The outside of my windows are getting so grimy it makes my whole apartment look worse. Is my landlord obligated to wash the building's windows, and how can I get him to do it?

Unless the situation is particularly extreme, you're not likely to have much luck forcing your landlord to get the building's exterior windows cleaned, say our experts.

"You first have to look at the lease and see if it addresses window washing at all," says Sam Himmelstein, a lawyer who represents residential and commercial tenants and tenant associations. While landlords are obligated to perform certain upgrades, like painting, every so often, there's no clear rule in place when it comes to washing the windows.

Moreover, unless your windows are the tilt-in variety that are easy to clean from within the apartment, your landlord isn't likely to want you taking matters into your own hands.

"Landlords don't want tenants climbing out windows, for obvious reasons, and because of insurance concerns, they also don't want you hiring your own service," says Himmelstein. (If your window washer of choice doesn't have appropriate liability insurance and is injured on the job, the landlord could wind up with a costly lawsuit on their hands.)

If you're a market-rate tenant, there's not much you can do beyond writing your landlord a letter requesting the cleaning, and if they don't, taking your hard-earned rent money elsewhere the next time a lease renewal rolls around.

If you're rent-stabilized and the landlord used to maintain the windows with some regularity and has ignored your written requests, you could apply for a reduction of services rent abatement with the DHCR, though Himmelstein says that any abatement you might be granted -- and that's far from guaranteed -- isn't likely to be too substantial.

If the windows are so filth-encrusted that light can no longer get through, you could file for an HP action -- Housing Maintenance code requires that every bedroom have a window that provides a certain amount of adequate lighting -- but this is an extreme and unlikely case. "Write a letter and complain, but in terms of enforcing anything, the options seem pretty limited," Himmelstein says.

Virginia K. Smith is the senior editor at BrickUnderground.com, the online survival guide to finding a NYC apartment and living happily ever after. To see more expert answers or to ask a real estate question, click here.