Flood Protection
Flood Protection Tips
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Flood Protection - Doors

The most challenging part in preventing water from leaking into your house is the sealing of your doors. The reasons are obvious. The door is a moving part and therefore a leaking source by nature. Once sealed it cannot be used until the flood is below your doorsteps. It is technical possible to install a perfectly sealing door in your house. I am not aware of any manufacturer offering such doors at acceptable costs. Get in contact with me should you plan to design one by yourself. I will send you some helpful information.

When you open your door you will find some kind of rubber band on the inside of the doorframe. It will cover both sides and the top, sometimes the floor too. Do not think this will keep the water out. It is not designed for this task and will not withstand the smallest water pressure. And should your door open to the inside you then better keep the water pump handy. The pressure at the water-covered surface of your door will constantly try to push your door open, thereby decreasing the pressure of the door itself against the rubber band. Not to mention that your door might deform slightly when kept wet for some time.

A good advice is always to be prepared for the worst. Your door knee-deep in the water and having water leaking through, there is really not much you can do to correct the problem (besides strategically placing all your towels around your door and the hope it is over soon).

Always make sure you lock the door you just sealed off as a safeguard against accidental opening, which will definitely destroy your work. Leave the key in the lock. You might be forced to get out fast because of a fire or other emergency. Never imprison yourself. You also may prepare an emergency exit (do not forget to place a ladder near the window if it is located on an upper level!).

There are many ways to seal off a door. Just remember that everything should be done before the water reaches your door and all preparations have to take place at the outside. It is one of the most important basics of flood protection: have the water pressure pushing your protection into place, never away from it. The higher the water level, the higher the water pressure, the stronger the sealing.

How to protect your door from leaking depends foremost on the basic type. You might find 3 different types of doors at your house:

  • Regular doors (like your front door)
  • Sliding doors (usually glass doors to access your porch, yard, etc.,)
  • Garage doors
Since all types of doors are working in different ways they have to be protected differently.

Regular doors

Your house might have more than one exit. Take a good look at all doors and decide which one you will use as main entrance during a flood. Base your choice on altitude, accessibility, and surrounding conditions. For example, it is not a good idea to choose the higher leveled back door leading into your tomato garden when you have to climb fences and go through rose bushes to get on the road. The best solution is to find a door where most likely no water will reach. I will come back to this point when describing how to fight a flood and how to prepare your yard.

Donít wait until a flood is actually reaching your house. To be prepared means to know exactly what to do if necessary. All crucial decisions should be already made, leaving you with just follow your own protection plan. You just go out, prepare your main flood exit (or entrance) and seal of all other doors. Quick, thought through and effective.

The first step is to make sure that the doorframe is fitted in tightly. Should you find any gaps you have to close them with an appropriate filler. Next, inspect the rubber band inside the doorframe. Make sure the band is in good condition and not damaged. If you have any doubt then replace it. You get it relatively cheap from your hardware store. Do not try to fix it, you will not save much. It is even a good idea to keep a certain length of that rubber band in storage. You may use it for many task during a flood.

You can test the effectively of your door sealing very easy on a windy day. Close all windows and your door and light up a candle on the inside. Move the candle around the gap between door and frame. If the flame stays calm, your sealing is ok. Mark all locations where the flame starts flickering and check the rubber band in this area. I do not have to mention that the lower parts of your door are the most important. Once the water reaches the top of your door you definitely will have much more serious problems. Don't forget: get out and in safety as long as you can.

I will give you now some examples how to seal off a door completely. A door is usually strong enough to withstand normal water pressure without cracking apart. But should your door contain larger glass parts you would be good advised to treat it like a window as described earlier. Under a certain pressure glass will not just crack, it will explode without any warning signs. And you would not believe what a little swimming stick can do to a pressurized window. Better prepare a plywood sheet larger than your door, cover it with foil, attach a rubber hose and screw it tightly on your doorframe. Make sure the rubber hose always touches the doorframe, not the door.

