually the exposed ground beam. If the ground beam is not treated with waterproofing where it is in contact with the earth, the moisture can penetrate through the concrete.

Waterproofing on the inside would not be effective as any coating on a damp substrate will not hold.

I don't think there is any effective solution to this.

another suggestion

drill a hole into your wall. this will tell you if the water is coming form inside of the wall or just the surface.

if water is from inside your wall then the hole will have dripping water after a few day as water accumulate and come out from the weaker hole opening.

please drill above your air con pipe and NOT at the pipe OK ... just in case you forgot.

Apologies for the late reply. Here's the chronology.

[2012 August] Keys received.

[2012 September] Defect work by developer. At this point, looking back at even older pictures (yay for documentation!), it seems like there were tell-tale signs of watermarks, though nowhere near as bad as now! Note that at this point, the original paint has already been there for few months, and it wasn't as bad.

Observe how it was also happening at the lower part of the wall, across the living hall.



A close up to one of the problematic areas:




[2013 February] Vacant for a long long time due to end of year, CNY and just timing issues. Work was restarted and hacking done to install aircond piping. Cement work done to patch up the wall a few days after that, around end of February

[2013 March ] Paintmen came to skim coat the walls only, around the end of March.

[2013 June] Work was put on hold due to timing issues (need to install timber floor before actual paint job), and also another defect found at a different area of the house. By June 10, work was restarted, and this is when paint is applied. At this point I didn't notice any watermarks on the wall (but it was just skim coating).

Aircond men then came around June 15 to install aircond.


[2013 August] I started to notice the watermarks at the living hall. They're probably worse than the ones I complained about during the defect report, but they're not as bad now. From June onwards sometimes I would visit the house *once* a week, at times turning the aircond 1-3 hours.

[2013 September] Scraped the peeling paint and repainted the wall again. I stopped using living hall aircond from this point onwards.

[2013 November / December] Messed up as per the posted pictures!

My gut feeling is
- the water problem was always there, even during VP. That's why I had to file some defects.
- the hacking for aircond piping worsened it. The hacking probably took out the 'good layer' of the wall which was holding back water to some extent
- the cement job to cover back the piping was never as good as the original wall / 'good layer', hence we see the paint deteriorating even faster!

How do you suggest I fix it?

Look like the wall already having this issue when you got the key. The bad paint markings you bout could be the issue already.

Great info Boyan,

What your gut feel is correct. I'll come back later and recommend some solution.

!st, The Cause and Effect.

1. Your house is lower than your neigbor by 1 foot.

To save money and effort (work) the one foot below your neigbor was not plaster or simply "cincai" plaster since it is underground. This makes easy for underground water to seep into your side.

Anyway, even with good plastering ground water has no where to go as the floor is tiled. Water if not flow down by gravity will go up by capillary action or evaporation and condensed at the top solid layer where there is no way out. The only way out is to your side of wall, the one foot side. But then you may ask what about houses with same level? While when it is same level the water will go up all along the joint wall but not in as big volume. Under normal circumstances the evaporation continue right up to the surface of the wall through the paint (which is breathable. Breathable means vapor can pass thru) with little condensation. Even when there is a lot initially, by the time handover key (vacant possession) most of it has dried up as painting are usually done last. But for your case because it is one foot below neighbor ground, you have not only evaporation but a lot of capillary action as well. Anyway, even if you do not do anything under normal circumstances it will eventually dried up and you will not have water mark in future, but that will take some 5 years on average. That's is provided it is not make worse by your chilled aircond pipe as you have not one cause but 2 causes as below (2).

2. As explained in my post earlier, the chilled or cold aircond drain pipe draw in or suck more water and water vapour to the pipe due to condensation gas to liquid and the vacuum effect, make worst the situation. As you also mentioned the barrier to water had been made worse by the hacking for the pipe. The back of the pipe against the wall is not re-filled compactly with concrete.

Now, here is my suggestions. Let me start with the step you should do.

Step 1. Re-route the piping. That will solve cause (2) above. See picture below.


