Basement under water – preventive measures and first important steps
As beautiful as summer is, it also brings plenty of storms with it. And heavy downpours have a dangerous consequence in the long run: floods. Above a certain amount of water, the soil can no longer absorb water, it continues to flow into rivers and lakes, which are then overcrowded at some point and overflow. A basement full of water is just one of the terrible consequences of floods and floods. But if you have exactly the problem, you shouldn’t despair and do things that are rash and hasty. Because these could cause just as much damage as acting too late and even be life-threatening. So what should you do if your basement is under water? And what are suitable preventive measures? We’ll explain it to you!
Preventing a basement from underwater
The easiest way to protect your home from flooding is when you are still in the planning phase. Protective measures are not only recommended in flood risk areas. Floods could also occur in other regions for various reasons. Therefore, you should find out about any structural measures from your construction company. Those that prevent a basement from being underwater and that can still be planned during the construction phase, depending on requirements and terrain, are:
Measures to be taken before the start of construction
- Waterproofing, barrier plaster and drainage systems, which prevent water from entering through the walls.
- Black and white tubs
- Determination of the design water level, in other words, the highest water level that has ever been measured at the location of the building to be built. The planner determines this.
- The House build elevated.
- Backflow flaps in the pipes prevent water from the overcrowded sewer system from entering the house’s water pipes (usually even mandatory).
- You should get the Do not seal outside areas too much, because the more asphalt, concrete or other sealing materials spread across the property, the less water the soil can absorb. Therefore, use materials that can absorb water (gravel or special paving stones) and leave enough green space.
What you can retrofit with to avoid an underwater cellar
- Backflow flaps for the pipes can be retrofitted.
- Steps in front of doors can protect ground-level buildings from the ingress of floods. A basement door in particular should be equipped with such a step. So that it really protects against your basement being under water, a height of 10 to 15 centimeters is recommended.
- Rain barrels or water reservoirs can collect excess rainwater and thus relieve the soil by gradually releasing the water. They can be built into the ground and are not visible. The collected rainwater will also be used for watering in the hot summer months.
- Speed bumps are very practical for houses that are in a depression or slope, because they prevent the water from reaching the property. But keep in mind that such an earth dam also requires a building permit.
- Upstands are built around basement windows to prevent water from penetrating through these weak spots. Even Pressurized watertight basement windows are possible.
- Closures for building openings can prevent a basement from being flooded.
- Mobile protective elements can protect the house from flooding if they are installed in a timely manner. Such are, for example, bulkhead plates and stop log systems that are attached to building openings.
Any retrofit elements can of course be considered and installed when the house is being built. Also consider: Just because you have taken numerous protective measures, there is no guarantee that the basement will not be flooded one day. You should be aware of this.
Basement under water – what to do?
So it is important not to rush anything when the basement is under water. As frightening as a basement full of water looks at first glance – keep calm. If you do wrong, you could even endanger your life or worsen the damage. So, you have water in the basement – what do you do now, step by step?
1. Cellar full – what to do? Don’t go into the water!
Cellars also have a power supply. Therefore it would be life-threatening to step into the water. Instead, make your way to the fuse box and operate the main fuse to prevent short circuits. But now it is the case that the fuse box is often in the basement. So what do you do in the case of a flood in the basement, if you cannot access the fuse without stepping on the water? Then definitely call the fire brigade!
It is not just electricity that poses a risk. Hazardous substances that are stored in the basement could also have mixed with the water (e.g. heating oil). This is another reason why the fire brigade should be involved, as the Federal Office for Civil Protection and Disaster Aid (BBK) recommends. As a precaution, you can also turn off the water using the main tap until the fire brigade arrives.
2. Basement under water – let the water sink by itself
If the cellar is under water, it would be best to start pumping right away. But that can turn out to be fatal if you are in too much of a hurry. As difficult as it may be, in some situations you have to wait until the water level has dropped by itself. This is necessary when the water level is particularly high. By and large, the outside water level is lower than the water level inside the house should be. Only then should water be pumped from the cellar.
3. Notify the insurance company, document the situation and call in experts
It is clear that you have to get rid of the water as quickly as possible so that the drywall, wooden elements in the construction and insulation do not soak up. But you should discuss this step with experts. In some situations, pumping out is not recommended if the basement is under water – for example, if mud and water have even penetrated through the floor slab. Sometimes you even have to flood the cellar.
Therefore: Contact the insurance company to act correctly and not to lose your insurance claims. There you will be told whether you should get in touch with structural engineers and building experts. Then you can document everything. Take pictures of the situation. These things are documented later by the dedicated experts as well as after the water is gone, which you can also take over. Inquire with the insurance company to what extent an appraiser is necessary. Until then, leave everything as it is and don’t throw anything away!
4. Pump down
Before you start pumping, you should not only be sure that no more water is entering. The water table should also have returned to its normal level. An expert can best assess all of this. Under no circumstances should you decide for yourself, because mistakes can have bad consequences: from flooding to flooding to cracks in the masonry and problems in the statics of the house.
5. Start cleaning
You are finally rid of the water, regardless of the route. But the matter is far from over. Because now the cleaning takes place and it is more important than you might think. Any mud should be removed while it is still wet, because once it dries it can sometimes become as hard as concrete. Mud dirt on the walls can be rinsed off immediately. Don’t wait until it dries up. It is also important that mud and water do not come into contact with the skin, as these can contain dangerous substances. Wear waterproof protective clothing as well as gloves and rubber boots!
Mud that hasn’t gotten in through the windows or doors could be a warning sign. If this has penetrated through the sewer system, i.e. drains, or even through the floor slab, it probably means that the statics of the house are damaged. This is checked by experts.
Remove carpet and / or furniture. It is best to put them outside to dry. If this is not possible, at least lift the furniture by placing it on blocks or stones. This will allow the air to better circulate underneath them and dry the area. Also ventilate the basement rooms. As long as it doesn’t rain, the windows and doors can remain open without interruption.
6. Dry the basement rooms
Since the cellar was under water, of course, despite the pumping out, there is still plenty of moisture in the premises. To avoid mold, odors and other problems, the basement room should of course be dried. Simple ventilation is not sufficient here. Instead, get special dryers. You can both borrow them and buy them for prices between 100 and 150 euros.
However, construction experts point out that a dryer alone is not always enough. Screed, drywall, and hidden building materials could prove to be more of a challenge. For this reason, you should also hire an expert here. In addition to any impact sound insulation, this will also take a drill core in order to better assess the condition.
Tips to reduce potential damage from an underwater basement
- Educate everyone in the household about the importance and operation of the main fuse. Children in particular should know that they are in the event of a flood never enter the water should!
- Keep all items in the basement on shelves. These are preferably made of metal.
- All electrical devices are not placed directly on the floor, but at least 15 cm higher (e.g. on a pedestal).
- In high-risk regions, where flooding can occur more often, the electrical and heating systems could be relocated to the upper floors.
- Be careful what you store in the basement: avoid dangerous substances and valuables.
- You should secure heating oil tanks by anchoring them. If the cellar is under water, they could float up.
- Wallpaper and carpets are less suitable for basement rooms. Opt against standard screed and also use tiles.
- Sockets should be higher up in the basement.
What to watch out for after the disaster?
- For the time being, do not drink tap water. Instead, use mineral water, even for cooking!
- Before using the drinking water pipes again, rinse them thoroughly.
- Do not eat or smoke while cleaning up! Fire (e.g. from matches or lighters) must also not be used.
- The electricity and gas lines as well as electrical devices are only switched on again as soon as everything is dry. This decision should be made by a professional.