Building a shelf over the washer may be an ideal solution. It would allow any brand/model of dryer to go up there ... and (theoretically) eliminate the need to physically remove the dryer from atop the washer if the washer needs service.

Assuming the washer's plumbing connections will be behind it, you MUST make sure there's access to turn off the faucets, disconnect the power and so forth in case of a problem or flood situation.

thanks for your thoughts dadoes and the good points if we do go that route. We may well do that but I would like to know if I have any other options. The cost of building the shelf might outweigh the cost of buying a new washer along with the new dryer.

Just know that with out very good solid structure beneath the dryer you could have some serious vibration, might want to check out vibration mats or pads etc. The high velocity spin really benefits from a very solid structure under it.
Would hate to see it vibrate right off of the shelf, attaching it might be a good idea.

ravencajun - I am confused by your advice because it is the washer that is on the floor. The fl washer does have a high velocity spin and vibrates quite a bit. But would a fl dryer also have a high velocity spin and lots of vibration? I currently have a top loading dryer and it doesn't do that. It is the dryer that would be up on the shelf.

r