Which building regulations make new constructions so expensive?

Parking regulations also occur with single-family houses, I just remembered.

But I think it primarily concerns multi-family houses:

Accessibility: In all buildings with more than two apartments, according to MBO, the apartments on one floor must be accessible barrier-free. They must be located on the ground floor if no elevator is available. The rooms of these apartments must also be barrier-free, except for guest toilets or a second bathroom. An elevator is mandatory in most federal states from 3 residential units upwards.

Fire protection: The higher the building class, the more comprehensive the measures to protect residents in the event of a fire must be. From building class 4 onwards, the fire protection concept must come from a specially trained expert planner. The concept must cover the following aspects of preventive fire protection:

[*]Structural fire protection: This includes separate fire compartments or access for the fire department.
[*]Technical fire protection, such as fire extinguishing and smoke extraction systems.
[*]Organizational fire protection, such as the marking of escape and rescue routes.

Soundproofing

[B]Ancillary rooms [/B]Basements, bicycle parking spaces, playgrounds, minimum sizes for utility rooms, etc. are regulated in much more detail than in single-family houses.

And an architect will certainly be able to name many more for you.

Spontaneous list with us:
- With us, there is presumably geogenic arsenic in the soil. It must not be reused but needs to be deposited. This stuff is completely harmless in the noise protection wall, but would have made the basement many times more expensive. We are now leaving everything on the property, but of course, this only works with a slab foundation.
- Retention cistern: 4 cbm of air buried, I would much rather use the water in the garden or house than discharge it into the sewer.
- Permeable paving on hardly water-permeable soils. The problem here is less the paving than the very thick base layers.
- Outbuildings with garages must be roofed or greened like the residential building. Good luck finding a garden house that can carry a tiled roof or the even higher roof load for greening. Same game with the carport. And aside from the construction, the tiles alone for the garden house are more expensive than some people’s kits (many special tiles).
- Massive subcontracting with utility providers. It’s outrageous how many companies come here separately, e.g., one company lays a microduct for fiber optics, and another blows the fiber through it, and then at some point another company comes to connect the fiber. One company lays electricity through the multi-utility line into the technical room, another installs the meter.

In our former residential complex there are currently problems. The gas heating is acting up; now the administrator has trouble achieving the 15% renewable share with a new heating system. Exceptions apparently apply to systems under 50kW; with residential buildings from the early 80s and 63 units, you are above that. Basement ceiling insulation or roof insulation will presumably be credited, but in practice, they bring relatively little, as with 9 floors it only affects the top or bottom one each.

Just read an article this morning, the Ministry of Construction and the Ministry of Environment are teaming up and now want mandatory photovoltaics and greening of roofs and façades. Another cost factor. And in my opinion, greening done poorly (because it’s mandatory) is worse than no greening at all.

I doubt that the energy requirements in residential construction are decisive. Usually, concrete + ETICS (external thermal insulation composite system) is built, and whether you stick on 10 or 14 cm of Styrofoam is the same work. As a landlord, I would install forced ventilation anyway; it pays off after a few years with the saved mold remediation.

Sure... for the technically skilled layperson, it may sometimes be incomprehensible why they have to have this or that done by someone else. But where do you draw the line? I completed an apprenticeship and studied electrical engineering... but I haven't worked on house installations for 18 years, so should I therefore be allowed to do and approve that myself?

Now someone comes along who has an apprenticeship but maybe as a carpenter. Should they be allowed to work on the electrical installation? When I sometimes read in the electrical forum what some laypeople intend or the general questions... I'm surprised more houses don't catch fire or people don’t die from electric shock. Some of the ideas people have are downright absurd. Or should a physicist with a diploma be allowed to do it, but not a mathematician?

By the way, many subcontractors actually make it cheaper, not more expensive. Why should the civil engineer buy special equipment for the 25 times a year they install fiber optic cables? He leaves that to someone who does it every day. That person also has much more experience and therefore does a better job. Above all, responsibility for the activities is transferred to the subcontractor. They are responsible to the client in terms of warranty... and so on.

Do you think we work with subcontractors because it makes us more expensive to the customer or because we make less profit?

PS: And a lowered curb is part of the public traffic area. Let something happen there and it comes out that it was not executed and approved according to recognized rules of technology. Good luck with the public prosecutor.

- Retention cistern: 4cbm of air buried, I would much rather use the water in the garden or house than discharge it into the sewer

One does not exclude the other. Retention cistern only means that there is a controlled overflow in case of heavy rain. Most of the cistern can also be used for garden water with a pump. Or have I overlooked something? We have an old pit (25m³) on the property. About 3m from the future house. There, the rainwater is discharged and, via retention, into the rainwater sewer. Due to the design, I can store less water this way, but it is better than nothing (overflow must be located lower due to the retention area).

(...)
I doubt that the energy requirements in residential construction are decisive. Usually, concrete + EIFS are used, and whether you glue on 10 or 14 cm of Styrofoam is the same job. As a landlord, I would install forced ventilation anyway; after a few years, it pays off with the saved mold remediation costs.

Same job, yes and no. More material costs more money. More material may not fit on one truck, so two trucks might be needed. Unpacking 10 pallets takes less time than unpacking 14 pallets, etc.

One does not exclude the other. Retention cistern only means that there is a controlled overflow when it rains heavily. A large part of the cistern can also be used for garden water by means of a pump. Or am I missing something? We have an old pit (25m³) on the property. About 3m from the future house. Rainwater is introduced there and discharged into the rainwater drainage via retention. Because of the design, I can "store" less water but it's better than nothing (overflow must be lower due to the retention area).

A retention cistern means the cistern has an outlet hose that releases water slowly into the sewer system (in our case rainwater sewer). This happens until the retention volume is empty. The 4m³ are basically not usable, because right after heavy rain I don’t need to water the garden. Overflow is something completely different. When the cistern is filled to the brim, it runs directly and unrestricted into the sewer. Of course, we didn’t just bury empty space, but enlarged the cistern accordingly so that the other 4m³ are usable. Still, that is a lot of money and in my opinion the retention function is not necessary if you use a cistern otherwise. The retention function is primarily intended so that during heavy rain not all roofs also drain into the sewer system. Although compared to the street surfaces it should not be that much anyway.

Same work, yes and no. More material costs more money. More material may not fit on one truck, so then two are needed. Unloading 10 pallets takes less time than unloading 14 pallets, etc.

Of course it costs money. But double insulation is not double the cost and whether it is now EH70 or EH40 building envelope makes significantly less difference than it seems at first glance. Especially in residential construction with many interior and few exterior walls.