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Measure your sofa length. A good width for artwork over a sofa is two/thirds the length of the sofa. Round up or down to the nearest standard size. Frame style is a personal preference. As for color, if you like coordinated things, pick art with some blue in it, like the sofa.

We built deck all around our above ground pool our pool has a 25 yr warranty so that was not an issue. All I see right now is a big mess and you need to think about the use of the pool and the deck Maybe a to scale plan of that whole yard and exsiting deck would be helpful. We have railing and a lock on our pool area which is code where we live. We have deck all around our house so about 2200 sq ft. I hate grass so no grass at all but we do have some nice landscping in the area without the deck.BTW we heat our pool with solar so the whole layout of the pump etc had to be well planned .

I think it’s fine with nothing. I have more space than that above mine, once I got the rest of the room decorated, it didn’t feel so bare. Love your light fixture!