I'm a renter. My landlord doesn't fix things all the time. They have fixed things but this house is such a project that many things get ignored and some things don't get fixed at all or fixed right. I had rodents and had to repair several holes but one place that is eroding is under the claw foot tub around the pipes. The floor is a crumbling mess. It's no time at all until it is a hole to the outside. I can't hammer under it because the tub is too close. Also the floor is warped and uneven so laying a board on top leaves gaps all around it. I can't afford someone to repair it but I need it fixed. I can't move the tub or remove the pipes. I thought about filling it with spray foam but that seems flimsy and not really a solution. Could I use cement and if so, any tips? Any other suggestions would be so appreciated and helpful. I'm just a disabled woman so I need something easy please. Thank you.
If the issue is rodent access, steel wool is helpful because they don't really like to bite metal.
If you stuff the hole with lots of steel wool (coarse), then seal it in with spray foam, the rodents will probably be discouraged (we don't eliminate vermin, we manage them). And the foam is easily removed once the landlord gets a conscience.
First of all, I would find a new place to rent. Landlord's are obligated to address issues like this, and yours is no exception. This will not be a very easy fix. The only way to fix rot in your sub-floor, (which is what this looks like), is to take the flooring up, and remove all of the rotten sub floor and replace it. Anything short of that will be putting a band-aid on a gunshot wound. Also, it would be worth a google search of your landlord's legal obligations. Letting wood rot like this is an invitation for all kinds of mold, which can be a serious danger. I would consider very seriously getting legal advice from someone.