How to stop water ingress under house through external brick wall?

Hi @approachmhn,

It sounds like you'll need a multifaceted approach to resolve this issue. The correct way to do this is to dig a 200mm wide trench along the from of the wall to the depth of the bottom of the brickwork. You then need to waterproof the bricks. Next, lay a socked slotted Draincoil in the bottom of the trench and connect it to your stormwater pipes. Note that you'll need a professional for the connection. You can then backfill the trench with drainage gravel.

Although there are membranes that can withstand hydrostatic pressure, simply painting one on the inside of the wall is unlikely to resolve your issue, as the water will then try to migrate under the bricks. Installing a Draincoil, capturing the water and diverting it elsewhere will be the most likely solution.

Please let me know if you have any questions.

Mitchell

Morning @approachmhn

I was just scrolling, scrolling and then BAM! Saw you pic, I would swear that it was the photo I took ages ago of under my house! lol Same issue, same description. The way I fixed it was to actually remove the concrete path (had to to replace my old stormwater pipes) and when i relayed the path with large pavers I used a gravel base underneath. This plus the stormwater pipes being covered in gravel has mean that I dont get a lot of surface water running up against the single layer brick wall and filtering through the brickwork/mortar to form mini waterfalls! Side path rebuild from recyled pavers

Here are some photos of the leak and the path which was helping teh water seep under the house as the path fell back towrads the wall.

01 04-11-2020.jpg

02 04-11-2020.jpg

04 04-11-2020.jpg

05 04-11-2020.jpg

Removing the water chaneling towards the wall worked well. If you dug out the soil against your wall and installed drainage or left the soil at a lower level that could also solve your problem.

It really came down to removing the ability of the water to run that way more then seal the brick work. I have sealed the brickwork in another section of the house and it also worked nicely. Fixing water ingress issues in garage

Dave

https://www.workshop.bunnings.com.au/discussion/comment/39709#Comment_39709

Thank you very much @MitchellMc and @Dave-1 .

with all the suggestions you have provided, I just need to make sure implement it asap.

hope if rain gives sometime this week or next, I will do this over a weekend.

my storm water pipes are at the other end of the driveway. which means I need to cut concrete to connect.

As a first step, I will just leave the water to filter through gravel and flow across driveway.
If it is too much of water flowing across driveway, what is the best solution without cutting concrete?

EricL

https://www.workshop.bunnings.com.au/discussion/comment/82047#Comment_82047

Hello @approachmhn

Would it be possible for you to post a photo of your driveway? This will give our members chance to assess its layout. We can then offer suggestions how to handle the waterflow without cutting into the concrete.

Eric

https://www.workshop.bunnings.com.au/discussion/comment/105771#Comment_105771

Hi @EricL ,

thank you for your response.

Please find the photo of driveway attached. Driveway towards fence is slightly sloped like may be 3-4 cm.

storm water pipe goes next to fence under the soil. Renewed with pvc pipes. We had to remove all scrubs and small trees next to fence because old clay pipe under was damaged due to roots.

https://www.workshop.bunnings.com.au/discussion/comment/120052#Comment_120052

Evening @approachmhn

Oh man, I know about replacing those old pipes 🙂 wooooo lots of effort involved.

As to cutting the concrete, I can see a join line across the driveway. Id use the low side as an edge and cut the high side of it in a straight line across the driveway. I was lucky as my carpenter mate who was use to using a concrete cutting blade/saw did it for me (he also had the saw 🙂 ) I paid him even tho he said nah. By chance, he says on purpose (did not see him measure the distance or the pavers lol ) he cut a beautiful line the perfect distance for pavers to be laid across the width. If you are unsure Id actually hit up a builder to do it as you want it to look nice. When the pipe is laid you can either fill to a little overthe pipe with gravel and reconcrete or pave as I did (if you are going to pave you will need to make sure you have enough support aroundthe pipe for a car to sit on the pavers)

Dave

https://www.workshop.bunnings.com.au/discussion/comment/120052#Comment_120052

Hi @approachmhn,

I'm unsure how you'll allow the water to flow across the driveway. To install the drain coil and drainage gravel, you'll need to dig down to the bottom of the wall. Your drain coil will then be much lower than the level of the driveway, so I can't see the water flowing across it.

Drainage plumbers will have access to machine that can't dig a hole and run the pipe under the driveway without cutting through it.

Mitchell

https://www.workshop.bunnings.com.au/discussion/comment/128776#Comment_128776

@MitchellMc I understand now.

can I put a concrete slab next to the wall. May be a metre width.

will that stop water ingress through brick?

https://www.workshop.bunnings.com.au/discussion/comment/134314#Comment_134314

If the water comes only from the surface, that might work @approachmhn. However, the moisture is likely also coming from beneath the soil and a concrete slab on the surface likely wouldn't resolve that issue. It could help, though.

