When I made my board larger with plywood, I was told by a quilt shop owner to drill some holes where the main ironing will be done. It seems they made some for the shop and wondered why their steam irons were always burning out. Said the steam had to get out or it does something to irons to burn them out. When I look most ironing boards do have holes in the top (before you put the padding on) Not sure if this is true, but mine works OK with the holes drilled. I put layer of insulbrite then layer of cotton batting then top fabric. Has anyone had the problem of burned out irons?