In my last blog post I discussed my experience in Hebden Bridge and two properties that had been damaged by the flood water that came on Boxing Day after the incessant rain of Christmas Day.
This time I’d like to discuss the process of damage assessment and beginning to dry the building ready for redecoration and rehabitation. We’ll assume here that the house structure hasn’t been damaged – such as foundations being undermined, walls destabilised with water pressure or impact damage from flood borne debris such as vehicles or trees. These all require specific reviews.
We’ll assume there is no flood insurance, so cost is of paramount importance.
Let us further assume that the water has reached 1.5m deep above the ground floor and that you have a cellar.
The first job once the waters have receded is to get the furniture out. This is obvious, but I mention it because it highlights a fundamental point: contamination. The silt that is left over everything is of course full of potentially harmful bacteria from sewerage. But once dried off and cleaned there is no reason why furniture will not be perfectly serviceable again. The issue for most people is where to do this. If you have a friend with a large warm garage, then fantastic, otherwise it may be easier just to get rid and start again. Clearly any furniture that can deeply absorb water – cushioning, for example – should be discarded.
You have to be honest with yourself from the beginning regarding this matter. If you are happy to sanitise everything with some very well diluted bleach, then you can substantially limit your cost outlay, but if you know you’ll just never be happy until everything is replaced, then your plan of action is also clear. A clear and understood plan from the outset brings the quickest results.
Services: Electrics/ Gas / Phone
Electric first. It is dangerous as we all know, but easily managed. Firstly, find out if you have a modern ‘consumer unit’ rather than the old style fuse board. A consumer unit has circuit breakers that are sensitive to any current being lost and will ‘trip’ cutting off that ring main of sockets or lighting or oven supply. Where your power enters the house and just before the meter there should also be a breaker that will do the same, but for the whole supply to the house. If you still have an old style meter and fuse board (very unlikely) then call your electricity shipper and get them changed.
If your meter or consumer unit have been submerged, then they need changing. Your electricity shipper will do the meter (often the breaker will need doing by the Distribution Network Operator who is responsible for the power cables up to your meter – see here.) The meter will be replaced by your shipper – NPower or whoever – free of charge. The consumer unit is your problem and I suggest getting an electrician in for this. ( Try to ensure he is qualified to Part P of the Building Regs).
Become familiar with the small switches on the consumer unit – each will turn off a circuit in your house – so it is possible normally to isolate say all of the sockets on the ground floor while leaving on everything else. What you need to do once turned off (leave it to an electrician if you don’t feel confident) is loosen the face plate of all the affected sockets and switches and let them dry out. Squirt with a little WD40 to help drive out the water and/or if you have patience give them a good long blast with a hair dryer. If you don’t do this, your electrics may continue to work for some time, but corrosion will slowly occur and eventually an electrical short may happen resulting in your consumer unit tripping or worse a fire (although very unlikely).
Gas. If your meter has been submerged, then give the your gas shipper notice, but generally pipework design to keep gas in will keep water out.
Phone line. Assuming your phone works just check all your connection boxes are drained of water and allowed to dry. There are no voltages in the cables that will cause you any harm. Likewise any TV aerial points.
So, the big clean up starts in the cellar.
This is because your ground floor will not dry out until the cellar is also drying. If the water is not draining away, you will need to pump. You could call round your local fire station – they will tell if they have the time and resource available. I wouldn’t advocate calling 999. If they haven’t then you need a pump. These can be small petrol/diesel units or electric. You can hire a submersible electric pump that you just plug in (maybe via a transformer as all equipment on construction sites must be by law 110V. The transformer will be a small additional charge at a hire shop) and place in the water. The delivery hose is generally 2″ diameter flat hose and comes in roll. Make sure it is long enough to reach a suitable discharge point outside – you don’t want to accidentally flood your own house or your neighbours again! I wouldn’t bother with petrol or diesel (the latter normally are heavy and difficult to move around) because the suction hose is normally fairly short and you don’t want the fumes from the exhaust in your house – of the possible spillage of petrol whilst re-fueling.
Keep checking to make sure any silt/mud isn’t clogging the suction and stopping the flow. Of the submersible pumps, the best are ‘puddle’ pumps – these will literally suck a puddle dry. All the others will leave 2 -3″ water unless there is a lower recess in the general floor level to drop the collection point into.
Now the messy work. Buckets, a small spade and a chain gang to collect the silt and transport it outside with the least paddling about in the mess! (oversuit, marigolds, wellies, perhaps even goggles to keep splashes from your eyes. A face mask if you like, but unless it is a proper ‘fit to face’ one, they’re next to useless. Perhaps a little added perfume will dull any pong though) Try to avoid introducing more water to clean things up until right at the end, a little water and a wet-vac will finish the job nicely. Make sure any floor gullies are cleaned out and functional.
Now you are ready to really crack on with the cellar drying out process.