This will allow the chilled water to flow the minute it drip right up to the outside of the house and the chilled water has no time to cold the pipe for any chance of water condensation to take place. Moreover the high dried wall has little or no water vapor in it. If condensation has to take place it has to be from your living hall air's water vapor. Your living hall air as you swtich on the aircond, its water vapor or humidity has been taken away by your aircond! That is why your aircond dripping cold water (if you understand how aircond works you would understand this).

Step 1-1. cut the existing pipe somewhere shown in the picture, if not remove all of it till the manufacturer's flexible aircond drain pipe (that come with the aircond is even better) if it is not Class 7 pvc pipe.

Step 1-2. Buy a long one inch Class 7 pvc pipe as the drain pipe. Class 7 has the thickest wall of all available pvc pipe classes. The thick wall itself provides heat insulation. There is no need for extra pipe insulation. Save money and work digging a deep and wide channel into the wall. Trust me. Never buy any other class especially Class 0 which aircond people usually use to save some little money and easy to work with. Class 7 is expensive comparatively and more stiff (hard to bend and to insert or fit into hacked channel)

Step 1-3. Do not start hacking. Make bend to the pvc pipe first as show in the above picture. Use gas stove heating up the pvc pipe soften it and make the bend shape, the aircond guy should know how to do this. Make wide bend not sharp bend so as to have smoother flow of water.

Step 1-4 Then draw the outline on the wall to be hacked and hack you go and the pipe should be at least half inch
inside wall surface. One inch is ideal. One half inch is ok. Too deep means a lot of hacking. The wall is 6 inches wide. Old house use to have 2 bricks wide wall, nowadays one brick. That mean you owned only 3 inches to your side.inside wall surface. One inch is ideal. One half inch is ok. Too deep means a lot of hacking. The wall is 6 inches wide.

Careful with this while hacking

1. There are at least 2 set of wire running along the wall and there shouild be a column for every 10 feet of wall, measured from the front column so roughly you know where it is. You have 2 column in this case as mark in the picture. So, do not allow the worker to use circular saw to cut the wall and accidentally or purposely (since they know) cut the wires. As for column it is harder to hack as it is a reinforced concrete that is not bricks but stone concrete and rebars. The circular saw make cutting job easy but it will cut the wire and rebar no matter how careful they are.

2. When rebar of the column in the way anyhow you must not be convinced by them it is ok to cut. Becuase they don't owned the house but you do mean they dont care if it is weaken. Go hack deeper avoid the rebars, the pvc pipe can bend. Like I said, they use class 0 becusae they can bend easily. They have to use heat again to bend the class 7. The vertical rebars MUST not be cut, the horizontal rebar that tied the vertical rebars can compromise(cut) but if can avoid best don't cut it.

Step 2....to be continued....

Step 2 :

2-1 Hack and remove the old drain pipe that run flat. Also hack as much the pasted concrete that concealed the old pipe.

2-2 You can leave the old pipe that run straight down and hack out only the bottom part at least 1 1/2 feet from the bottom. Use PCV glue and PVC end cap, glue the bottom end of the cut pipe. Now, this pvc pipe which has no use and is going to be sealed in the concrete forever, make use of it, you can make your time capsule. Yg ou can write something, about yourself, family and photos. Also if you have one sen coins, 5 cent coins and one, two, five and ten and 20 ringgit notes and some small staff you can insert in. After 100 yrs this monies will no longer in circulation, even now the 2 dollar notes are no longer in circulation, so is one cent coin. But remember once you sell the house it is no longer yours. Then glue seal the top end with another pvc endcap.

Step 3: plastering and sealing with waterproof.

3-1 fit the new drain pipe in place and test run the aircond. With the sticker thermometer now you can test and record the drain pipe temp. Switch on for 3 hrs and hold the thermometer at strategic location or along the pipe. See for yourself it there is any condensation and the temp. My guess is there should not be any condensation.

3-2 Plastering. Do not let the worker or contractor mix their own plaster. Go buy ready mixed plaster. Two things to look for.

