As far as I know yes they can do it.

They do it here.  Every year they send out a list of the next years observed holidays in December.  

As some point between February and Summer they will decide that they want a shut down for the week of Thanksgiving.

The most flexible they'll officially be is to allow you to take unpaid leave to cover that week.

In practice my manager has made allowances if people have already made other plans, I'm not sure about other departments.

KENAT, probably the least qualified checker you'll ever meet...

Yes, often times, people vacation time gets "re-organised" for them.

I have been at some employers where they will reimburse you should you received approved vacation time. If it hasn't been approved, then you are on your own.

At others, you were out of luck.

It never hurts to talk to your manager though. Good luck with it.

"Do not worry about your problems with mathematics, I assure you mine are far greater."   
Albert Einstein
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Yes - they can do it.
No - you don't have to put up with it.

You need to decide whether you job is worth this nonsense (very few are).  Tell your manager that you have already scheduled your vacation, have non-refundable reservations, and you are going on the vacation. Period.  Tell them you will be happy to schedule additional paid vacation during the shutdown.  If they give you grief, start looking for a new job.  If they give you any indication that they may fire you over this issue, be sure to take home all personal items from your office before you go on vacation.  That way if they fire you while you are gone you won't have a hassle getting your things back.

Just to bring in the European (Scandinavian) view. Vacation is regulated by law in Scandinavia about the same way for each single country.

And - yes they can. A major part of your vacation may be required to be taken within a certain periode, for instance during summer shut-down.

In addition generally obligatory vacation if the company closes down for shorter periodes during Christmas, Easter etc.

If anything left of your vacation, or unpaid, or companies with geneeral 'no shut down periodes', you have a mutual commitment: you as an employee have to agree any vacation time with your employer,'if suitable for the company'.

The practice of the law is about how much the company are inclined to lean your way.

I did like the answer from SWComposites!

Some employers behave as if employing a person is doing the employee a favor (albeit true for some employees). On the other hand, some employees see it as if they come before the company.

And... to bring the American view:

We, as employees, need to look at this from an employer perspective sometimes, if the boss needs a  month shut-down for maintenance or whatever, he should be able to.

The boss is certainly entitled to close his place if he sees it as esential, managing a place comes before the workers' vacations.

The summerwide shutdown did not come out of the blue joe, I suppose this is known business by all, and even if unexpected, it may be better to do the shutdown than go belly up. And for employees, sometimes, it is better to take unplanned vacations than losing the job.

Assuming that the corporation is operating in good faith of course. There is often more to it than what appears on the surface.

apparently, you scheduled your vacation with your company and have made plans to do something with it.  it's common practice to force employees to use a percentage by a certain date or to allow vacation by a certain percentage of staff at any given time (first come first served).  

the way i see it, the company should permit you to take your vacation time as scheduled and allow you to go without pay for the time you haven't earned (or advance you time) to have the shutdown. Otherwise, scheduling loses its meaning altogether and you won't be able to plan any personal activities as long as you work there. I'm sure everybody has some anecdotal plans made but having paid anything. so offer your reservations and tickets to your boss when you bring it up will help differentiate you from the pack.

After the office politics cool down this fall, ask if there are any shutdowns to plan your vacation around in 2008.

If you work in an industry with scheduled shutdowns and a history of forced vacation dates then why did you plan a vacation outside of those dates in the first place?

Did you ask for the time or did you go ahead and make your vacation plans without any sort of approval of the time off from management?

Management has a right to expect you to work when you are scheduled to work. Until vacation is approved then they have the right to expect you to work every day until vacation arrangements are made. They also have the right to schedule vacation dates around shutdowns etc. This is common in manufacturing as everyone is needed when the plant is operating and no one is needed when the plant is shutdown.

 Shortly after graduation one of my wife’s (nursing) classmates was too junior to get the better vacation slots and her husband was in manufacturing and had scheduled shutdowns in July every year. It was about 10 years before she had sufficient seniority to get a vacation that coincided with her husband’s.

If management approved the time off then they share the responsibility, either allow you paid or unpaid vacation time for the period of the forced shutdown, reimbursement of the non reimbursable payments for the vacation dates or some other equitable arrangement.  If they had agreed to the dates and are now saying too bad so sad then I’d be taking a walk as this is not a good company to work for.

If they were not consulted or did not agree to your dates then you are on your own with three options.
1)    Quit over the issue.
2)    Take your time as you scheduled and risk getting fired. (big risk)
3)    Reschedule your vacation to match the company dates and pay the money for the deposits.

Personally depending on how much I wanted the job, ease of getting another job etc I’d go for option 1 or 3. Never option 2 as being fired makes the next job a lot harder to find.

Rick Kitson MBA P.Eng

Construction Project Management
From conception to completion
www.kitsonengineering.com