Water under the house !!

[HappyHammer]

The ground floor of our house is on 75% slab and 25% on piles.

During the recent downpour there was about two inches of water sitting under the 25%. The water has since gone away and it is now just damp. I'm worried about this as the other house I owned on piles was always bone dry underneath.

Any opinions on how to solve the problem. I had considered drilling a hole through the outside wall to the space under the house and inserting a tube low enough for the water to escape if this happens again.

Any comments regarding issues the water could cause or otherwise? I'm guessing the piles themselves could become unstable? and / or the water could cause rising damp although I'm pretty sure it wasn't higher than the damp course.

I'm pretty sure I could smell the dampness from inside the house through the carpeted floorbaords although SWMBO couldn't smell it so that might be paranoia.

HH.

[echnidna]

Several options for you to think about

• Cut Off drains around the outside of the house
• Drain the low secion under the house
• Fill the low section with packing sand etc

[RufflyRustic]

I too had water draining under the house until I built up the ground to direct water away from the house. Putting in better drainage in that area when we put in the shed has also stopped the water draining that way.

cheers
Wendy

[HappyHammer]

I think the next step will be to wait until it's dry and then test to see where the water is getting in as there is no obvious entry point. I'll see if I can take some pictures to explain it better.

HH.

[HappyHammer]

OK..............

Pic 1
This is the step to the front door and the start of a concrete gutter that runs across the front of the house. You can see where the last rain deposited dirt.

Pic 2
The concrete drain continuing across the front of the house.

Pic 3
Around the corner the water is basically deposited here and I'm guessing runs down the side of the house.

Pic 4
The side of the house where I'm guessing the water runs.

Pic 5
Entry into the space under the house. As you can see I have previously suspected this as the entry point of the water as wood meets concrete. But I have used a Brick/Concrete silicon sealant here to prevent the water getting in.

Pic 6
A shot under the house where the ground is still damp.

Pic 7
Another shot of under the house.

HH.

[HappyHammer]

Thanks Bob hopefully the pictures will make the problem clearer.

Several options for you to think about

• Cut Off drains around the outside of the house

Can't do this as water is coming from driveway and if I blocked the gutter it would flow back into the garage.

• Drain the low secion under the house

This is what I was thinking regarding the pipe through the outside wall on the side into space under the house

• Fill the low section with packing sand etc

I'm guessing you imagined and open are under the house rather than the story the pictures now tell, so not sure this would help.

HH.

[HappyHammer]

Any opinions on how to solve the problem. I had considered drilling a hole through the outside wall to the space under the house and inserting a tube low enough for the water to escape if this happens again.

Having re-examined the photos I've relaised I won't be able to run a pipe through the wall to drain it as the inside floor level is lower than outside. (Pic5)

HH.

[jow104]

Having re-examined the photos I've relaised I won't be able to run a pipe through the wall to drain it as the inside floor level is lower than outside. (Pic5)

HH.

And I expect that there is your problem?

[HappyHammer]

And I expect that there is your problem?

Do you mean you think the water is coming up through the soil rather than the water getting in?

HH.

[jow104]

Water always will find its own level and unless your home is on a slope and the laying water is not flowing away or downwards it could be your problem.

So either a pump or the inside level needs raising?

[HappyHammer]

It is on a slight slope front to back which might be why it's pooling up against the wall in Pic7 after coming up through the ground?

HH.

[joe greiner]

It is on a slight slope front to back which might be why it's pooling up against the wall in Pic7 after coming up through the ground?

HH.

Exactly. Water from the high side percolates under the footing and enters the understory. As Wendy says, best to intercept the water outside. A berm against the house, with a swale around to the sides will help. You may need to rebuild that part of the driveway to mate with the swale for complete interception. To reduce debris buildup in the swaled driveway (I assume the driveway is paved.), cut or form a slot or two, about 50mm x 50mm, to increase flow velocity in low-volume conditions. This feature is called a "cunette," often seen in sewers, and other open-channel ditches such as the Los Angeles River. And yes, it has the same Latin origin as a similar word.

Joe