Inefficient windows are one of the biggest culprits when it comes to winter heating loss. If yours are old, chances are they're not up to the job of keeping necessary heat inside your home where it belongs. Replacing those outdated windows, however, is expensive. Luckily, there's a temporary solution to prevent cold air from leaking through your windows. Try covering them with bubble wrap. It may look odd, but the bubble wrap will trap cold air pockets, while still allowing light to shine through the glass.