Water under floorboards- Help Please!

FLINT

Hi all having noticed a bit of damp ingress along a couple of floorboards at the bottom of my stairs last night I decided to lift up the hatch to take a look under the floor. To my horror I saw approximately 1 1/2 inches of water covering the whole of the groundfloor, my initial thought was that I have a leak from new central heating pipes that were fitted last week however I could see all the joints and there was no sign of any leak.The only other source I can think of were this water has come from is a rainwater gully at the front of my house that collects the water from both my roof and the adjoining house. If this were either blocked or more likely cracked would the volume of water i mentioned be able to get under my floor?I have a friend who works for a tool hire company so have a pump to get rid of the standing water tonight but obviously I need to solve this problem.Any thoughts would be greatly appreciated. Also would my buildings insurance cover any cost to rectify the problem?

diable

It could be the mains leaking, turn off the mains water and see what happens, you will need work out where the leak is coming from first and check your insurance policy to see if you are covered.

FLINT

Hi there thanks for the reply, I will try to turn off the mains tonight then pump out the water. My reasons for saying it could be the rainwater gully is that this water seems to have appeared within the last couple of days after it has rained quite heavily.

iamcornholio

Its quite common for there to be some standing water under suspended timber floors, and this should soak away naturally or evaporate away via ventiltion from air bricks

Have you checked the floor void at other times in the past, or is this the first time you have looked under the floor in winter time?

Have you had lots of rain recently?

If there is nothing obvious, you need to monitor the void. If the gully is leaking you may well see rapid water rise just after rain, and it may eminate from a point near the gully. The amount of water may be generally the same no matter how much rain has occured

If it is natural ground water, then the void may fill up several hours after rain, and will do so evenly and rise very slowly or not at all depending on the amount of rain

David_Aldred

Hi,
Many properties have standing water beneath the suspended timber ground floors due to local high water tables. Things you need to establish are:
Is this actually ground water or is it from some other source.

If it is groundwater is it transient or constant.

If not groundwater is it from a leak and if so is that leakage from your property or an adjoining property and what type of leak is it ? For example mains water or grey water or foul water.

If it is leakage you may be insured to cover the repairs and consequences depending upon your insurance policy and also be mindful that such leakage may impact upon adjoining properties who will need to be notified.

A major concern with water under suspended timber floors is whether there is adeqaute sub floor ventilation (ventilation beneath the floor) to remove that moisture laden air before it is taken up by the timber floor, brickwork above the dpc, low level plaster and jionery in contact with the floor. If there is not enough draught across the void beneath the floor to achieve this then dampness and decay will result with the potential for dry rot as well as wet rot plus an increased risk of wood boring insect attack from those insects which prefer damp decaying timber upon which to feed.

Also this water and moisture laden air can effect services within the sub floor void making it dangerous to enter and increase the relative humidity such that the house becomes at greater risk of condensation / associated mould growth.

First things therefore are to check your insurance policy for what is and is not covered, identify what type of water this is and ensure in any case that sub floor ventilation is adequate to prevent decay. Ask neighbours to see if they have water under their floors, dye test the drains, check for pressure drops on sealed system boilers, have somebody competant check services and ensure they are safe, are all places to start.

The local Water Company may assist with analysis of the water as may independent laboratories such as www.ukanalytical.com Hope this helps kindest regards, David Aldred Independent damp and timber surveyor.

FLINT

Many thanks for the replies guys, I have checked a few things last night, firstly the water is still there ( hahaha), I have looked under the floor quite often over the past few years because we are prone to a little bit of damp on the floorboards, coincidentelly right next to where the rain drain gully is. The void is never bone dry and I wouldn't expect it to be but I have never seen standing water before. I have checked there are no leaks from the central heating, my dishwasher and washing machine are not leaking and my main water pipe goe under my driveway entering the house to the side into a downstairs cloakroom.The rain gully drains into a manhole which I lifted last night and the put the hose into the gully, looking into the manhole I could see it was running freely, so then I put the hosepipe onto the driveway thinking it may be seeping through that way, nothing doing.Whilst looking at the drain hopper top (old clay type) I noticed that there was a gap of some 2 inches between the bottom of that and the actually pipework into the ground. I am now thinking that due to the recent heavy rain the gully may not have been able to cope and it has been overspilling behind and so finding a way into my void. Does this sound viable? I have spoken to my insurers who were not helpfull at all just telling me to ask a builder to diagnose the problem then call them back.

angelavdavis

FLINT wrote: »

Whilst looking at the drain hopper top (old clay type) I noticed that there was a gap of some 2 inches between the bottom of that and the actually pipework into the ground. I am now thinking that due to the recent heavy rain the gully may not have been able to cope and it has been overspilling behind and so finding a way into my void. Does this sound viable? I have spoken to my insurers who were not helpfull at all just telling me to ask a builder to diagnose the problem then call them back.

Is it worth dyeing some water with food dye and pouring it through the gap to see?