I have 8 ft ceilings with beams in my den. Here's a pic I just happen to have in photobucket. There are 2 beams in the room on either side of the fireplace. They are about 12 inches deep, so the clearance is 7 ft under those areas.

{{!gwi}}

It depends upon the scale of the overall house. There are a lot of very old houses (18th c.) in my nieghborhood that have exposed beam ceilings (They probably were not originally), that are 8 feet or a bit under. They seem natural enough, but they do seem to bring the ceiling down a bit.

She has a 1960s ranch. She'd like to use stained cypress beams. This is an example pic she shared. Do you think it might work better if the beams were cut in half ... say 6" deep instead of 12" ...or not?

{{!gwi}}

I don't have a photo by my Aunt and Uncle had beams in their eight foot ceiling height living room. My guess is they were six inch beams. We'll be putting six beams into our eight foot ceiling Gentleman's Parlor.
Ours will be like these....
{{!gwi}}

Mine aren't "beams", but it's the same idea. I think my logs hang down around 8 inches from my 8 foot ceiling. It does make the ceiling dark and heavy, but it also makes it feel really cozy. So, if she wants a warmer element, I think they can work. If she's going for light and breezy, not so much.

Her photo show 12" beams. The LR justgotabme posted looks like 6" to me.

My kitchen is linked below. They are 6x6 and 4x4. Against the wall, the trim piece is 2x8. The large beam you see in the 2nd picture dividing the kitchen from great room is structural and it's 6x12. Hope this helps:

Here is a link that might be useful: My kitchen - beams

Thanks to all for the visuals! The 6-inch looks good. I'll give her a link to this thread and see if it helps.

You can get some very small dimensions from the fauxwoodbeams.com website, they are not real but from the images they look awesome

Here is a link that might be useful: fauxwoodbeams website