quick 'superdoor' question

I'm building two doors based on Rod's 'super-door' design.. solid core door->sheet lead->mdf Here's the question. The 'top' layer, the MDF, is set back from the edge by 1" to create the 'stepped' door seal.. do I run the sheet lead out to the full edge of the door, or trim it to the size of the MDF? I was going to run it full width, but was a little concerned about having exposed lead around the edge of the door (with nothing but primer/paint covering it). thanks!

In order to have "full" isolation, I'd extend the sheet to the edges of the door. You can add another, thin, piece of wood sandwiched between the lead and MDF to cover the whole lead sheet. (hell, you can even make that sandwiched piece a thick piece of MDF, more mass, more isolation!)

That's actually a good thought, Ro.. maybe a thin piece of 1/8" masonite or something? Just enough to cover the lead.

FWIW - in my design the lead stops at the edge of the plywood sheet. I do not know how much luck you will have trying to install a piece of laminate on the face of sheet lead. Rod

Thanks Rod... so no real benefit to going out the full width? Any issue using 3/4 MDF instead of ply (other than aesthetics?)

biggator wrote:

Thanks Rod... so no real benefit to going out the full width? Any issue using 3/4 MDF instead of ply (other than aesthetics?)

Not Really & No issue Rod

Thanks, Rod! My rooms are almost done.. and I think we have a winner. We (my contractor and I) followed your book pretty closely, and were pretty careful and the results look very promising. The first test we did was with only ONE layer of sheetrock up in the drum room (there is now two plus greenglue) and we just stuck some sheetrock over the door and ran a compressor in there. At 1m, it was measuring just over 100db... and directly above the room upstairs it was virtually inaudible... will be doing full tests soon - but I think I owe you a big 'thanks!' "-)