3-2-1. Go for plaster with waterproof properties with could be more expensive by RM1 to RM3 a 25kg bag. One bag RM11 to RM13. It is written in the bag. Plaster with waterproof has admixture properties or waterproof property. Admixture = waterproof additive where there are plastic or rubberised property in the concrete mix and uses less water and better workability. (will explain that later)

3-2-2. Depending on your wall texture. If it is rough surface choose the rough one to match your wall surface. If the wall is skim coat then choose the finest plaster. It is state in the bag.

3-3. There is no need for further waterproofing to conceal the new drain pipe. The waterproof plastering is good enough, subject to proper plastering skill. Few things to watch out.

3-3-1. When mix the ready made plaster powder with water, use as little water as possible into a paste. The more water you use in the mix the less waterproofing it is. Water in the mix creates the capillaries in the concrete during curing/hydration, Using too much water create more and bigger capillaries. When less than usual water is use the capillaries is not only lesser but also smaller, so small that water cannot seep through. Only water vapor can "breathe" through, therefore, waterproof. The admixture has the additive which allows uses of less water. Workability mean there is enough water to make the concrete mix paste like and can be work on. More water = more workability but less waterproof. That is how waterproofing is achieve with using admixture with the need of lesser water besides it has the plastic or rubber properties. But, never go and buy admixture and add into it. There is not need as it already has its formula tested. By adding admixture to the formulated plaster may work aginst it.

3-3-2. Curing time. The longer time taken to cure the better the waterproof. So, keep the place cold by shutting all windows and doors after plaster so no wind, no sun and no air circulation to slow down drying. By the way, the ready mix plaster that has admixture will dry slower than normal mix concrete. It is the admixture that slow down drying time and therefore achieving waterproofing.

3-3-3. To have good adhesion to the old concrete use a one inch paint brush dip into bucket of water and wet the hack channel and the drain pipe. Do not flood it, just wet it before apply you plaster cement. Without wetting the plaster cannot stick to the old concrete easily as the water of the mixture/wet plaster is sucked to the wall/old concrete and with too little water in the concrete mix no proper hydration process, the process is also affected and the plaster is not solid but loose.

3-3-4. Work from top to bottom. It is easier to plaster/work from bottom to top. The reason to work from top to bottom is to avoid adding water to the wet plaster when wetting the hack channel. When you work from bottom as you wet the top portion of the hack channel with the paint brush, water from the paint brush drip to the already done plaster at the bottom and therefore adding more water to the still wet plaster and the plaster become weak and less waterproof.

3-4: Plastering and waterproofing the old hack area....to be continued...

3-4: Plastering and waterproofing the old hack area:

I would use Sika-top 107, as I have experienced it waterproofing my koi pond. It comes in 25kg bag and has 2 parts. One part is cement powder 25kg and the other is white milky liquid (susu). For proper mix the 25kg powder mix with the whole can of liquid. But you probably need only 10% or less of the 25kg. You need 2 coats. Do it on the hacked channel and not after plastering. this is how you should supervise the workers:

3-4: Correct mix.

3-4-1 Use a weighing scale, weight 1.25 kg of the powder which is 5% of 25kg.

3-4-2 Similarly try to pour 5% of the white liquid, How? You weight the whole can of the liquid and divide by 20. Pour some liquid to a small light weight cup and weight it if it is 5%. Anyway, it is not accurate because we do not take into consideration the weight of the plastic container of the liquid and also the weight of the cup. But that is the best you can get, otherwise you divide the whilte liquid container by 20 layers. Still I think it is better to use weight and cup. You can cut a mineral water bottle use it as the cup, it is light weight.

3-4-3 Mix well into a small plastic bucket/container. Again you got to wet the hacked channel first with the one inch paint brush. Use another on inch paint brush for the application of sika top, dip the brush into the bucket of sika top mix and brush it into the hack channel like you are doing painting. It is easy as that. Do not worry that the sika cement does not stick to the concrete but to the paint brush. It will, because it is very sticky so be careful not to touch anything. It dry fast and hard to remove even on your hands. This one coat give one or two or 3 mm of sika on the hacked channel.