The most difficult part at sealing off a door is at the bottom. This picture here shows the two basic types of doorframes as they may installed at your house. In this example the doors are opening to the inside (to the left). The green area represents the floor on the outside.

The lower doorframe on the left part of the picture is on top of the floor and easy accessible. The rubber hose of the protection sheet can push against the outside of the lower frame and, when properly attached, is sealing off the door completely and highly effective.

In the right picture the doorframe is fitted into the floor and leveled to match the surface around it. This creates a problem: it is nothing there to push your sheet against. The rubber sealing (marked gray in the picture) will not prevent the water from leaking through. As the flood level raises, the water pressure increases. Sooner or later water will force its way inside. Therefore you should be especially careful when protecting such doors. The best solution would be to prevent the water from reaching your door. When I show how to battle a flood I will come back to this.

If there is enough space between your door and the end of the outer frame you could fit a plank on the bottom against which to screw your sheet. This way you will create an accessible lower frame of your door. The plank must fit in tightly and will have to be screwed at the bottom. You also need to give your plank some kind of sealing before put it in place. A good and cheap way to do this is by using an old rubber tube from a bicycle tire. Cutting the tube open will create a useful rubber band, which can be used for many tasks.

Cut the rubber to fit the width of your plank. Staple it at the bottom of your plank. Without stretching the rubber, fold it tight over both sides and staple it on the top. Staple the sides also to prevent sliding off during installation. Then drill holes from the top to the bottom for the screws.

In the picture shown here brown represents the plank, black the rubber, and the "U" the staples.

To make this sealing work you have to be as precise as possible. It must sit very tight on the bottom between the side frames of your door. Force it carefully down with a hammer and screw it tight to the bottom. Then fit your plywood sheet against it and secure it tightly all around.

If, based on your location, there is no danger of high flood levels you might consider just enforcing your door seal. It is essential that the rubber sealing of your doorframe is in perfect condition and your door is adjusted properly. Before your door lock snaps in you should be able to feel a slight resistance. All you need is a rubber band created from a bicycle tire. Completely open your door and place the rubber band over the door sealing on the bottom. Use some tape to hold it in position. On both sides your rubber band must lead some distance upwards, also covering the sealing. When taped in place, close the door and squeeze the band in. The resistance of your door just before falling into the lock should be clearly stronger. Otherwise double the thickness of the rubber by folding the band before placing it over the door sealing. It is an easy and fast way to strengthen your sealing. But be warned: if the water level exceeds your rubber band on the sides you will have leakage!

Another fast way to seal off your door is covering it with a plastic foil. You will need a good waterproof foil like probably used in your wall for insulation purposes. It should be about 20 cm (8 in.) wider than your door and covering your door at least half in height. It is essential that it will lean closely on your door when attached. To hold it in place you will need some planks (2 by 2 in. is good). Cut one plank so it fits in the doorframe on the bottom, and two planks for the sides in a length of your choice. Drill a few holes in the planks for the screws. Lean your foil on the door and tape it in place on the top. Make sure your foil exceeds on the bottom by about 10 cm (4 in.). Now fit the plank in the doorframe and push it carefully to the bottom, as close as possible to the door. Screw it tight on the doorframe. Do the same on both sides. You can increase the effectivity by attaching a rubber band on the doorframe before putting on the foil. When the planks are attached they will squeeze the foil on the rubber, providing a highly effective seal. Label your foil for the right door, roll-in the planks and attach a bag with the screws. Store it for the next flood.

The following picture shows how this door protection should look like.

These examples should give you some ideas how to seal off your doors. There are too many different kind of doors to describe them all. But knowing the principles you should be able to find the best way for every door.
Always test your protection before storing it away. It can be done very easily. Just install the door protection and give it a good shower with your garden hose. Point especially at the sealing area. After that, just open the door with the protection still installed and check out which area is wet or where may be leaks.

