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@aa I don't put boards around the side. The boards I use probably have about 6in to keep the puck in in some places and a foot in others. My backyard is pretty wide open but if you are worried about flying pucks another option is netting on the ends. As for temp depends on how flat is your yard is for how long it will take to freeze everything. After that as long as you can have more freezing temps that above it should be ok.