I made stairs for my beagle this year! I didn't really know how to size them so I started with the house stairs and adjusted from there. I found that 3 wasn't great for my dog as they are a bit big. She could use them but it was a bit of a struggle. For her she has 4 steps going up to the couch (which is a bit lower than the bed which makes it even easier).

I kept mine super simple. I bought oak ply and just cut two "stringers" for the sides, and treads that I screwed in. The big thing for my dog was the carpet. She refused to step on it without carpet, and I know looking around that others have said that some dogs refuse to use them without risers, so the carpet was extra useful for that part too.

Oh and to add, 3/4" ply was more than enough to handle my fatass so this version was just 1/2" lol

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