I am currently in the building permit / planning permission process and just found out through a call to the building authority that my property is located in the HQ100 EXTREME risk zone, so I have to take flood protection measures. This requirement has apparently been in effect since 2018 in Baden-Württemberg.
To explain: HQ100 EXTREME means there is a levee protecting my site next to the Danube River, but this levee could break (which seems very unlikely...). Because of this, I need to implement additional flood protection, whatever that may specifically involve. The exact wording states:
“At locations in risk areas outside designated flood zones, where no local land-use plan exists, construction projects may only be built or significantly extended using building methods adapted to the specific flood risk, according to generally accepted technical standards, provided this type of construction is technically feasible given the nature and function of the structure.”
I am building a solid structure without a basement, and my finished floor level is 61cm (24 inches) below this theoretical extreme flood level. I do not want to raise the ground level further. Although this would be technically possible, it would be expensive and would not look good.
I spoke by phone with the responsible official about whether I could build a wall around my property as a possible solution. She said she wasn’t sure if walls that high would be permitted there and reminded me to consider the entrance driveway. She recommended building 81cm (32 inches) higher for safety, but 61cm (24 inches) might be acceptable. However, I got the impression she wasn’t very knowledgeable. Maybe installing barriers or flood gates on the doors could work – I have seen sliding flood barriers online. Overall, this is really frustrating as none of the more than 100 houses nearby (all built before 2018) have anything like this, there has never been an extreme flood, and I think potential damage would probably be less than the cost of these measures. I also have insurance that costs an additional 100€ per year for flood coverage. To be safe, I will probably install my heat pump about 0.5m (20 inches) higher.
Does anyone have experience with this or a good idea on how to solve this as cost-effectively as possible?
To explain: HQ100 EXTREME means there is a levee protecting my site next to the Danube River, but this levee could break (which seems very unlikely...). Because of this, I need to implement additional flood protection, whatever that may specifically involve. The exact wording states:
“At locations in risk areas outside designated flood zones, where no local land-use plan exists, construction projects may only be built or significantly extended using building methods adapted to the specific flood risk, according to generally accepted technical standards, provided this type of construction is technically feasible given the nature and function of the structure.”
I am building a solid structure without a basement, and my finished floor level is 61cm (24 inches) below this theoretical extreme flood level. I do not want to raise the ground level further. Although this would be technically possible, it would be expensive and would not look good.
I spoke by phone with the responsible official about whether I could build a wall around my property as a possible solution. She said she wasn’t sure if walls that high would be permitted there and reminded me to consider the entrance driveway. She recommended building 81cm (32 inches) higher for safety, but 61cm (24 inches) might be acceptable. However, I got the impression she wasn’t very knowledgeable. Maybe installing barriers or flood gates on the doors could work – I have seen sliding flood barriers online. Overall, this is really frustrating as none of the more than 100 houses nearby (all built before 2018) have anything like this, there has never been an extreme flood, and I think potential damage would probably be less than the cost of these measures. I also have insurance that costs an additional 100€ per year for flood coverage. To be safe, I will probably install my heat pump about 0.5m (20 inches) higher.
Does anyone have experience with this or a good idea on how to solve this as cost-effectively as possible?
The insurance is already arranged; in my area, coverage for natural hazard damages costs an additional €100 per year. Insurers use their own system for this, so the surcharge varies, and in many flood-prone areas, natural hazard coverage is not offered even for an extra charge.
As I said, this is not a floodplain; flooding would only occur in case of an extreme event like a dam breach, and then to a maximum depth of 60cm (24 inches). The other 100 houses nearby have not taken any special precautions, and most of them even have a basement, which increases the insurance cost. One neighbor does not have any insurance.
As I said, this is not a floodplain; flooding would only occur in case of an extreme event like a dam breach, and then to a maximum depth of 60cm (24 inches). The other 100 houses nearby have not taken any special precautions, and most of them even have a basement, which increases the insurance cost. One neighbor does not have any insurance.
Let’s be honest… why does it matter to you whether the neighbor has insurance or not? It doesn’t matter at all. Your bank will require insurance, so you will have it. There’s no need to think about it any further.
The same goes for flood protection. The regulations have currently changed in a way that you must take action. You can complain all you want about whether it makes sense or not, but find a solution, otherwise you won’t get a building permit / planning permission. It’s that simple.
Ask architects in your region.
It might be enough if you make everything watertight up to 61cm (24 inches). Flood protection doors, no floor-level tilt windows, no sliding doors in front of the terrace, maybe no garage either, and so on. A local or specialized architect will know this.
The same goes for flood protection. The regulations have currently changed in a way that you must take action. You can complain all you want about whether it makes sense or not, but find a solution, otherwise you won’t get a building permit / planning permission. It’s that simple.
Ask architects in your region.
It might be enough if you make everything watertight up to 61cm (24 inches). Flood protection doors, no floor-level tilt windows, no sliding doors in front of the terrace, maybe no garage either, and so on. A local or specialized architect will know this.
You seem to reject everything. So what do you actually want to do now? You must have some final answer. Whether it will prove effective remains to be seen.
Your comparison with others doesn’t help either. Weather extremes have increased in recent years, and most likely this clause was adjusted over time to prevent disasters.
If it’s always been included, then just ignore it and build however you like.
Your comparison with others doesn’t help either. Weather extremes have increased in recent years, and most likely this clause was adjusted over time to prevent disasters.
If it’s always been included, then just ignore it and build however you like.
danixf schrieb:
You seem to reject everything. So, what do you actually want to do now? Apparently, to oppose the municipality.