Can a woman file for maintenance while still living in the same house as her husband?

Yes, you don't need to be formally separated or living apart to claim maintenance — the right to maintenance arises from your husband's obligation to support you if he has sufficient means and is neglecting or refusing to do so, which can exist regardless of whether you're currently living together.

You can approach a magistrate seeking a maintenance order under the general maintenance provision, or pursue domestic violence law's monetary relief provisions if the refusal to provide for you also amounts to a form of economic abuse, which is specifically recognised as a form of domestic violence.

Courts do examine the specific circumstances closely in such cases, since continuing to live together can sometimes be looked at as a relevant factor, but it doesn't bar your claim outright. It would help to document specifically how your husband is failing to provide for your basic needs, and to consult a family lawyer about the most appropriate application to file given your specific circumstances.