A child is home sick.
An earthquake caused cellphone outage.
You need to stop and prep for an approaching hurricane.
(Yes, I'm talking to you east-coasters.)
Sometimes our workdays don't go as smoothly as we hope. When those days happen, use the freedom you enjoy working from home to make adjustments. We have the luxury of working whenever we choose. Take advantage of that luxury. When your Internet goes out, head for the local library or coffee shop. You won't be quite as efficient as in your home office, but you'll get some work done. Sick kids are trickier. Get up early and break your tasks into small bites that don't require hours of concentration. If your phone service is overloaded, use Twitter, Facebook and email to communicate. If you need to stop and prep for an approaching hurricane… well, it is best to stop and prepare.
Designate an "overflow" time in your workweek. When things go smoothly, you won't need it, but when they don't, you'll know it's there and relax a bit. I designate Saturday morning until noon as my work overflow timeslot. About once a month, I use it. I don't like giving up even that much weekend, but it keeps me clear headed when my workday falls to pieces. I know people who would rather catch up after dinner or get up a couple of hours earlier than usual the next day. Do whatever works for you.
We can't control all the deadlines in our work lives, but putting off tasks and projects until the last minute is asking for trouble, even in the conventional work world. Finish up a project a day early or submit your report or article before the deadline (gasp)! That way, when your workday falls apart -- and at times it will -- you have wiggle room.
