Water under floorboards

[roadrunner2]

Water under floorboards

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Hi, I have found water under floorboards due to a high water table in my area. I believe the best remedy for this is good under floor ventilation via airbricks.
I have so far put an extra air brick in the front of the house and replaced the other airbrick in front of house with a superior air-flow plastic type. I have an extension at back of house with 3 airbricks plus one airbrick to side of extension.
However, there are no airbricks to side of house (gable end - it is a semi) and I'm not sure of the importance of adding airbricks to this section ? The floorboards and joists seem in good condition at the moment but i've no idea how long the water has been under the house.
Should I add more airbricks and if so do I have to insulate the pipes under the floorboards ?

All replies will be greatly appreciated.

Thanks

Flipper2

 

[churchilldog]

How far below the boards is the water level? This sounds like it could be a rather major problem!

 

[roadrunner2]

Hi Churchilldog,

Thanks for replying,

The water is about 3ft below the floorboards and has actually gone down recently, but it rises with the water table. I think its probably been there since the house was built but cant prove that. The fact that the joists still seem ok 47 years after the house was built was really why I was enquiring whether extra airbricks would help at all. Plus sometimes there is a musty smell in hall which I think must be caused by the water under the floors - could airbricks eliminate this smell ?

 

[cmother1]

If it's water rather than dampness it will take more than airbricks to sort it out.
Assuming it is the water-table rather than a broken pipe 'tanking' is the best solution to the problem. Costs a fortune and will totally disrupt your home.

If it's a detached property you might get away with a French drain but if it's groundwater rather than transient rainwater you're dealing with, I wouldn't gey my hopes up.

 

[churchilldog]

Hi Churchilldog,

Thanks for replying,

The water is about 3ft below the floorboards and has actually gone down recently, but it rises with the water table. I think its probably been there since the house was built but cant prove that. The fact that the joists still seem ok 47 years after the house was built was really why I was enquiring whether extra airbricks would help at all. Plus sometimes there is a musty smell in hall which I think must be caused by the water under the floors - could airbricks eliminate this smell ?

No probs, but i'm not an expert please remember! Just a thought though, water alone doesn't smell "musty", it's only when something has got damp. You need to find out what has got damp and is making the musty smell, then you can act appropriately. Extra airbricks won't really help with standing water.

 

[Deluks]

Insulating pipes is wise anyway, a sump pump might be another useful solution here.

 

[JohnD]

is there a concrete slab under the floor, or bare earth?

is there enough room to clamber about?

what is the subsoil like there - rocky, clay, chalk, sand?

are you on a hill?

semi detached. presume all the neighbours have the same problem?

you're sure it's not clean tapwater or smelly drains water from a leak?

 

[roadrunner2]

Hi all thasnks for replying.

There seems to be some concrete slab in hall way but rest of house seems more like a mixed stone/earth so its difficult to tell. Unfortunately there is no room to clamber about. I dug a hole in garden - soil is very clayey and hole filled with water so pretty certain its the water table.

The house backs onto a park which is at a higher level and apparently contains a couple of natural springs - my area is apparently known for a high water table.

I'm sure the neighbours have the same problem but they are all elderly and dont really seem interested.

The water company have tested the water and said it is groundwater - it is crystal clear (maybe spring water ?) so pretty sure its not from the drains.

Regarding the smell , its not very strong and some people can't smell it, but I've always had a strong sense of smell - it disappears as soon as a window is opened. Its just that I know its there.

I have considered a sump pump but thought that if it is the water table the water would just come straight back ?

 

[churchilldog]

I have considered a sump pump but thought that if it is the water table the water would just come straight back ?

Don't! If it's just groundsoil under the house then pumping the water will also pump sediment leaving a nice big hole for your house to subside into!

 

[Nige F]

A musty smell in the hall and "some" concrete in the floor there too. Just what I had in our new (to us) house. Built 1920`s extended 1980`s, Part of the floor in hall was concreted. A small area of timber had been covered by concrete and had rotted. Only a couple of inches had gone , I dug it out and ventilated the area and put a piece of wooden floor back. Not to panic you because it had been wrong for nearly 30 years, but it was where the smell was coming from Can`t have too much ventilation ,in my opinion.

 

[roadrunner2]

Thanks, some very helpful replies. I appreciate everyones input.