Advice Required. Pooled water under house

[Mike N]

Doing some decoration and removed the front room carpet a few weeks ago. Since then, every time it rains we are getting a bit of a smell. Looked under the floor to find pooled water, may be 2 inches, and that is what is causing the smell. Since I noticed on Saturday the water has dropped by about an inch so this made me think it cant be a leak from a pipe or it wouldnt have dropped. The only pipes under the floor are the heating pipes and I have stuck my head down to listen if I can hear a drip. The void under the floor is around 5 feet so I thought that if anything was dripping I would hear something. But no.

Anyone have any ideas if it is connected to the rain, why that might be. The only thing we have done outside is fit a water put to the corner of the house and whilst the downpipe looked like it had dropped a couple of inches, I cant think of anything else.

 

[locoblu]

First thing I`d do is get under the floorboards with a powerful TORCH and try and establish where the water is coming from, It does`nt sound like your central heating pipes to me either as you would be forever topping the system up, it could be a cold water inlet pipe leaking but from what you said it sounds more like rainwater getting in, check your gutters are clear and the flashings etc..... good luck.

 

[Stanley]

I have the same problem, but mine is the rain.

I dug a pit in the earth under the floorboards and sunk one of these in and it works perfectly. With all the rain we have had recently its been on quite alot.

In the summer I am going to get a builder to come and fix the problem properly, I understand its called a french drain.

 

[Citytillidie69]

If you live in an area with a high water table then moisture and standing water under the floor is common and nothing serious to worry about. Just ensure the void is well ventilated ie the air bricks in your outside walls are not blocked or covered.

The smell of damp within the floor void is common ie musty smell. again you probably only noticed this since you've taken up the floor boards and once the carpet goes down again you shouldn't notice it.

If the smell is not of damp but a more, how can i put this....effluent smell, then there could be a possibility of a cracked drain. this will need to be sorted ASAP as it will only get worse and in years to come can cause subsidence as "rushing" water can gradually weaken foundations.

But as I said first, the chances are that the water/moisture under the floor is due to a high water table.

 

[Mike N]

Thanks for that chaps.

I thought it might be normal so I asked the neighbour if I could look under his floor and whilst it looks slightly damp it is not the 2 inches I've got.

It does seem like its connected to the rain and as we are going to get some more rain soon, I will be able to monitor it. Im also going to have another look at his down pipe to see if that has got anything to do with it as it had moved since the water butt was fitted as I can see the where the pipe had been painted by the former owner.

 

[Citytillidie69]

I have the same problem, but mine is the rain.

I dug a pit in the earth under the floorboards and sunk one of these in and it works perfectly. With all the rain we have had recently its been on quite alot.

In the summer I am going to get a builder to come and fix the problem properly, I understand its called a french drain.

Stanley, If I was yourself the first thing I would check would be if you also live in an area with a high water table otherwise your water pump will be on constantly on and the land drain wont make much differnce as this too will be constantly draining (basically pissing in the wind).

Have a look at your outside gullies (at the lowest point around your house) and check the level of standing water in them, this can be a quick indication of water table level (ie the natural level the water settles at) and if that level is above the ground level in the void under your floor boards then thats why you have a damp void. Its nothing to worry about as long as the void is well ventilated.

 

[Citytillidie69]

Thanks for that chaps.

I thought it might be normal so I asked the neighbour if I could look under his floor and whilst it looks slightly damp it is not the 2 inches I've got.

It does seem like its connected to the rain and as we are going to get some more rain soon, I will be able to monitor it. Im also going to have another look at his down pipe to see if that has got anything to do with it as it had moved since the water butt was fitted as I can see the where the pipe had been painted by the former owner.

Mike, just ensure that the formation levels in the void under the floor boards are both the same, because if his is higher then he wont get pooling water.

 

[Stanley]

I have the same problem, but mine is the rain.

I dug a pit in the earth under the floorboards and sunk one of these in and it works perfectly. With all the rain we have had recently its been on quite alot.

In the summer I am going to get a builder to come and fix the problem properly, I understand its called a french drain.

Stanley, If I was yourself the first thing I would check would be if you also live in an area with a high water table otherwise your water pump will be on constantly on and the land drain wont make much differnce as this too will be constantly draining (basically pissing in the wind).

Have a look at your outside gullies (at the lowest point around your house) and check the level of standing water in them, this can be a quick indication of water table level (ie the natural level the water settles at) and if that level is above the ground level in the void under your floor boards then thats why you have a damp void. Its nothing to worry about as long as the void is well ventilated.

I quite often get pooling water outside, esp. after heavy rain. The voids are well ventilated, and it does tend to clear quite quickly after the rain has gone.

I put the pump in more for morale purposes tbh, It is on and off regularly, but the water under there is clearing quicker with the pump. I am also told the reason the table is high is because the ground a foot down is really solid clay, so the water cant get through, good to build on but crap for drainage apparently.

 

[bluemoonchick]

I work in drainage and we come across this a lot. Especially since we're getting so much rain. What you need is dye tests to establish where the water us coming from but instead of paying someone to do that you can use food colouring (used for baking) instead.

Start off with your internal pipework, eg sinks/toilets, pour one of the food colorings in each one and leave water running. Then check the water in the subfloor to see if any colour comes through. If not then try your outside.

Check for cracks/gaps in any patio slabs, brickwork etc, choose a different colour food colouring and use a bucket of water/hosepipe to run water whilst someone else checks the subfloor.

We often find that damp proof courses have failed and ground water is seeping through cracks in patios and walls and getting into subfloor that way.

If you're still not seeing any dye come through you need to do the same checks on any neighbours that are close to your property.

If no luck after that, contact your local waterboard and ask them to come and take samples of the water for testing. They will then be able to establish if its water/drainage. If they get chlorine in the water samples they know its a water service pipe leak. If they get any traces of sewage then its a drainage problem. If no chlorine/sewage then its either surface water drains (e.g. guttering) or its ground water.

 

[Mike N]

Thanks for your help boys. It's just starting to rain now so l'll monitor it.