This is about the gap between the top of the cabinet door (or drawer front) and the top of the frameless base cabinet.
After the countertops are installed that is also the gap between the door (or drawer front) and the bottom surface of the countertops.

Till now, I have been doing it with 1/4" gap, but I haven't been using any particular industry recognized systematic approach (if such thing even exists) in cabinet building, apart from my own, and could make it however big I want it.

But I'm switching to 32 mm and one of the systems uses zero reveal at the bottom and 3 mm reveal at the top, with cabinets height being multiples of 32 mm. This makes it possible to stack cabinets while obtaining same reveal (3 mm) between doors on stacked cabinets.

I am worried if 3 mm gap between drawer fronts (or doors) and countertops is big enough for whatever problems may later occur, like swelling of the bottom side of laminated countertops with particleboard substrate due to moisture or slight misalignments of hinges and such...

Of course, I can cut sides of just those cabinets that have countertops on them a little bit higher, i.e. 772 mm instead of recommended 768 mm (= 32 mm x 19), thus increasing that gap to 6 mm, but would rather not if it's not necessary, because those would require additional settings (or jigs) on the construction boring machine.

Thank you for your opinions,
O.

Id imagine only you can answer that based on your jobs/contractors/etc.. Whether or not you need more fudge is simply a factor of manufacturing and jobsite tolerances no?

I myself, regarding the tolerances of my fabrication and installation processes, do not need it.

But I'm curious if the customers (but not my current ones), or countertop people, or the nature of wear & tear do.

From the first book I read on cabinetry few years ago, and than browsing around, I got an impression that 1/4" is something like a standard, but than again I've seen all kind of things in the field, but mostly within a certain narrow type of customers, all very alike, that do not care much about such details, so my real word experience is accordingly limited.

My current customers barely have a cue what a cabinet is, so not much help from that side.

What are the rest of you doing and is it ever an issue with people from construction industry, like architects, designers, GCs... who know a thing or two about cabinetry?

Make it 6mm, that's close to 1/4".

I use a 1/4" when I do Euro cabinets.

I've been allowing a 1/8" reveal at the top of my cabinets for 30 years. 20 and 30 years ago before 3cm countertops became the norm and subtops were required this could be a problem. Back then virtually every countertop fabricator needed major hand holding during the templating process. Over time things have gotten better, mainly because of the prominence of 3cm tops (which don't require subtops) and more familiarity throughout the countertop industry with frameless cabinets.

3mm works quite well. Every front is 3mm short in height, 1 1/2mm top and bottom. I slide my pattern down so the door is flush at the bottom leaving 3mm at the top under the counter top. Layout would be 768mm with a 108mm toe kick. 876mm or 34 1/2". (normal kitchen) Hinges are 94 1/2mm from each end on all doors except the sink (158 1/2mm) because I don't use a false front but run the doors to the top of the cabinet. this leaves room for a 124mm face behind the door and in front of the sink.

Thank you all for your valuable inputs.

I think I'll try 3mm reveal at the top, flush at the bottom and stackable boxes.
In the meantime I think I red every thread on this forum regarding this question for the last twenty years and it seems 3mm is generally considered ok.

Bruce,
your setup is what my current working theory looks like. I'm just waiting to see what kind of metal drawer boxes I will be able to reliably source in my area and to check if those play well with that hole pattern, before I make it official.

All the best,
O.

I use Blum Meta Box, works well with this layout.

That's what I wanted to use in the first place, but I'm still trying to find reliable seller.

Yes. It's enough.all of our cabs are made like this