How To Waterproof A Large Concrete Water Tank?

[thaibeachlovers]

We have a very tall concrete water tank as a back up supply. However, it is old, and has started to leak through the concrete. There is no way I can apply waterproofing from the inside, so need to do it on the ouside.

Is a paint on type waterproofing as available from Home Pro suitable? They usually say to apply it on the inside, but as said that's not possible in this situation.

Applying cement to the outside is also not really a viable option.

Thanks for any help with this problem.

[bbradsby]

Youre talking about a 'negative side' waterproofing retrofit, and it's not advisable, especially over a degraded, leaking substrate. Best is a 'positive side' solution, under positive water pressure to hold it in place against the substrate.

If the tank's old and begun leaking, thats a sign that the concrete is degrading unless water is coming through obvious cracks. But even then, based on age, I'd assume it's done, and no [especially negative side] coating will hold together & seal highly- degraded concrete:

Plan:

1. knock down the tank walls & cap and install a new plastic tank on the existing concrete slab if it's still structurally sound. get pro help if youre not a pro.

2. drain the tank, into a plastic one on the ground for your continued use if necessary, and apply an epoxy tank coating readily available here, on the positive side - that's the inside of the tank. Then use the plastic tank for rainwater catchment off your roof!

[David006]

Youre talking about a 'negative side' waterproofing retrofit, and it's not advisable, especially over a degraded, leaking substrate. Best is a 'positive side' solution, under positive water pressure to hold it in place against the substrate.

If the tank's old and begun leaking, thats a sign that the concrete is degrading unless water is coming through obvious cracks. But even then, based on age, I'd assume it's done, and no [especially negative side] coating will hold together & seal highly- degraded concrete:

Plan:

1. knock down the tank walls & cap and install a new plastic tank on the existing concrete slab if it's still structurally sound. get pro help if youre not a pro.

2. drain the tank, into a plastic one on the ground for your continued use if necessary, and apply an epoxy tank coating readily available here, on the positive side - that's the inside of the tank. Then use the plastic tank for rainwater catchment off your roof!

Agree .... replacement plastic tank is the way to go ....minimal labour and cheap as chips....

In NA I seem to remember waterproofing membrane type paint for below ground basement walls ...maybe only suitable for osmotic damp....

[thaibeachlovers]

Hmmm, that's disappointing.

I guess I'll have to check out price of new plastic tank.

No way I can fit through hole on top of tank ( too big ), and can't afford to pay someone smaller that may or may not do a proper job.

Thanks for advice.

PS. Does such a thing exist in Thailand as a flexible liner that could be inserted into the tank?

[bankruatsteve]

Hmmm, that's disappointing.

I guess I'll have to check out price of new plastic tank.

No way I can fit through hole on top of tank ( too big ), and can't afford to pay someone smaller that may or may not do a proper job.

Thanks for advice.

PS. Does such a thing exist in Thailand as a flexible liner that could be inserted into the tank?

If you're fixated with keeping the original tank, then try (as others have said) DRAINING it, let it dry, and get some small person to go inside and apply a good (I would go acrylic - but epoxy or whatever says "water proofing") based sealant. Follow the mfg recommendation but usually 3 coats and 4-7 days drying before filling it up with water again. BUT - if the tank is ready to crap out anyway, nothing is going to work.

[thatguy]

Doesn't look like this would help your current situation, but saw this stuff some time ago:

http://www.google.com/products/catalog?hl=en&cp=10&gs_id=2&xhr=t&q=epdm+liner&rlz=1C2GGGE_enUS358US455&gs_upl=&bav=on.2,or.r_gc.r_pw.,cf.osb&biw=1366&bih=643&um=1&ie=UTF-8&tbm=shop&cid=10028479490305800448&sa=X&ei=sFQtT_WVDI6v0AG-qPDQCg&sqi=2&ved=0CIABEPICMAI

one use I saw

http://www.builditsolar.com/Projects/SpaceHeating/SolarShed/Tank/Tank.htm

[thaibeachlovers]

Thanks for those replies.

[pgangell]

You could try this site - http://www.bondall.com. They are an Australian company and have an agent in Thailand. His email is [email protected]. I got some stuff from them to seal my concrete fish pond. Very good products.

[Crossy]

I can't help with products but I would caution anyone thinking of going inside a water tank (or any confined space) and using any form of solvent based product.

It does not take long for the solvent to make the air unbreathable, at the very least a fan possibly with a length of flexible duct (flat plastic tubing) should be arranged to get fresh air in to the tank.

[onionluke]

I can't help with products but I would caution anyone thinking of going inside a water tank (or any confined space) and using any form of solvent based product.

