1. Most of my house is Revere pewter and it's an open floor plan. Since it's a greige, do I stick to either grays or tans in all of the bedrooms to create flow?
Colors commonly called grays or tans all belong to hue families. They're simply toned down versions of their hue parents like you see in the graphic below. You can find a gray from every hue family in the spectrum. Each row of child colors is about the same in terms of lightness and grayness. (These are all Dunn-Edwards paint colors, I left off the hue parent paint color info.)
But that doesn't mean all of them go together. Color relationships matter and the way you understand color relationships, how you know what colors go together, is a color wheel. Color wheels illustrate how colors relate to each other and those color relationships have names like complementary, analogous, triadic, etc. Once you know what hue family a "gray" or "tan" belongs to, then it's easy to figure out what other colors go with it. For example, here's a tetrad of near neutrals. (I love a scheme of greens and purples)
2. Can I do a warm paint color in the living room but a cool color in the kitchen that is visible from the living room?
Sure! The juxtaposition of warm and cool colors is one of the seven different kinds of color contrasts. (Johannes Itten detailed all seven.)
If you are going to combine warm and cool colors, it's easier if they are about the same in terms of how gray they look. Like you see in the images above.
3. If I go more yellow beige in the kitchen do I have to stay with warm accents?
Not at all. If you want your accents to have the most punch or pop, then using a cooler color would be the way to go to achieve maximum contrast and visual impact. If that maximum punch/pop is too much, then you go with warmer accents to lower the tension between all the colors so the visual impact isn't so intense.
4. I want to stay neutral for my wall color but from room to room, do I stay all warm or all cool?
Same answer as #2. Keep all the colors within the same range of grayness and it will work. They can be lighter or darker, but it will be easier to pull off if you don't try to mix vivid, clear colors with your muted and chromatic gray colors like Revere Pewter. For example, I wouldn't put a vivid, clear color like Sugar Cookie 2160-60 with Revere Pewter.
5. I would love to paint my baby's room a light tan but my hallway is more of a cool gray.
I would focus on choosing a light tan that works, harmonizes with the contents of your baby's room first. Then, I'd (casually) consider how it looks with the hallway color second. The interruption of a doorway between two room colors means you don't always have to work so hard at crafting perfectly harmonious wall color relationships; the doorway gives you more wiggle room for it to work and look good.
Don't get too hung up on "warm" and "cool" color labels because color temperature is relative. In other words, a color isn't warm or cool on its own. We never see color in isolation and context is what determines an individual color's temperature which means all hue can be perceived as warm or cool - it depends.
Technically speaking, warm and cool is not a continuous spectrum that splits the color wheel in half. Warm and cool is actually a spectrum within each hue family. There are warm blues and cool blues. Warm reds and cool reds. Warm oranges and cool oranges, etc. Like you see in this color wheel. The context for warm and cool in this case comes from the hue families in the color system that goes with this color wheel.
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backsplash , counters
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