It is not always necessary to cover up the complete door. You will know best up to which height the water level is expected to rise. In most cases covering the lower half of your door should be enough.

Never block off your main entrance as long as somebody is staying in the house. Rather look for ways to keep the water away from the door (see chapter about how to protect your yard). If then the flood reaches a critical level you should have time enough to seal off that door before moving away to a saver place.

Sliding doors

Sliding doors are used to access the porch or the back yard. Usually it is a unit of a glass door fitted in a metal frame and a door-sized window beside it. The unit itself has a surrounding metal frame. A sliding door can be a very nice and enjoyable thing, as long as floodwater does not reach it. Then you have a problem! The reasons are obvious. As its name tells the door function is to slide open. The easier it slides the more it will leak. It's that simple! The material is glass, which doesn't like much pressure. This makes it dangerous. When it cracks it will explode into your house leaving a big hole for the water to flow in. Imagine a flood level of 1-meter (3 feet) at that door when it cracks. It will create an internal flashflood in your house so powerful that it will knock you off your feet and move your furniture, all of it! The danger is even greater if the flood is slightly flowing towards that door because it increases the pressure, and all kind of staff is floating around and could hit the glass.

All this leaves you with just one option: treat your sliding doors the same way as you treat your windows. Of course, most sliding doors, especially those leading to a porch, are in a fairly save altitude to the surroundings. It may even not be necessary to protect them at all. But it is always better to be prepared than sorry. You also may just shield the door unit with sandbags.

Most sliding door units are wide and require a large sheet of plywood to cover them. Look in the chapter about protecting your windows for some ideas how to prepare it. The rubber sealing has to contact the wall around the door, never the doorframe or the glass. You should also screw it very tight on the wall and make sure the rubber hose is squeezed everywhere evenly.

If you don't have an even surface around the door unit you should create one. Take some boards or planks and create a decorative frame around the door. A little bit paint and nobody will guess your intention. Using your creativity you always can combine flood preparation with decoration.

If the bottom of your door unit has not enough accessible frame to press your sheet against then you will need to prepare one. See the section about protecting regular doors for some ideas on how to do it.

Do not use just plastic foil to shield the glass door. It does not take the water pressure off the glass and will rip apart when the glass breaks.

Garage doors

We all love our garages with the wide remote controlled doors. And the side entry leading directly into the house. But during a flood we will suffer for this convenience. The problems with garage doors are obvious. The main structure of the door is metal, closing into a metal frame. It is just metal on metal without any resistance for the water. Minor mishaps with your car might have slightly bent the frame and could even increase the gap between door and frame. In most cases the bottom has no frame at all. This means that in case of a flood it doesn't make a difference if your garage door is closed or wide open. The result will stay the same: water everywhere! The easiest way to deal with that is just let the nature have it. Install some shelves and store your valuables in a saver altitude. But if your garage and the floor of your house are on the same level and are just separated by a back door you will need to do something to protect your house from being flooded. More important, if your garage is below the ground level (as part of your basement, for example) it has to be the first thing that needs your attention. In this section I will show you some examples how to prepare and protect those two types of garages.

Ground level garages

The large door of a garage makes it difficult and relative expensive to give it a reliable protection. Adding to the problem is the fact that the ground near the door is usually paved and not always perfectly even. If you use the same line over the years to drive into your garage the pavement could have gave in a little bit. It is not always visible with the naked eye.
Since first priority should be to prevent water from leaking in your living area you will have two options what to do: try to seal of your garage door or concentrate on the back door to your house allowing the garage itself to being flooded. Which way is the best for your property is up to you to decide.

Protecting the back door is easier and cheaper. Just seal it off like a regular door as described in the chapter about doors. Install the protection at the garage side of this door and don't use it any more until it is safe to do so.
If you want to protect the garage itself you will need some materials you should get before a flood is happening. You will need a good waterproof foil. It should be at least 2 meter (6 ft.) wider than your garage door.

To be continued.......

Basement-level garages

To be continued.......