It does not take long for the solvent to make the air unbreathable, at the very least a fan possibly with a length of flexible duct (flat plastic tubing) should be arranged to get fresh air in to the tank.

Better include a rope to tie round the little guys waist for to pull him out with just in case he becomes unconscious .

[thaibeachlovers]

Thanks guys, but NO ONE is going inside the tank! No way I'm letting my wife go inside a 15 foot narrow tank, and there's no way I could check that a paid worker would do a good job.

I've got some sealer from home Pro, and when the tank is empty and dry, I'll paint it on the outside, and if that doesn't work, tough. It's not my property, and won't be living there long enough to spend a lot of money on a new tank.

So, my back up supply is in a lot of those big drinking water containers that I buy for my drinking water.

I was only going to try and fix the tank for my wife's sake, but it's not important enough to spend a lot of money on.

[swissie]

Quite a few folks seem to be "in the know" about situations like this. I have a similar problem and I have a post below that reads "Not tight water through in bathroom". Would anyone care to look at it and possibly give me some input?

Thanks & cheers.

[mikecwm]

http://www.xypex.com/

I've built big concrete tanks for water storage. Once the tank is finished we go inside (with a big fan forcing plenty of air in) and spray completely with a product like Xypex.

If works its way into the concrete and grows crystals that completely seal the surface and deep into the concrete.

Maybe if you took the top off the tank getting inside wouldn't seem such a problem. Plus it would be easier to vent while someone is in there. You could then put a top back on with a decent size access for future clean-outs etc.

[thaibeachlovers]

http://www.xypex.com/

I've built big concrete tanks for water storage. Once the tank is finished we go inside (with a big fan forcing plenty of air in) and spray completely with a product like Xypex.

If works its way into the concrete and grows crystals that completely seal the surface and deep into the concrete.

Maybe if you took the top off the tank getting inside wouldn't seem such a problem. Plus it would be easier to vent while someone is in there. You could then put a top back on with a decent size access for future clean-outs etc.

Hmmmm. The tank is only about 3 foot across, but at least 15 foot high. It has a heavy concrete cover on top, which would require hiring a crane to remove.

Going inside isn't going to happen.

[bankruatsteve]

http://www.xypex.com/

I've built big concrete tanks for water storage. Once the tank is finished we go inside (with a big fan forcing plenty of air in) and spray completely with a product like Xypex.

If works its way into the concrete and grows crystals that completely seal the surface and deep into the concrete.

Maybe if you took the top off the tank getting inside wouldn't seem such a problem. Plus it would be easier to vent while someone is in there. You could then put a top back on with a decent size access for future clean-outs etc.

Hmmmm. The tank is only about 3 foot across, but at least 15 foot high. It has a heavy concrete cover on top, which would require hiring a crane to remove.

Going inside isn't going to happen.

Have to say I haven't seen anything with those dimensions. If it's covered, then how does water go in? A crane? C'mon.. If you want to paint the outside, go ahead, it ain't going to work.

[transam]

You can buy plastic tanks and fix in tandem. Two or three linked together, easy.

[thaibeachlovers]

http://www.xypex.com/

I've built big concrete tanks for water storage. Once the tank is finished we go inside (with a big fan forcing plenty of air in) and spray completely with a product like Xypex.

If works its way into the concrete and grows crystals that completely seal the surface and deep into the concrete.

Maybe if you took the top off the tank getting inside wouldn't seem such a problem. Plus it would be easier to vent while someone is in there. You could then put a top back on with a decent size access for future clean-outs etc.

Hmmmm. The tank is only about 3 foot across, but at least 15 foot high. It has a heavy concrete cover on top, which would require hiring a crane to remove.

Going inside isn't going to happen.

Have to say I haven't seen anything with those dimensions. If it's covered, then how does water go in? A crane? C'mon.. If you want to paint the outside, go ahead, it ain't going to work.

It's homemade from concrete drain pipes stacked one on top of the other. A hole in the side at the top is where the fill pipe goes in ( not exactly rocket science ). I never said I WANTED to paint it. This post was to find out if there was a better way.

[thaibeachlovers]

You can buy plastic tanks and fix in tandem. Two or three linked together, easy.

Thanks, but I've spent more than enough on someone else's house, so the big water bottles will have to suffice till we leave. I add another every couple of days. more than enough for an emergency supply.

Thanks everyone.

[transam]

You can buy plastic tanks and fix in tandem. Two or three linked together, easy.

Thanks, but I've spent more than enough on someone else's house, so the big water bottles will have to suffice till we leave. I add another every couple of days. more than enough for an emergency supply.

