This is a very common problem. There are plenty of water. It is not termite. It is the other way round. Water attract termite.

You cannot get rid of the water as you do not know where the source of water from. If no new source of water present then it will dry soon and the problem solved by itself due to capillary action and evaporation.

If it is due to when no polythene sheet laid below concrete slab then it should happen to all areas and not only the isolated areas.

The easy and cost effective way is to waterproof the wall up to 1 foot above the highest water mark. When the source of water is continue feeding that area and if you only waterproof up to the problem areas then new patches will appear above the waterproof areas as by nature accumulative water need cycle. meaning it has to go somewhere by capillary action and evaporation. By waterproofing higher hopefully instead of water getting up higher it goes else where by gravity like to your neighbor soil and find a way out somewhere else. Gravity is your friend, so waterproof higher and do the job once.

This post has been edited by stevie8: Dec 4 2013, 01:28 AM

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.

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

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.

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

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.

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?

Ya about car industry, this is where some people are jumping on our misery for new business opportunities. They now do not allow import of original used parts called potong with the excuse it is not road worthy but allow sale of new non-original parts made in Malaysia, Japan, Thailand whcih are sub-standard. I rather use the potong parts when ori is too expensive than those sub-standard new parts. And soon they want to outlaw old cars. Some already went to the extend of doing clash test to convince us saying old cars are not safe from their clash test. Of course new cars come with newer safety measure better than yesterday technology. It is all excuses to support new cars sale.

First you need a chisel and a hammer. Chisel with flat sharp edge as in the pic or a sharp end like a pencil.


You may also need a circular saw to make hacking easy but you must know how to handle it.


The picture you see is sawing wood, change to concrete blade saw.

Circular saw spin very fast and you must have steady hands and practice. Besides, as said earlier if you do not know how to use you might accidentally cut wires and rebar. To avoid that this is how you should use it:

1. draw two parallel lines the channel you want to hack.

2. Adjust the depth. You must not go deep but bit by bit. the first depth you estimate the depth of the plastering. To do that you hack using chisel in between the 2 lines middle of the channel and review the bricks. From here you know how thick is the plaster. With this shallow depth you should not have cut the rebar or the white pvc tube that concealed the wires. But when you can guess the wiring line with all precaution you shoiuld not saw that areas but use chisel instead for that small areas.

3. Saw the 2 lines and followed with another at the middle along the two lines and then a few more between them.

4. with 4 or five cut lines you can now use chisel and hammer and dig a shallow channel.

5. Next with chisel and hammer hack as deep as you can at the middle of the hacked channel.

6. Now you got a deeper middle channel and still find no rebar or wire, means you can adjust your circular saw blade deeper as the mid deep channel. Now, saw the two lines with this depth and repeat 2,3,4 and 5 till you get your desired depth.

See, so easy.

There is no use for drill except for digging out of house toward the end.

Cheers.

Precaution using circular saw on concrete:

1. Concrete powder fly as you cut, so no fan, no aircond. Open all windows and doors. Cover furniture, tv, computers as far as kitchen. Close all room doors except toilet. Still you will find that your whole house is covered with white powder it is no use closing all windows and doors so open it to allow as mcuh powder to fly out of house.

2. Wear goggles or safety glasses, dust mask is a must.

3. Use both hands and ready for kick back. To avoid kick back go slow and patient. moving slowly cut from bottom to top. A circular saw will almost always kick straight back. Watch your body position. Keep slightly to the side, and never keep a hand behind the blade. Never turn corner, it will sure kick back.

4. Be aware of the location of any power cords, keeping them behind the path of the cut at all times.

5. Do not work once you are tired or sleepy. Get rest. and take a break in between cuts. Also to allow flying powder to settle so that you can see properly. Rest or break outside of the house for fresh clean air.

6. Stand on steady ground or solid support.

7. Clear your other tools in the work areas, keep the tools away like the pencil, ruler, pipe etc or leave it a side at a corner like the hammer, chisel.

can it be used on old concrete like roof tiles?

How long ago?

After some years it will stop as the water dries underneath unless new water source is introduced like underground broken pipe or broken drain next to it allowing rain water to seep into the ground more than usual. Under normal circumstances the front of house have drain that drain roof rain water to big monsoon rain outside the house.These drains could be yours but if it is your neighbor's then you got problem if they choose not to repair the drain big headache for you.

Also when concrete aged it get harden and gain strength and at the same time its shrink and its capillaries getting smaller and waterproofing improved. When the water marks are not getting worse, it is time to repaint those areas.

Maybe applying Surfapore C kaw kaw could help with first removing the paint layer. That reduces water vapor coming through and condense at the paint layer. This is for Surfapore people to comment and give assurance.

That will require a lot of your product like few liter and your product is not cheap.