Advice needed for drying out after a flood (with photos)

D_Dickenson

I did post this in the flood section but there seems to be very little traffic there so may be here will work better.

For at least 6 months the washing machine was emptying straight under the floor boards instead of to an outlet pipe so we discovered a lake when we lifted them up. The problem has been fixed but water is soaking up through the foundations/walls so there is clearly a lot more to get out. From reading up I think we need a combination of heat/air circulation/dehumidifiers to solve the problem.

I would welcome any advice but especially any of these questions:

1) Does the dehumidifier provide heat as well or should that be from a separate machine/central heating?

2) The property is currently unoccupied so is cold given it is November. Is it worth leaving the central heating on all the time/part time/not at all?

3) How do we get the moisture out from under the floorboards? We have taken the odd one up here and there to allow air circulation - is that enough?

I'm guessing it will take a while to dry everything out so maybe it is wiser to buy rather then rent a dehumidifier. We have seen these 20l/day second hand ones for £200 on ebay. Thinking of getting one or two of them. Any thoughts if they are the right kind?

Doing a bit more reading about humidifiers it seems there are two types - compressor and desiccant. Desiccant used for colder temperatures and compressors when it is warmer. Since it is cold and approaching winter may be desiccant would be more appropriate but all the industrial dehumidifiers from hire firm look like compressor to me.

I'll attach a few photos of the damp in the walls so if anybody could give their opinion if our problem is mild/average/severe it would be helpful. This is my first experience of dealing with damp.

We are in East London. If anyone localish has all the equipment they would like to rent/sell then please get in touch.

Thanks in advance for any advice

Ganga

Hi,D_Dickenson,i used to work for a plant hire company many years ago that hired out dehumidifiers, they were about the size of a wheelie bin,i seen one working once ( as they were electric and i am a mechanical fitter i never worked on them ) how it worked it had a fridge type element inside that froze and made the dampness stick to it then it cycled and warmed up and the water it collected ran out the front from a tube into a bucket or whatever you put under the tube.The one that i saw was working in a building that had just been plastered and it was drying the plaster out prior to decorating.Also what about buying/hireing a small water pump to pump out any water lying under the floor,people like machine mart do a pump for less than £40.00 or you can get one that fits on the end of your electric drill for a lot less. Best of luck with the clean up anyway

Ganga

tlh858

Your questions:
1 - Dehumidifiers do not provide heat.
2 - Heating needs to be on
3 - A couple of floorboards taken up in each of the wet areas should be fine.

Rent or buy the dehumidifier, whichever is cheaper. Compressor type.
You will be looking at using it for several weeks at least, so probably buy (you can also sell it afterwards).
Make sure it has the facility to connect a drain hose rather than just collecting water in a tray, otherwise you will have to return several times a day to empty it.

Close the external doors and windows, leave all internal doors open.
Set heating on 24/7.
Set dehumidifier on 24/7.

If the flood extends to multiple rooms, floorstanding fans could also be used to ensure air is circulated to all areas.

D_Dickenson

Thank you very much indeed. This is extremely helpful.
We will give it a shot and hopefully fix the problem before winter sets in.

Thanks also Ganga. Fortunately the water was all pumped out by the builders and has not returned so I think it is just what soaked into the foundations/walls that is the problem now. The builders threw some sand down there which I guess is soaking up some of it.

Once dried I have been advised to use cat litter under the floorboards to help get rid of or mask the musty odour which is quite overpowering at present.

bluesnake

Get yourself fan heaters.

this explains temperature vs humidity and think they are reasonably priced 20 litre one - im thinking about getting one too
http://blog.meaco.com/2012/03/06/my-dehumidifier-is-bigger-than-your-dehumidifier-no-its-not/

D_Dickenson

When you say fan heaters do you mean the desiccant dehumidifiers? From that link it would seem to me the 8l desiccant performs as well as the 20l compressor and much better when its cold.

Meaco DD8L (desiccant)
10°C/60%rh 7.3L/day
20°C/60%rh 7.4L/day

Meaco 20L (compresor)
10°C/60%rh 2.9L/day
20°C/60%rh 8L/day

My concern is that the only place I have seen recommending the desiccant is the people who make them - Meaco, everyone else says compressor. But they are a much more manageable size than the industrial compressors so it would be easier to drain them continuously down the sink.

bluesnake

You do not need to leave the heating on, but it will dry much more slowly, possibly start to rot and fungus may also take hold if you are really unlucky.

