I have this same question but am relocating my washer/dryer in our converted garage along with a game room. We have completed the demo of the 500 sq ft room and are ready to start putting stuff back in so we went to Home Depot today to just ask some questions. The assistant at the cabinet and countertop station told me I needed an 18 inch clearance above my dryer to allow for ventilation. He advised me to look in my owner's manual so I did that tonight and it said NOTHING about clearance needed above an electrolux dryer (which stands 36 inches tall). I have seen pictures of other washers/dryers (even stacked) and in enclosed spaces so I'm confused! I definitely want to hide my units along with gaining a better space to do the laundry but don't want to screw up my 9 month old machines.

MIele, Asko and Bosch all have machines that will fit under counter. They need to be shorter than 36" if you are going to put a counter on top of it. Asko still sells an integrated Washer and Dryer that you can cover with your cabinet panels, just like a Dishwasher. I think the Frigidaire front loader may also be able to fit under counter. I am only referencing the front load washers.
Good luck!

While I love how the ventless WD cleans the laundry, drying time is really long and b/c you can only dry half of the load you wash-otherwise it will be very wrinkly-you double the drying. Average drying time easy up to 2 hours.
I still have my Supra but it is only used for washing now. Also the heating element didn't last only a year and the condenser need to be cleaned often.
Unless you have no venting option,don't get ventless dryer.

Thank you! Hmmm...I wrote a response yesterday but it never appeared. It looks like it's the expensive brands that have the under the counter option! :)

Since you said it's little, wouldn't a stackable set be a better alternative? The under counter may look nice but you also lose that floor space. Might be an impact or might not. Just a thought.

go to compact appliances.com and check their products.They have all measurements listed. Maybe it will help. They have lot of stuff there.

Gideonsmom,

I have the 36 in Whirlpool Duet Sports. They are smaller than a full size duet so they would make under the counter installation easier. I've had mine for 2 years and not had a single problem out of them. I leave the door open slightly and wipe down the gasket when I am not using them. I am washing for a family of 8 so they get a lot of use. Even for the smaller size, they keep up with all our laundry so much better than my TL ever did. I love them!!!

compact appliances.com has several choices. Depth starting just litte bit over 25".
I bought from them before, they are very nice, quick shipping, cheap extended warranty and they run specials.

Any issues with heat or moisture venting beyond what one would need to deal with for a dishwasher?

I don't think so. DW uses much hotter water than washer. Even when I used my WD combo( the ventless one), there was no moisture to be felt around. The unit felt warm (enough to dry towel over it) on drying cycle but my dishwasher puts out more heat- it is old piece of wonder, fixed manytimes.
Besides look at the build in ovens, even thou they vent up front, I'm sure there must be some heat in between cabinets. I wouldn't worry as long there is no water drip when draining. In europe we use appliances build in the kitchen for years.