Mitchell

https://www.workshop.bunnings.com.au/discussion/comment/137865#Comment_137865

Thanks @MitchellMc.

will check with drainage plumber as suggested. And then will do the drain coil and gravel myself.

will update here.

https://www.workshop.bunnings.com.au/discussion/comment/140274#Comment_140274

Hi,

I did seal the wall with plastic throughout as in pic attached. And when it rained I noticed there is no water ingress or pooling on the other side of the wall.

Does that mean can I put concrete slab next to wall so that water flows away?

So I can avoid Agri drain and cutting through driveway.

Appreciate your response. Thanks

EricL

https://www.workshop.bunnings.com.au/discussion/comment/142033#Comment_142033

Hello @approachmhn

I understand that it feels like the plastic has deterred the flow of water towards your wall, but I believe that this is a stop gap measure. Eventually as the water flows to your garden and travels into the soil its natural inclination is to flow towards the lowest point and in this case it's your brick wall. It will travel beneath the slab and then meet up with your brick wall and you'll have the same issue again. I propose acting on the suggestions made earlier and that is to seal the wall and install the agi-pipe to provide maximum diversion to any incoming water that's headed towards your brick wall.

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

Eric

https://www.workshop.bunnings.com.au/discussion/comment/143287#Comment_143287

Afternoon @approachmhn

I agree 100% with @EricL on this, subsurface water will always keep on traveling, putting something in place to handle it even tho it cant be seen is the wisest option. If you spend a bunch of $$$$ on concreting without prepping your area it may come back to haunt you.

Dave

https://www.workshop.bunnings.com.au/discussion/comment/144211#Comment_144211

Thank you @EricL and @Dave-1 .

i will start with sealing the wall and the agi pipe as suggested. Will update as I progress

https://www.workshop.bunnings.com.au/discussion/comment/39707#Comment_39707

@MitchellMc @Got a question regarding painting.

Do I need to paint on both sides of the wall to waterproof?

or just outside wall after digging a trench is enough?

TIA

https://www.workshop.bunnings.com.au/discussion/comment/84635#Comment_84635

The most important part is on the outside of the wall, @approachmhn. However, it wouldn't hurt if you also painted the inside.

Mitchell

https://www.workshop.bunnings.com.au/discussion/comment/137865#Comment_137865

Hi @MitchellMc ,

i dug a trench along the wall yesterday I.e around 10 cm below the bricks where concrete slab is seen.

it rained overnight and I could see no water ingress under the house.

Standing water in the trench remained there for the whole day and there was no water ingress under house.

Looks like the ingress was through bricks. I saw small roots in the brick work at few places which I removed as much as possible.

Should I render the bricks and then waterproof or simply waterproof so that will take care water ingress issue?

Also, for Ag pipe along the wall, should I cover the top with dirt or just gravel ?

I am planning to lay pavers on top along the wall. Is that ok?

My plan is if I lay the pavers on top which slope towards driveway, and there will be less water going towards ag pipe I.e under pavers. So, instead of cutting concrete to connect ag pipe to storm water pipe, I can just dig trench around 2 -3 metres away from wall and leave it to soak to the ground. Will that work?

TIA.

Jason

https://www.workshop.bunnings.com.au/discussion/comment/140503#Comment_140503

Hi @approachmhn,

Great to see you are making progress.

Please note that Mitch is taking a well-earned break at the moment but will be back after Christmas.

Jason

https://www.workshop.bunnings.com.au/discussion/comment/140503#Comment_140503

Afternoon @approachmhn

Waterproofing Will help the water from traveling through the bricks, I use to think bricks were solid and the mortar was waterproof... yeah not so lol I had water entering my garage along fine cracks within the bottom courses of brickwork and sealed them and teh problem was resolved.

Fixing water ingress issues in garage See last step in particular.

Now the second part of your question

"Also, for Ag pipe along the wall, should I cover the top with dirt or just gravel ? I am planning to lay pavers on top along the wall. Is that ok?

Depends on how and where you take your ag pipe. The pavers will still allow water to soak through, See that link I posted. So either way I would go gravel above your ag pipe more so then soil at least from the area of picking up the excess water. If you head downhill to let the water soak in to the surrouinding soil I would try and figure how much water you expect to fill your ag pipe, the length and also the knowledge if it rains then teh ground will be wet as well. Id probarlly suggest a longer run and maybe end up with some back and fourth of teh pipe or spiral and a garden bed on top to help soak up the water? (An inspection point at either end might be handy to flush the pipe out as well)

I used the ag pipe, gravel on top into a stormwater pipe and that area has remained dry even in downpours.

Dave

https://www.workshop.bunnings.com.au/discussion/comment/142189#Comment_142189

Thank you @Dave-1 .

I don’t want to say how many times i refer to Fixing water ingress issues in garage for the work i am doing around my home. Cant thank you enough for that 🙏🏻.

I see you have used https://www.bunnings.com.au/gripset-betta-1l-waterproofing-membrane-bitumen-rubber_p0960165 for waterproofing.
May I know if I need to wait till brick wall is completely dry to paint this? Or a little moisture is fine?

I will do as you suggested for agi pipe I.e gravel till the top. And then some pavers on top to move as much water as possible towards driveway along the slope.

