In places like North America where strict building codes are enforced, there are three important factors that should concern everyone who is thinking of not properly consulting and building to those specifications:
1. Inspectors and authorities will act against your non-codeworthy plans and builds; maybe today, maybe tomorrow, maybe after a few years. Perhaps they'll level a fine, perhaps they'll order the complete demolition of it by their own appointed workers or contractors, at your own expense.
2. Insurers will never pay out for damages caused to or by your non-codeworthy builds. It is the perfect excuse for them to not pay out. It doesn't matter whether your design has qualities that you can demonstrate are equal or superior to officially recognized standards, you lose.
3. If someone is injured or dies on your non-codeworthy project, you'll fail a ton of personal injury and other legal challenges at your own expense.
Our village (here in the USA) is pretty strict about the inspections. Each deck has to have 3 inspections (holes, framing, final).
If you build without a permit, the village will not allow you to sell the house (each sale has to have a village inspection) until you _tear down_ and redo the work with a permit.
So it's a lot more controlled than other places and they can enforce it by tying up the sale.
Similarly, I've lived in low-lying, high moisture land areas where local authorities were extremely strict about people needing to use only approved footing plans. I've also lived in forested areas with strict codes and rules on fire mitigation and prevention, so tree and scrub proximity was a very serious concern.
1. Inspectors and authorities will act against your non-codeworthy plans and builds; maybe today, maybe tomorrow, maybe after a few years. Perhaps they'll level a fine, perhaps they'll order the complete demolition of it by their own appointed workers or contractors, at your own expense.
2. Insurers will never pay out for damages caused to or by your non-codeworthy builds. It is the perfect excuse for them to not pay out. It doesn't matter whether your design has qualities that you can demonstrate are equal or superior to officially recognized standards, you lose.
3. If someone is injured or dies on your non-codeworthy project, you'll fail a ton of personal injury and other legal challenges at your own expense.