Son 1 built a riser for my dresser turned ironing board. I already had a big board and just needed the dresser taller. He used two pieces of MDF and a 4x4 fence post I had the lumber yard cut into 4 inch long pieces. He used 8 chunks of the fence post and put two screws in the top and bottom of each one . There aren't any hole for steam. The big board has a layer of batting and a cotton duck cover. The cover has a pull cord and to make it real tight I used regular old thumb tacks to tack it on. I have a piece of that rubbery grid no slip cupboard stuff under the riser and it never moves at all.
I put it on furniture sliders so if I need it shoved one way or another it's not a problem to move it.
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