Across openings such as sink some manufacturers insert stainless steel
reinforcement underneath. Another idea is to double up the granite at the
front edges. Looks good and becomes very strong.

I'm not worried about the Belfast sink cutout. Apparently, the total length
of the worktop is way too large for one piece anyway, so there will be joins
at the Belfast sink. It is just the 1.8m section that will only be supported
on 3 sides that I'm worried about.

I have:

+----+----+----+---+----+---+---+
| WM | TD | DW | +----+ | |
| | | | 1 |SINK| 2 | 3 |
+----+----+----+---+ +---+---+

Support profile:
^ 1.8m ^ ^ ^ ^ ^

WM = washing machine (600mm)
TD = tumble dryer (600mm)
DW = dishwasher (600mm)
1,2,3 = units (500mm)

I could swap 1 and DW without too many plumbing issues. This would leave
another 1.2m gap, as the dishwasher and sink unit wouldn't be load bearing,
as far as the granite is concerned.

+----+----+---+----+----+---+---+
| WM | TD | | DW +----+ | |
| | | 1 | |SINK| 2 | 3 |
+----+----+---+----+ +---+---+

Support profile:
^ 1.2m ^ ^ 1.2m ^ ^ ^

The only other alternative is to move the sink over a unit as well, giving

+----+----+---+----+---+----+---+
| WM | TD | | DW | +----+ |
| | | 1 | | 2 |SINK| 3 |
+----+----+---+----+---+ +---+

Support profile:
^ 1.2m ^ ^ ^ ^ ^ ^

Although this gives the best support profile, this leaves an unbroken 2.8m
length of surface, with only a small 500mm on the end next to the sink, not
enough to put the microwave on. The sink can't move further right or left
and I strongly prefer the lefthand position.

Christian.