Thanks everyone.

I'm talking about 2000 liter plastic tanks linked together. As many as you want and are cheap to buy.

[thaibeachlovers]

You can buy plastic tanks and fix in tandem. Two or three linked together, easy.

Thanks, but I've spent more than enough on someone else's house, so the big water bottles will have to suffice till we leave. I add another every couple of days. more than enough for an emergency supply.

Thanks everyone.

I'm talking about 2000 liter plastic tanks linked together. As many as you want and are cheap to buy.

Oh. Well unfortunately there's nowhere to put them anyway, which is why the present tank is so narrow and high. Thanks anyway.

[Kwasaki]

You can buy plastic tanks and fix in tandem. Two or three linked together, easy.

Thanks, but I've spent more than enough on someone else's house, so the big water bottles will have to suffice till we leave. I add another every couple of days. more than enough for an emergency supply.

Thanks everyone.

I can understand your situation but and there's always a but if your happy with the bottle situation and the landlord is not going to take anything out of your deposit by saying you haven't maintained the tank OK.

How long are you thinking of staying is the question for a relatively small cost.

The tank could easily be dismantle and a cheap 1000 Ltr black/blue cheap tank put in it's place.

Hope things work out anyhow. K

[bankruatsteve]

Well, since this one keeps going, I'll add what I was thinking before...

Since I now have the picture: a bunch of septic rings built up, yah? So, you should be able to easily tear it down and re-build, if you want. Guessing you (or local labor) could probably do that for less than a couple thousand baht. (?)

[Kwasaki]

Well, since this one keeps going, I'll add what I was thinking before...

Since I now have the picture: a bunch of septic rings built up, yah? So, you should be able to easily tear it down and re-build, if you want. Guessing you (or local labor) could probably do that for less than a couple thousand baht. (?)

Your probably right stevie boy, the thing for me is they use this system a lot in our village and I've never seen one yet that don't have some kind of leakage from day one probably because they don't pay out for a water sealer to apply to the concrete rings or wanting to wait for drying times etc etc.

Again right about local labour sorting it with only having to buy the cheap plastic tank, it could then be used right away utilizing the existing pipe connections.

Regards formey DelBoy Builders Corp, New York - Paris - Watford.

Edited March 19, 2012 by Kwasaki

[Kananga]

If its not your property why not just ask the landlord to fix it? If my house sprung a water leak I can assure you I would be on the phone to our representative to get the landlord to fix it sharpish, I would NOT be on a harness painting water sealant over some massive concrete monstrosity. Those things are a terrible eyesore anyway, better just to knock it down of you ask me.

Edited April 2, 2012 by Kananga

[thaibeachlovers]

Well, update on the tank. I had to wait a while till the water level went down far enough and the tank was dry.

I bought a tin of Acrylic waterproofing sealer ( I think by Bosny ) from Home Pro, painted it on with a cheap paintbrush and waited a few hours before filling the tank. So far, has worked 100%.

If it starts to leak again, I'm just going to get some flexible plastic sheeting and use some roofing silicone to make a patch.

[bankruatsteve]

Well, update on the tank. I had to wait a while till the water level went down far enough and the tank was dry.

I bought a tin of Acrylic waterproofing sealer ( I think by Bosny ) from Home Pro, painted it on with a cheap paintbrush and waited a few hours before filling the tank. So far, has worked 100%.

If it starts to leak again, I'm just going to get some flexible plastic sheeting and use some roofing silicone to make a patch.

Did you read the directions? I'm surprised if it didn't say to put 2-3 coats and wait 3-7 days before filling with water. (?)

[bankruatsteve]

Well, update on the tank. I had to wait a while till the water level went down far enough and the tank was dry.

I bought a tin of Acrylic waterproofing sealer ( I think by Bosny ) from Home Pro, painted it on with a cheap paintbrush and waited a few hours before filling the tank. So far, has worked 100%.

If it starts to leak again, I'm just going to get some flexible plastic sheeting and use some roofing silicone to make a patch.

Did you read the directions? I'm surprised if it didn't say to put 2-3 coats and wait 3-7 days before filling with water. (?)

[thaibeachlovers]

Oh, it probably did say something like that, but it also said wait one hour between coats, so I figured 5 hours was enough. Thing is, I'm not going to spend loads of money on 3 tins of sealer when everyone is saying it's not going to work, so it didn't really matter anyway.

As I mentioned earlier, if it didn't work, I'm going for the roofing silicone, and I know that'll work. That's just excellent stuff, and had great success with it in the past.