I thought I should give a little run down in one place as to how I completed my coffered ceiling project just in case you want to try this project.
We then decided on our placement and found the ceiling joists and screwed the 2x4's to the studs, then added blocking to the studs , 2 blocks 5 at each connection and randomly along the lengths to attach the MDF boards. I had Home Depot rip down 3 sheets of 5/8" MDF into 5.5" strips.
I then used a 2x4 to set my table saw to cut the strips of MDF for the bottom pieces approx 3.5" wide.
You can see how I attached the MDF to the studs, I used my nail gun for this part.
We installed a plastic zippered door to keep the mess better contained.
There was such a mess caused by all the priming and sanding and priming and more sanding.
Then I added crown moulding and caulked all the seams and filled all the nail holes and then did between 2-3 coats of satin latex paint in Behr's Vermont Cream.
I used this new gadget from Lowe's to help me with the crown moulding, it just keep the crown moulding at the proper angle when you cut it upside down.
http://www.homedepot.ca/product/metaltech-steel-folding-scaffold-work-platform-500-lbs/938855
So if you have ever longed for a coffered ceiling like I have for years then maybe it is something you can do also. It is not a difficult project but it does take time and patience and have a helper for the initial stud placement is necessary but the rest I was able to manage on my own, I may have had to hold my nail gun in between my knees while I positioned the 8ft pieces of MDF but a girl's gotta do what a girls gotta do.
If you try this project please let me know I would love to see.