I would avoid desiccant. Would go with a compressor. Desiccants are good for a small room/cupboard and very low temperatures. It often takes many weeks and in bad cases months for the water to be released.

You have to get the internal temperature up for the dehumidifier, and warm air holds more water, so central heating on. Air needs to be moving so evaporation can take place.

Probably a small area under the boards and something like a "Delonghi HTF3033 3 Kilowatt Horizontal Fan Heater" small and flat-ish to get air movement and heat up down there. They can also be pointed at walls too and the hot air possibly will melt plastic..

If the area is too large and wet, start pulling a fair portion of floor board up or put something like this down in a corner of the floor and then in another room. In another room diametrically opposed open up an exit hole the same size as the fan, in effect causing a wind tunnel - joists permitting airflow?.
http://www.ebay.co.uk/itm/INDUSTRIAL-EXTRACTOR-FAN-12-240-V-2100m3-h-/221014256565?pt=UK_Home_Garden_Hearing_Cooling_Air&hash=item337579ebb5

D_Dickenson

bluesnake wrote: »

You do not need to leave the heating on, but it will dry much more slowly, possibly start to rot and fungus may also take hold if you are really unlucky.

Rot and fungus is my big fear. There is already quite a smell which I guess is a sign of something growing

bluesnake wrote: »

You have to get the internal temperature up for the dehumidifier, and warm air holds more water, so central heating on. Air needs to be moving so evaporation can take place.

Probably a small area under the boards and something like a "Delonghi HTF3033 3 Kilowatt Horizontal Fan Heater" small and flat-ish to get air movement and heat up down there. They can also be pointed at walls too and the hot air possibly will melt plastic..

We took up a few boards here and there and have put a couple of small fans at one end blowing directly underneath and it is creating quite a draft coming up where we took boards up on the other side of the room. The musty smell increased dramatically when we did that so it must be a sign that the affected area is now getting some circulation.

The idea of the fan heater pumping heat under the boards sounds good but I am worried that it may be a fire risk? The property is unoccupied so I would not very feel comfortable leaving that on when we are not there.

Do you think there is a big difference between the 20l compressor discussed above (£160 to buy) and a commercial hire like this which is £150 to rent for a week?

bluesnake

I think the more industrial ones will have better air flow due to bigger fans pushing the air forward. Being a cheap git, I'd buy one Meaco asap just to test, and if it works without the filter, would remove it - more air flow. The problem I foresee with the Meaco is that it would be easier to recirculate the air back to itself. If you are happy, by one or two more.

Air tends to pool, so in a building they usually put one in every room, or two in a large room, and leave the doors open.Get those summer room fans out.

Compared to hiring, you could buy 5 Meaco's and still break even in a month providing you sell them after for £80 and still be a few quid in which i think is very realistic.

I would not be surprised if you were still extracting water in 4 weeks time. Make a note on how much water to take out per day per machine. Remember to heat.

The smell could be from the biological washing powder.

Hazel1980

We bought a house a few years back which was in a complete mess and there had been a leak from the washing machine for ages by the looks of it as there were damp floorboards throughout 75% of the downstairs and we actually fell through the kitchen floor as was rotten! We tried drying them out but the smell just would not go so ended up ripping up the entire downstairs floorboards then letting it dry out then replacing the boards with new and taking all the plasterboard off in the kitchen as was damp and replacing. We had the dehumidifier on for weeks but it was just to bad to be salvaged.

D_Dickenson

Hazel1980 wrote: »

We bought a house a few years back which was in a complete mess and there had been a leak from the washing machine for ages by the looks of it as there were damp floorboards throughout 75% of the downstairs and we actually fell through the kitchen floor as was rotten! We tried drying them out but the smell just would not go so ended up ripping up the entire downstairs floorboards then letting it dry out then replacing the boards with new and taking all the plasterboard off in the kitchen as was damp and replacing. We had the dehumidifier on for weeks but it was just to bad to be salvaged.

Not the news I want to hear but thanks anyway.