The sun emits both ultraviolet A and B rays. Typical home windows block most ultraviolet B (UVB) rays, however some UVA rays can still penetrate. Since both UV types have the capacity to damage skin and cause skin cancers, you need to protect your indoor environment from both. Fortunately, there is a solution: installing protective residential window tinting can help prevent harmful UVA rays from getting into your house and in your skin.
To understand the amount of sun damage an un-tinted glass lets in, take a look at the items in your home hit directly by sunlight. Do they appear faded or brittle? If the sun can do that much damage to your home furnishings, it can just as easily inflict the same amount of damage on your skin.