Earlier quoted context omitted.
Which regulations would you relax? Surely there is some unnecessary red tape, but it's not as if building regulations have been developed for fun, it's largely in response to safety issues and so on.
Cosmetic stuff, square footage requirements, height requirements, parking requirements. Basic structural engineering, fire safety, etc. requirements of course would stay but if local code is more stringent than national you might take a look at it (e.g. things like a local code requiring copper pipes when PVC is acceptable and much cheaper).
Developers will always attempt to skimp on quality to save/make more money. Even people building their own home will sometimes try to avoid compliance. That's why the regulations are there.