Are the walls just painted masonry or covered with boarding or plasterboard? Remove whatever covers the stone, brickwork or render. (If plastered this will be soft and mushy and will need removing) Next, you need to know what the ground floor is made of. Generally this will be timber joists supporting timber floor boards. These may be then covered in stone flags. Either way, the whole structure will be saturated and prime for wet rot. The floor will dry out from the top surface unless covered by something such as flags or vinyl. The point to note is that just because the top is dry, it doesn’t mean the floor structure is. What you need is a well ventilated cellar. Air movement dries the best. You do NOT want too much HEAT when drying timber as it will dry too fast from one side and warp the wood. I would suggest opening up the structure from below by removing from the cellar ceiling any plasterboard or timber board finish, and any insulation behind (which could well be a hidden soggy sponge) and then hiring a small fan such as this one. Anything to move air across the surface to be dried will work though – even just a stand alone summer cooling fan directed upwards. What you are trying to achieve is to get the air blown across the damp surface to pick up moisture and then move out of the room to be replaced with drier air from outside – so the house needs to be well ventilated above. Keep an eye out for wet rot. Cellars are often damp, so it may have been there before the flood – it takes longer than just a few days to appear. See here for examples. If you find it on your floor joists, the timber will need treating. This is easily done yourself, but they are nasty chemicals, so be sure to properly read the Chemical Safety Data Sheets and wear the recommended PPE.
A word on dehumidifiers. They are great, but only in a sealed environment otherwise you are only removing moisture from the atmosphere outside, not drawing it out of the structure – that means closing all the doors and windows. So if you are constantly opening doors and windows you are wasting electricity on the dehumidifier. I would suggest using them at night and a fan during the day with the windows open or by use of ducting to get as many complete air changes per hour as possible. An old open fire will change the air in a room as many as 5 or 6 times an hour. A modern house with central heating and the windows shut will not even achieve 1 per hour. Many damp problems in modern houses are really condensation on cold surfaces due to insufficient ventilation – not due to damp coming through the walls or floor. Fresh air is the key to dryness! And the same for drying out. Remember, you will only know how often to empty the dehumidifier bucket by watching it!
Your goal is not to keep a room prone to damp from getting worse, but to quickly suck out a lot of moisture from the structure, so it is unlikely a small domestic type dehumidifier will be efficient enough for the task. Here is an example of the size you need. (I have no link with any hire shop business) The cost will be worth it.
OK, so the cellar is drying out, and furniture is gone from the ground floor – it’s time to inspect the flooring.
Stone flags – its worth getting one lifted to see how much wetness/damp there is trapped underneath. This is a tricky call to make as to whether the lot needs lifting. Ultimately, damp and timber do not mix well.
Ceramic tiles – these may well be laid over stone flags, so the problem is the same. Possibly the same for vinyl if it is still well bonded. If it is on timber boards, it will probably have lifted with the water.
Laminate flooring – it has somehow survived (I’d be amazed) it still needs to come up to allow what’s underneath to be inspected/ or dry.
Hard wood flooring – whether this warps badly as it dries has a lot to do with how it is fixed and how it can dry. Generally, timber dries out with less warping if both sides dry evenly, hence the importance of ventilating the underside – and avoiding too much heat on the topside. If it is tongue and groove with secret nailing in the groove, then the board can still ‘belly’ up in the middle as it swells with the absorption of the water. A narrower board (say 4″) will fair better than a wide board of 6-9″. As it thoroughly dries out, watch how much the board settles. It may be that a few light passes with a floor sander will bring the floor back to a satisfactory level finish. The sanding will also serve to remove any surface contamination. DO NOT re-varnish until the boards are nicely dry.
Skirtings – If the skirting board is deep it will be trapping moisture behind it and will most likely warp as the wall fixings will not be sufficient to restrain it. A small 3″ or 4″ skirting board should fine.
Plaster – this is a gypsum based material. Gypsum doesn’t like water. Plasterboard is the same. If plasterboarding has been used to form a fire wall (not normally an issue for domestic dwellings, but could be for a B&B/hotel/hostel), then once wet and dried out, it has generally lost its fire resisting capabilities.
You may be lucky and the plaster may dry out and still remain solid – prod it with something sharp to see. Often as a wall dries it will draw salts to the surface of evaporation and these salts will be hygroscopic – meaning that any dampness in the air will appear on the wall as a damp patch – it is not the wall that is compromised, but the salts in the surface of the wall. Make sure to paint the wall with a sealer before decorating.
Some people may tell you that the plaster needs hacking off anyway to allow the wall beneath to dry. This is a debatable point. If you have a cavity wall, it will dry to the cavity fairly quickly and if it is an old solid stone wall, it will be generally rubble filled, which is free draining. After the wall is nice and dry, you will then soak it putting on the new plaster. It is really the salts you need to be concerned with as they will often show false dampness. If the wall is rendered on the outside, then it will struggle to dry out and then it may be that the inside plaster needs removing to allow the drying process to work efficiently.
If the plaster is soft, then it needs hacking off. Do it yourself and save money – its a simple job. Get an electric breaker with a hammer action. Watch this for how. You can now just find a good plasterer with a good reputation. (it needs blending in with that above the flood line, so it needs to be someone with some skill. Best to use a dado as the break line if possible – you might want to consider introducing one, if you haven’t already got one.)
However – you might want to consider something that will not suffer should the worst happen and the water comes again. There are many companies now that offer some impressive products. An example here. You may still want a finish coat to give the smoothness you’ll want for painting – this is best being a lime based plaster as any future soaking will not affect it.
Final word on your cellar. It is not a cheap solution, but there are products now that can be applied like a render that will waterproof basements. Obviously you need to establish just how the water is getting into your cellar, but if it is through the walls/floor rather than obvious conduit like an backing up drain, then it can be dealt with effectively. Have a look here.
This is a very brief overview of some things to consider, but hopefully it may assist in planning the way forward at a very stressful time.
Best of luck, Site Foreman
OTHER LINKS WORTH REVIEWING:
Guide to preventing flood damage
Contractors guide to flood damage repair (PDF)
Flood damage to traditional buildings (PDF)