Floor Under Bath Tub

All in floor bathtubs feature overflow systems that also can be integrated into the bathroom design very well.
Floor under bath tub. A standard bathtub can hold between 40 and 60 gallons of water. The most common reasons to replace this floor are that it can no longer support your bathtub and the wood has become rotten. A rotten floor a leak or even termite damage are some of the explanations why the. Excess moisture in the subfloor is a common reason for early replacement of bathroom flooring but it can be prevented by choosing the right material from the beginning.
The floor framing for bathtubs requires special attention. Bathroom floors are notorious for suffering water damage and the area under the bathtub is no exception. By choosing the right material from the start your bathroom will stand a better chance of withstanding long term damage. You must consider all of the weight the floor joists must be able to support.
All the plumbing is done under the concrete and in tub areas they keep a area to allow for the p trap. Flooring repairs can be intimidating but the subfloor under the tub generally consists of. So yes this is normal. Keep in mind this is all done before the walls roof are done so the hole also allows for some changes to the where the tub sits.
If your house floor is concrete then yes this is normal. Such design makes tubes easy to get in and out because there is no need to climb over and out of the standard tub.