A sliding door is just a big window, and if correctly built in (check if the glass is the correct sized for the door if a bit old) with the correct sized lintels this should not be a big problem as the loads would be transferred to the sides, allowing the door to slide easily. Silicon spray (being a Yachtie were we use this stuff everywhere), we now use silicone spray on all our windows in our 1930 home and the windows glide across with one finger before they used to tilt when trying to open them. I would place the door head up to line up with the others and one thing you might consider is placing a window seat, (rebate the bottom channels into the window seat) and have the window seat in and out, place a cushion over the entire seat, should be fantastic and if the deck is built, than no balustrade is required. If it is a stacker slider, i would do the seat for the entire length. So instead of looking a bit funny they will think it was supposed to be like that. We should all think outside the square more often. RAM

Oklouise and Sirius, thanks for the ideas. Actually the first one could work us very well, removing part of the wall and having a partition instead of a door. A lot more work but we are pretty handy. Regarding the barn door, most of the people I talked to agreed it might date quickly, unless I use a different mechanism than the ubiquitous black one you see everywhere,maybe.

Dr Retro's analogy with a convertible are so true. We elected to wait 12months in our recent house purchase before embarking on major renovations. The magnificent view that we thought we needed to have stacker/bifold doors for turned out to be too breezy to have the doors open for more than a few days a year. So the extra wide mullions associated with this kind of door would be impacting the view for 99% of the time. In the end we went for extra wide sliding doors (3 for a 4.6m width) with the narrowest mullions we could find. As for your quandary re the corner post, how about a very small section solid stainless steel post? Along the lines of Miles van der Roh's Barcelona Pavilion?

If it is bare particleboard then my short answer is probably no, it is not worth paying double for better quality doors. Like I said, I haven't seen unfinished particle board inside cupboards in a long time. If it is laminated particleboard then it might be worth it. Like The Joinery Store said, laminated interiors are typical. Plywood is not unheard of (and I think it is more common in some other countries) but it would be unusual if you did not specifically request it. Just to be clear, the cupboard has been built and has laminate doors, and you are getting quotes to change the doors? For what reason are you thinking of changing them? What do you want the doors to look like from the outside? Do you want them to match any other doors or features in the room which are timber or poly?