The easiest way is to purchase base cabinets that will give you storage and shelves and install the counter on the base cabinets. Leave a space for sitting, the counter can bridge the gap. You may want to consider bath cabinets which are generally lower and would be the right height for a desk. Alternatively, you can install a 2x4 ledger board on the wall and frame in support for the counter. Again, this can be as elaborate or simple as you want. The frame needs to suppot the counter. The counter is too heavy to simply support off the wall, so you will need some front support. Even less expensive is to use 5/8 or 3/4 inch melamine coated MDF or particleboard. This gives you square edges with no backsplash. It can be easily cut to shelves, desk top etc.

I did a similar project some years ago, and it was serviceable as an inexpensive computer center, printer support and general office duty, but eventually switched to a desk for better appearance. The problem with counters is once they are in, you have a fixed arrangement which is not as versitile.

I'm doing something similar and can't take the easy way out of using cabinets as a base.

I'm installing a countertop without cabinets underneath. The countertop will go above a frontloading washer & dryer. I want to install the countertop between two walls 7.5' apart. The countertop is laminated particle board - not marble or other heavy material.

Will anchoring the countertop to 1x2s anchored to the studs (45 degree downward angle) be enough support? If not what would you suggest? I do not want the counter to be supported by the appliances.

Install a laminated partition between the appliances to support the countertop.......

Use ledgers on the walls to support the sides and back edges.......and to fasten the partition in place.....

Or you could build a "table top frame" with 2x4"s, supported with stock turned posts to the floor (and from the top's frame in the center as well if needed) on the "room side" and a ledger board installed into the wall framing then mount the "stock" laminated top to the "table frame" from below with screws. Cabinet manufacturers tend to have matching posts at "counter top" height AND at "bar" height as well as the availability of "lumber stock" turned posts unfinished. There is no requirement to frame in the sides of your countertop. You can also cantiliever it from the sides if your span isn't too wide.

Also to the OP: I did a similar project using "stock" 2-drawer file cabinets as my supporting method in certain areas, and turned posts in other areas, with a ledger board (mounted to wall studs)on the walls and fashioned a cantiliever support on my "open end".

I used 2x4"s on the skinny side to build my countertop frame and 2 each 2x6"s. picture a six-pocket door without the "pocket pannels" that's essentially how I built the countertop frame. I hung the "frame" then installed the stock countertop. I also installed "cord access" for appliances by ordering moulding kits from a partition office supplier, to make a nice finished look in my converted "office" space.

Good luck both of you in your projects.

I love using 2 x 4's to construct a whole lot of projects. You could build a base from 2x4's and cover with pine boards and then attach to counter top with L brackets underneath.