Last time when I renewed storm water pipe, I saw there was an unconnected pipe. I believe that pipe is running under the concrete driveway. Need to start investigating from the kerb side. If I find that, it will be easier to connect the agi pipe to storm water.

So, for now I will just leave the agi pipe soak into ground around 3 metres away from wall.

i will let you know as I progress.

thanks.

https://www.workshop.bunnings.com.au/discussion/comment/143385#Comment_143385

Morning @approachmhn

😀 hahahha you made me smile! Thank you for the compliment 🙂

You will need to wait for the brickwork to be completly dry before using the bitumen paint, and it will stick to everything and I mean everything so be careful using it. It will clag the paintbrush like crazy. I can remember getting frustrated as I felt like I was rushing to get it on the surface before my paintbrush wouldnt work any more 🙂 Maybe have a back up paintbrush handy. Oh and a cleaner for your hands 🙂

You could always push your hose up from the kerb stormwater pipe and see the distance it goes? you might be lucky and not get it caught on breakages or blockages. Twist the hose itself if you feel it getting jammed. Much like you would with the wire clearer for pipes you can get from bunnings.

Looking forward to seeinghow you go 🙂

Dave

https://www.workshop.bunnings.com.au/discussion/comment/144290#Comment_144290

Thank you @Dave-1 .

Good suggestions. That’s less stress.

May I please know how to check if bricks are completely dry?

Also, how long should I wait till I fill gravel back in the trench?

https://www.workshop.bunnings.com.au/discussion/comment/144945#Comment_144945

Afternoon @approachmhn

Touch, just place your palm against the brick and if it feels damp then its a nope, Maybe wait until the sun is up for a couple of hours and check then?

You really dont need to wait to fill the gravel back in the trench, if you are refering to waiting for the bitumen to dry I would look at the container it comes in as I cant remember off the top of my head. I waited until the next day before I put gravel against it tho.

Dave

https://www.workshop.bunnings.com.au/discussion/comment/145465#Comment_145465

Thanks @Dave-1 .

May I know gravel you used. Is it 20-40 mm normal one or like scoria?

https://www.workshop.bunnings.com.au/discussion/comment/145869#Comment_145869

Afternoon @approachmhn

I used 8mm gravel. you can order through bunnings as a bulk bag or there are 10kg bags I think available as well. The bulk order is cheaper tho. I had "estimated" the quantity of gravel I needed (yeah over confident and should have asked the gravel guys lol) and end up with pretty much three times what I needed. Good side I used it under my pavers and it has really worked for me.

The Bunnings bulk order uses a local sand and soil place. The price was about the same.

Dave

https://www.workshop.bunnings.com.au/discussion/comment/146184#Comment_146184

Thank you for all the details. @Dave-1.

one more question. I got the Ag pipe you mentioned in your post.

Slotted and Sleeved 100mm Ag-Pipe.

I need to put an end cap on one side. If not dirt might get inside the pipe.

can you please suggest any options?

could not get much info at my local bunnings, concerned person was on leave today. Also, I could not find anything that works.

Hope I don’t have more questions 😊

EricL

https://www.workshop.bunnings.com.au/discussion/comment/146451#Comment_146451

Hi @approachmhn

I suggest pulling the sock forward and folding over the front of the agi pipe. You can then secure it using duct/cloth tape, once you bury it the soil will keep the sock in place. Please make sure not to fold or pinch the front of the agi pipe.

If you need further assistance, please let us know.

Eric

https://www.workshop.bunnings.com.au/discussion/comment/146451#Comment_146451

Evening @approachmhn

🙂 never too many questions, when you dont ask questions, thats the point of when you stop learning!

So a couple of ways come to mind.

This one allows you to install an inspection grate or cap depending. That way you can flush out the pipe if ut appears blocked.

Holman 100mm PVC DWV Finishing Collar Grate with a bit of a U bend at the end so the cap/grate is level in your yard. The pipe is very flexible and the collar will fit over the end.

Second way and is how I did my drain.

Everhard 1m EasyDRAIN Polymer Grate And Channel plus Everhard EasyDRAIN End Cap on the end of the corrorgated ag pipe. So you could cut the drain in half (there are end caps to fill the end to stop dirt coming in) and top side you have the one half, then pipe down to the end of your trench and then bring up the pipe to ground level and into the grate. It would provide an exit for excess water as well as access points if needed.

Third way is to use a couple of pits, top and bottom to do the same thing (probarlly look tidiest this way 🙂

Everhard EasyDRAIN Polymer Rainwater Pit Case You can get a metal grill or a plastic grill for these pits. You just need a large holesaw to cut a nice hole in the side is all. This would be my favoured option, second favorite option would be the first suggestion 🙂

Just re-read your question and the Everhard Easydrain End cap would do the job on its own I would say. (really didnt need to offer all three lol but no way am I deleting them now 🙂

Dave

https://www.workshop.bunnings.com.au/discussion/comment/146663#Comment_146663

Evening @approachmhn

hahahahah Go with @EricL 's suggestion... So much better. Shaking my head at my over engineered answers 🙂

Dave