3-4-4. You need at least 2 coats of sika for proper waterproofing. Repeat above. 2 coats is to make sure you cover all areas properly as some areas on first coat may not be perfectly or sufficiently covered. This will make sure no water can seep thru where sika covered. Imagine I applied 3 coat to my 3 feet deep koi pond and it is leak-proof!

3-4-5. By the way if you are using this sika top, might as well apply it to the drain pipe as well because it is harder for the plaster to stick to pvc pipe, with this sticky sika top it stick well to the pipe and then to the plaster.

3-4-6. Now, it is time to plaster it with the ready mixed plaster and job done. This sika plus good plaster should solve the water mark problem as it only allow little water vapor to pass thru them and reduced volume is not a problem. Remember concrete need to breath, you should not seal it completely. if you seal it (totally) the seal will someday be broken or the concrete inside will be weaken.

Step 4 : Painting.

4-1 Wait for at least a month for the plaster to cure/dry. Do not think that because your paint is water base therefore wet is ok. It does not work that way. When you paint on un-cured concrete (less than a month) even with water based paint, the paint dried first and presumed harden but your un-cured concrete still evaporating water heavily and because it is evaporating heavily it has not enough time to be evaporated/breath out of the paint and condensed underneath the paint and discolor the harden paint and the paint expended with water marks.

4-2 Primer paint. I am not good in painting knowledge but this is a little what i know. Primer paint or undercoat is advisable as it provide better adhesion to concrete surface. As such it increase the surface paint durability. It also protects the top paint or itself from peeling due to water vapor (evaporation, as concete breath all the time) since it stick harder to the wall than just normal paint.

Do not hesitate to ask any part you have doubts.

Cheers

stevie8, I just wanna say, your posts - are awesome and informative.

I have only two questions.

Are you a contractor, and if you are, would you take the job?

If not, can you recommend someone who is competent enough to do whatever you have painstakingly jotted down for me here? (I really do appreciate it!!!)

Sorry Boyan, I am not a contractor. Am a DIYer and I also don't have someone to recommend as I do a lot of small jobs like this myself. Major work like reno wet work I will not diy cause it required professional expertise. The major job I did is building my own pond and a pergola also posted in this forum.

This is my DIY pergola in this forum: https://forum.lowyat.net/topic/2641338

I also posted about sika top here is the post to help you understand more: https://forum.lowyat.net/topic/2905725/+40

I am not asking you to DIY but with the knowledge you can supervise your contractor so that they do not cheat on your job or give you a lousy job. The problem for most people is they go for a solution but due to improper skilled job or cincai job, they then think that it was a wrong solution, but the fact is that it is not a wrong solution but the workers did not do it properly or correctly.

Wah kao, very pro and informative. I believe not many contractor (or non) or aircond man will attempt such job o.O" One thing about Malaysia is that many contractors aren't professional, they came to the business by "common sense" which is why it lacks professionalism for a perfect job..

Plus, i think the cost if you were to hire a contractor to do such job should be quite high. Malaysian contractors always use these words "Okay one" , "No problem" and just Bantai only. lolz some do fix the problem but I do agree with affecting the house structure pillars.. But I think everyone does give in to the contractor.

If anyone find such great person to do this job, let me know, i might have things in the future that might need such expertise. haha.

totally understood stevie8. hats off for your DIY experience and knowledge.

You also know not many people want to take up these kind of laborious jobs ever since if they have a choice as construction workers, mechanics, farmers, fishermen, plumbers, etc. Only those school dropouts having no much choice and now only indons. Since they never learned by the books they learned on the job from their sifus. Even now we have no construction schools and technical schools are not popular but I did see some mechanic colleges now coming up with Alex Yong former F1 picture in the advertisement. How much can you rely on school dropouts and indons? We have to trust them you know because we have no choice just like when your mechanic say this OEM or non original part is good for your car and 20% of original price with 3 months warranty you got to trust him especially when he said eversince he used this part for all his customers no one came back and complained! Ya lor, after 3 months or a year later problem emerged and you went to another mechanic shop. What's else can you expect when you pay only 20% of the price?