Need advice please. have island 10ft long island x 4ft 2" (50inches)wide. overhang will be 12 inches down the entire 10ft length. have 24"d base cabinets plus another 12"d set of base cabinets back to back. (36 inches of base cabinets that granite will sit on). question is how many support posts will be needed down the 10ft length of overhang ?(14inch overhang) Will one support post on each end be sufficient or do I need 3? can't add metal supports into top of cabinets, not enough space between the cabinet doors and top of cabinets. no room for corbels. support posts are the only option. would like one on each end vs adding one in middle. help!

Measure the depth of the washer and dryer to determine the depth of the countertop. Leave about 6 inches for the water-hose connections and the dryer vent. Measure for the height of the counter, leaving about an inch between the counter and the appliances.

You need to decide on the exact model and check the user manual or installation instructions for that model as it will tell you how deep the machine is and how much space has to be left behind it for the hoses and plugs and how far forward the countertop can come over the top of the machine without interfering with your ability to use the machine. Most of the newer washing machines are much taller than the normal counter height. I think that all of the duets exceed standard kitchen countertop height and depth.

If that is all you are talking about, then the real question is what kind of countertops are you thinking of putting on? Is your space similarly enclosed on three sides? If so, The person installing the countertop will likely just to deal with this. For instance, the fabricator will likely just deal with this. If you are installing granite, the fabricator will want a full sheet of supported plywood but if you went with Corian, then under Corian the fabricator would want just some narrow strips around the edges to allow the material to expand and contract. I would look into the countertop before buying any type of cabinet, as there may be no reason to buy a cabinet.