How to ensure under house doesn't flood again?

I'm sorry to hear you're experiencing issues with this weather @totocol.

A submersible pump sounds like a great solution. Not only will you be able to pump out the current standing water, but if you purchase one with a float switch, it will turn on automatically in the event of flooding and keep the water level below the aircon. However, if the water entering the space exceeds the capacity of the pump, then it will only keep the flooding at bay temporarily.

For our helpful members to provide advice on a permanent solution, we'd likely need to know a bit more about the lay of the land surrounding the house. Generally, you'd start with the lowest point where the flooding occurs and place a stormwater pit there. The water would then be piped outside the wall and ideally connected to an existing stormwater line. If it's purely the wall retaining the water and not due to the lay of the land, you could look at removing a few bricks from a lower course of the wall and replacing them with a Builders Edge 230 x 75mm Galvanised Brick Vent. These will give the water an escape route, and it would hopefully then disperse into the yard.

Please let me know if you have any questions.

Mitchell

https://www.workshop.bunnings.com.au/discussion/comment/18551#Comment_18551

Thanks @MitchellMc
i managed to buy the last pump at my local Bunnings and the water has kept levelled while the rain has continued.

that’s the lower side of the house and it does seem like the water has nowhere else to go once it pools there. There is an absorption pit on one side of the house and and ag pipe on the other side but we’ll definitely need to djj ok some adjustments after the rain ends and things settle a bit to ensure we’re more prepared for future floods.

thanks again

https://www.workshop.bunnings.com.au/discussion/comment/71944#Comment_71944

Hi @MitchellMc

Just wondering a couple of things:

- what type of pvc cement would you need to join 90mm pvc pipes?

- how do you usually attach the vent?

thanks!

https://www.workshop.bunnings.com.au/discussion/comment/99296#Comment_99296

Hi @totocol

I suggest using Protek 125ml Type N Blue Cement Solvent. This is the recommended glue to use on PVC fittings. You'll need some mortar to fix the vent into the brick wall. You can also use Selleys 350g Heavy Duty Liquid Nails, but the mortar gives a much better finish.

Here is a handy step-by-step guide: How to replace a vent in a brick wall

If you need further assistance, please let us know.

Eric

https://www.workshop.bunnings.com.au/discussion/comment/116441#Comment_116441

Thanks @EricL

I finished the stormwater pit today (photos attached) but had a quick question. I’m wanting to add a drain on the other side of the house to divert water away from the house. The driveway was built using a V shape like slope so the water is flowing into the middle of the front yard and getting saturated quite quickly on the one spots I’m trying to create a drain from the end of the driveway in the middle point where the water is being collected and divert it forwards the hedge so not al water go to the same spot. My question is, do EasyDrains cole with a fall so that I can add the drain to follow the same direction of the driveway concrete or will I need to have a different level on the drain to the level on the driveway? I’d prefer it to be ok the same level so it’s more aesthetic.
Thanks!

https://www.workshop.bunnings.com.au/discussion/comment/126273#Comment_126273

Hi @totocol,

I'm a bit unsure whether I follow your question correctly. Could you post an image of the driveway and mark where you intend to place the draincoil?

Easydrain Draincoil can be laid with a fall as long as the fall diverts the water to the intended location.

Mitchell

https://www.workshop.bunnings.com.au/discussion/comment/132826#Comment_132826

See the photo of what I mean of the “V set up”. I just think it would look more aesthetic if aligned with driveway while having a fall underneath but maybe better to set up something like a vortex pit like https://www.bunnings.com.au/product_p0059936?referrer=RetailApp&utm_source=Bunnings&utm_medium=ProductFinder&utm_campaign=BuyThisProductOnline

https://www.workshop.bunnings.com.au/discussion/comment/136870#Comment_136870

That sounds like a good place for a French drain @totocol. Just dig a 100mm wide trench at the end of the driveway, place Draincoil at the bottom directed to the side hedge and backfill the trench with gravel.

The Vortex drain in the middle of the V would also work well.

Mitchell

https://www.workshop.bunnings.com.au/discussion/comment/139635#Comment_139635

Thanks, @MitchellMc

two quick questions:

- would I still add a pit at the end of the V?
- can I still add the grass again on top of the gravel if I put a bit of soil on top of the draincoil?

thanks!

https://www.workshop.bunnings.com.au/discussion/comment/141527#Comment_141527

Hi @totocol

Adding a pit would accelerate the diversion of the water into the drain coil. If you place gravel on top of the drain coil, putting the turf on top of the gravel is no longer an option.

If you need further assistance, please let us know.

Eric

https://www.workshop.bunnings.com.au/discussion/comment/142937#Comment_142937

Thanks @EricL

we added the vortex pit but the grass continued getting really wet and the crowling space on that side is also pooling water after the last bits of rain so wondering about some more long term solutions. The other side of the house with the new stormwater pit did not have issues with the recent rain.

The builder sent a photo of an AG-pipe he added to the side that’s getting really wet and transferring water to the crawling space. My current hypothesis after doing some reading is that we maybe have some issues with negative grading and that we might need to remove the turf and re level the soil to ensure there is a bigger slope moving water towards the hedge and away from the house as well as some more AG pipes perpendicular to the current AG pipe. Does this sound like a good approach?

thanks!

photo below of the ag pipe

https://www.workshop.bunnings.com.au/discussion/comment/143924#Comment_143924

Hello @totocol

This is an excellent approach. If your overall view is that the current slope of the turf is more angled towards your house, I agree with your idea of changing the level of the turf and having it fall towards the front away from the house. Adding extra AG pipes will definitely help with the redirection of water falling towards your property.

