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One corner of our house in our bedroom can get damp and moist when it rains.
Only this corner so far.
At first we thought its happens because the finished ground level of the yard is too high (higher than bedroom floor). But after we took out the soil lowering the ground level, the problem still persists.
Visually we do not see any brick wall cracks.
One mate told us, "even" the ground level was too high, theoretically the interior floor should not be damp and the problem is the vapor barriers of our concrete slab failed.
The problem is , we dont know how we should approach this and from which kind of professionals we should seek help first
We contacted waterproofing companies and they told us that :
May we also suggest that the plumber double check the fall and that the diameter of the drainage pipe is of adequate size. It would be good to have the pl;umber look at the rest of your property as you may need some additonal drainage system put in place.
1) There is only a rainwater drainage downpipe near that corner. No sanitary drainage pipe. And we installed a new downpipe to make sure there wont be water spilling out from the underground pipe.
2) We understand that upgrading the drainage system can help (There is an old AG drainage system alongside the house).
3) We regraded the side aisle of the house to make sure the water can flow away from that corner. But things only improved a little.
Isnt the first thing we need to do is directly addressing the problem : the leaking slab?
We watched youtube and some companies applied the liquid rubber to the sides of the concrete slab, like this:
It seems much more effective and on point? If there are some "hairline" crack around the corner of the slab, put something to seal them seems to make more sense.
So complicated.
https://construemax.com/leaking-slab-foundation/
One useful link we found about this problem.
What are the most affordable way to solve this? Thank you in advance for any advice.
Any experienced members are specialized in this kind of issues? Really love to hear you thought. Thanks
Hi @ivanptr,
As @JDE has mentioned, it is always best to consider different reasons why this dampness might occur. Entry through the concrete slab is just one of the possibilities.
When did you first notice this issue occurring? Has it always been damp in that room, or is this something new?
I know you said this is in the corner of the house, but are there any water pipes or bathrooms adjacent to this area where leaks could be coming from?
Having a downpipe in that corner is a little suspicious and would most likely have something to do with the issue. You mentioned that you installed a new downpipe, but were the pipes checked for cracks or damage at the same time?
If the water is coming from the outside, I suggest your best bet is doing some exploratory excavation. Dig a 120mm wide trench hard up against the wall to a depth of 600mm. You can paint the side of the foundation and lower bricks with Crommelin 4L Exterior Grade Brushable Waterproofer. It would also be good to install Vinidex 100mm x 20m Socked Slotted Draincoil and connect it to the stormwater line or ensure the current agline is functional and not blocked with sediment.
Please let us know if you have any questions.
Mitchell
Thank you for letting us know about different possible causes. When it comes to the roof, we hired the roofer to replace all screws of our metal roof last month. But we just forgot there has been one problem lingering since we moved in - dripping from fascia / soffit when it rains. Not sure if the rainwater can flow back to bedroom?
And yes @MitchellMc , the corner in the bedroom has always been damp since we moved in.
Though the challenge is, all waterproofers/ roofers who service our suburb are fully booked for months.
Is there any ways we could investigate the root cause ourselves?
So, these days have been very hot without a drop of rain, what if we pour water to the different parts of the house to find out the issue ourselves?
Yesterday, we used the watering can to pour 3 litre of water outside the corner:
And after 4 hours , our moisture meter showed the reading increasing from 7% to 18% in the corner of our bedroom.
Could this be enough to come into the conclusion that the concrete slab/ brick wall definitely leads to ingress and need waterproofing?
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Also, about exploratory excavation, we are very confused about the foundation. After we took out 6cm thickness of soil up against the wall, we couldnt dig deeper anymore. Is this the bottom?
Hello @ivanptr
Thank you for the update. In this situation, I suggest doing a process of elimination. I would start with fixing the leak from your fascia. This leak is possibly happening under your roof and is getting scooped by your ceiling. It could also possibly be leaking into your wall cavity causing the damp corner.
Waterproofing the side corner of your house is also another option. Any cause you can eliminate is one less thing to think about. You mentioned that you had your roof serviced. There is a possibility that one of the screws seals has failed. Putting a dab of Selleys 290ml Clear Storm Waterproof Gutter And Roof Sealant on each screw head eliminates this possibility.
I'm afraid this will not be a quick fix, looking for the source of the moisture leak will take time.
If you need further assistance, please let us know.
Eric
@JDE , no sign of plastic membrance so far. Understood 70% of your explanation after some googling.
This house shown in the video:
https://youtu.be/ArqQ_oT1VBg?t=164
which seems to have an similar concrete edge bulging out , like what we are facing here.
And these people dug a trench next to the footer.
Just to make sure our understanding is correct, we drew a picture :
Are we getting this right? 🤔 Please correct us if we misunderstand something
Yes! Process of elimination, a very good idea. We feel like we are making progress:
Brick veneer and footer : better to paint some Crommelin 4L Exterior Grade Brushable Waterproofer sealing the side corner
Roof screw: no need to investigate, just spray Roof Sealant , easy
Fascia: Hire someone to inspect it
Downpipe: ??
About the downpipe, this morning we dug out all the soil surrounding the section and the downpipe might be the "main cause", since the soil are are very moist even without rains for days
If this section really leaks again, then we will be very confused as our plumber replaced this section twice already.
There are 2 reason we could think of:
1) The finished ground level has always been too high so when we grade the ground, it became much lower and the pvc pipe is not buried not deep enough, so when you walk above it, this could dislocate the joint again.
2) The last section of the whole rainwater drainage system which discharge the water to the street has always been "squashed" by rocks. Thats what the plumber told us from the camera inspection. And could this lead to backflow and water pressure causing leaks in other sections?
If this must be solved, then I guess we will bite the bullet $, and ask the plumber to do the work using bobcat or some excavator, dig out the collapsed section buried deep in the slope.
On the other hand, we are tempted to create another route for this downpipe, simply reduce the burden on the existing drainage system. Seems to be much easier and less expensive
Not suggesting you need to do this just a picture to show what I was trying to explain The bulge at the bottom is your footing and you need to dig down beside it
