How to waterproof water feature?

[TashB]

Hi, 

I have a concrete Buddha Water feature that had pieces cracking and falling off and generally needs a refresh. I fixed the cracks using Bondcrete sealer, bonding and admix to mortar. Now I want to waterproof the basin again. Some of the concrete in the basin is exposed but some still has paint on it. What can I used to effectively waterproof it? Can Crommelins Waterproofing Membrane Sealer be applied over paint and concrete and then the Crommelins Pond Sealer be put over the top? Is that the best way to do it? Any help would be appreciated as I am a total novice!

 

[Jewelleryrescue]

Hi @TashB   nice  project

You  already have the  solution in you hands, well  done  using admix bondcrete for the  top half plus  mortar.

Bond crete mixed  with pure off white cement  this time 3 coats will give you a white water proof seal. 

If you add some bright yellow sand to make a  mortar your familiar with. will give your a more sandstone look and colour,

Cement 1 part ,  yellow sand 1 part   1/2 part bondcrete   add water to make thick syrup as  paint.

I have it in  big pond  now it is solid and non leaking.

Australian Builders 20kg Off White CementI/N: 0037905 12.34

https://www.bunnings.com.au/australian-builders-20kg-off-white-cement_p0037905

Boncrete and cement will make a white cement paint that will bond  very well and water proof very  well.  no extra required.

Crommelins Waterproofing Membrane Sealer is not UV stable and I had it fail in my pond cracking up needing  redoing which  was a lot of hard work.

To assist your use a Mortars brush  (But a regular brush will work  for small area,)

Dunlop 160mm Renderers Brush 

I/N: 0960322

$28

[TashB]

Hi, thanks for the quick response. The bondcrete says on the packaging that it's not intended to be exposed to water, moisture or dampness or to be used as a surface water protector (unless used as admix). So is what you are suggesting creating an admix mortar paint and that will work?

[Jewelleryrescue]

Yes  an admix paint will seal the  concrete walls as it combines  with cement powder and forms a water proof layer.

Cement  on its own is  water proof  at higher strengths  the bond crete binds the cement to the walls better as a  paint .

If you want you can add a secondary sealler and  color  your pond  if you wish  just make sure it says clearly  uv stable if it dont state UV stable then it  probably isnt.  I learnt that the hard  way I used crommelins pond sealer  NON UV only indoor.

For  my  pond I will go  Nu tech  Nu pool coating great colors and rock solid water performance but only comes in  large pails  not  good for your pond size.  sadly  and a little too much for mine  but  enough to  repaint in 10 years.

You  could  get away with acrylic outdoor paint over the bondcrete admix  should last for 10 years any  color you like?

[EricL]

Hello @TashB 

Welcome to the Bunnings Workshop community. It's wonderful to have you join us, and thanks for sharing your question about waterproofing your old fountain.

When using the Crommelin products it's either one or the other but not both. The Crommelin 1L Clear Pond Sealer is great for waterproofing ponds and water features where no joins or internal corners are evident. 

The Crommelin 1L Exterior Grade Brushable Waterproofer is the next step up. It's a synthetic rubber-based membrane, designed to deliver exceptional waterproofing performance in areas subjected to permanent immersion, areas of non-exposed pedestrian traffic or in application under screeds and toppings.

It's permanently flexible to accommodate structural movement and has excellent adhesion to a wide variety of substrates. It has Low VOC and has a fast-drying time. It's suitable for permanent immersion and storage of potable water.

Aside from its difference in features, the Exterior Grade Waterproofer is grey in colour.

Between the two I suggest having a look at the Crommelin 1L Exterior Grade Brushable Waterproofer as it more robust than the clear sealer.

If you have any other questions we can help with, please let us know.

Eric

[TashB]

Hi, I did as you said with the sand, cement, bondcrete admix. I put the final coat on 4 days ago. I filled up the basin yesterday and when I was adding the water it frothed up like it did when I washed the bondcrete out of my paint brushes. This morning there is a surface scum on the water of what I assume is the bondcrete. Does that mean it's not sealed properly? I did about 4-5 coats over 2 weeks. Other than that the fountain looks great! I'm just worried the boncrete admix hasn't sealed the basin properly and will continue to leak out.

  The surface scum

[EricL]

Hello @TashB 

It's possible that the last coat of BondCrete has not fully cured and is mixing with the water. I suggest removing the water and giving the area an extra week to totally dry off before attempting to fill it up with water. Let me call on @Jewelleryrescue to make them aware of your questions.

If you need further assistance, please let me know.

Eric

[Jewelleryrescue]

Hi @TashB 

I am 100% aware of  what you are seeing boncrete and cement make a chemical reaction and bond  well.  My pond also at first ozooed excess unconverted bondcrete as  far as i can tell but stopped in about a  month it also took on a  grayish color too,  But it is holding  water  for 5 years   now 7000 litres plus on  brick works.   I would  be sad to here if your results differed from long term success, I am  sure  it will suit  your  application.

In  this  pond I used to loose 30mm water  a day (Too fast for evaporation)  Now every rain I and I am having to pumping water out as it is being re modeled  in time.

To  fully disclose I also plan on a second cement  paint with a more expensive polymere  because  i  am paraniod about leaks.    An extra strong physical coating like bond crete.  And them over  paint that with  a  blue coloured water pool membraine from Nu tech which is  super  robust again and pretty.

So I am over leaking ponds lol  and i need it 100% uv stable the

Biggest failing  point of many  water proofs outdoors  If it dosnt say  UV safe it probably isnt. 

Great   work  doing 4 to 5  coats that  2 coats more than me this fills me  with convidence yours is a sucess You and I probable added that extra bit of unneeded bondcrete into the ratio, But no  harm  done.

So Probalbly keep  plant out short  term just in case  but bondcrete is potable mix so should not harm anything.