If you need further assistance, please let us know.

Eric

https://www.workshop.bunnings.com.au/discussion/comment/144693#Comment_144693

Thanks @EricL

just a quick question. The side of the house that has only a small part of the foundation exposed has the vent very close to the floor so it would be covered if I increase the height of the soil on that side. I’ve found vent covers being used in some overseas websites but I’m trying to find an equivalent here. I’m attaching a photo as an example to see if you can guide me to an equivalent product. They call them vent wells abroad and are made out of galvanised steel

thanks!

https://www.workshop.bunnings.com.au/discussion/comment/145255#Comment_145255

Hi @EricL @MitchellMc just wanted to double check if you had some ideas for the vent well since I’m getting started this weekend. Thanks!

https://www.workshop.bunnings.com.au/discussion/comment/145699#Comment_145699

Apologies for the delay in my reply @totocol.

I haven't seen those vents available. Perhaps you could fashion something similar out of garden edging. You could even brick up a small wall to hold the soil back from the vent. I'd question whether raising the soil and grading it away from the house will do much for water diversion. Unless it's a compacted base or clay, the water will penetrate through it and make its way to the crawlspace or wherever the water table takes it.

We've experienced some rather extreme weather events recently, and unless you have an ongoing problem with regular rainfall, it would be worth considering whether re-grading your lawn is worthwhile. Perhaps install a secondary Agline and see if that assists.

Mitchell

https://www.workshop.bunnings.com.au/discussion/comment/146036#Comment_146036

Thanks @MitchellMc

i will give that a try. Can I confirm that for the agline all I need is to get some socked and slotted draincoils and then cover them with gravel before putting soil and grass back on top?
thanks!

https://www.workshop.bunnings.com.au/discussion/comment/146327#Comment_146327

That's the basic principle @totocol. You should find these step-by-step guides useful: How to install garden drainage and How to fix a muddy lawn.

Mitchell

https://www.workshop.bunnings.com.au/discussion/comment/145699#Comment_145699

Hi @totocol

It's great that you've received excellent advice from @MitchellMc. Unfortunately, I've not seen a vent well product in the store. As suggested by my colleague you could fashion one out of either brick, pavers or aluminium. I've placed an image below to give you some ideas.

The aluminium has been bent using a hammer and timber to take on that particular shape.

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

Eric

totocols water barrier1.jpg

https://www.workshop.bunnings.com.au/discussion/comment/146037#Comment_146037

Thanks again @EricL @MitchellMc

We ended up combining a couple of additional AG pipes with the regrading of the lawn on that side of the house. We still got some water this latest rain but it was much better than last time. We’re going to re grade some of the areas in the crawling space to direct the water towards the stormwater pit we built and I think that should be enough if we get the same rain again. Would a bit of wetness in the crawling space create an ongoing issue? Should we think of adding some fans in the long term? Do you have some guides on how to add those with a DIY approach?

thanks!

Vents covering before regrading

Two additional pipes

https://www.workshop.bunnings.com.au/discussion/comment/146329#Comment_146329

Great work, @totocol!

I think most houses on the east coast have some type of moisture in their crawl space at the moment. It's somewhat unavoidable when the soil surrounding the house becomes saturated. You're doing well with the ventilation bricks, and just the flowing air is enough to dry out residual water. However, it's never great to have a moist environment under a house, and you could certainly look at installing a Bradford White CSR EcoFan Sub Floor Ventilator. For the most effective setup, you should consider the Bradford White CSR EcoFan Sub Floor Ventilator - Twin Pack. You'd set the fans up on opposite sides of the house and have one powered to draw fresh air in and the other to exhaust moist air out. This creates cross-flow through the crawlspace. You wouldn't need to run them all the time, but it could be an excellent way to assist airflow after heavy rains.

Mitchell

https://www.workshop.bunnings.com.au/discussion/comment/146561#Comment_146561

Thanks @MitchellMc

i have purchased the twin pack one and will be installing soon. My only quick question is that I could not find any power point in the subfloor so my idea is to use a heavy duty extension lead to Run it to a power board in the subfloor and to connect it to a power point that is outside and currently used for the water heater and the connect. Given that these are not very demanding equipment, would this be ok or would you recommend to get a proper electrician to add a power point in the sub floor? thanks!

https://www.workshop.bunnings.com.au/discussion/comment/146761#Comment_146761

Hello @totocol

With such critical pieces on your wall, I recommend engaging the services of a registered electrician. They'll put in the proper power points that will keep you and your electrical system safe in case it gets flooded. This would also be the perfect opportunity for you to connect these fans to an automatic switch that you can turn on/off via wifi.

If you need further assistance, please let us know.

Eric

https://www.workshop.bunnings.com.au/discussion/comment/146761#Comment_146761

Hi @totocol,

The D.I.Y.er in me would like to say use an extension cord, but I'd agree with @EricL here. I think it's best to have them hard-wired in or have powerpoints installed next to them. Provided there is some type of WiFi signal down there, you'll be able to use a couple of these Arlec White Grid Connect Smart Plug In Socket With Energy Meter to remotely control the units.

Mitchell

https://www.workshop.bunnings.com.au/discussion/comment/146915#Comment_146915

Thanks @MitchellMc and @EricL

we have now installed the fans and got an electrician helping us with a couple of new power points. Now running the fans a few hours per day using the smart plugs

Thanks again!