Can You Install a Metal Roof Over Old Shingles?
Why going over the top even works Metal panels are light, and that's the whole trick. A metal roof weighs a fraction of what shingles do, so adding it over one existing layer usually doesn't strain the structure. Most building codes allow two total roof layers, meaning one shingle layer plus your new metal typically passes. Check your local rules, obviously, but the door is usually open. The savings come from what you skip: no tear-off labor, no dumpster, no day of debris raining into your flowerbeds. The old shingles even earn their keep as an extra layer of insulation and sound damping. Not bad for a roof you were about to throw away. The one thing you can't skip Now for the honest catch. Going over old shingles only works if what's underneath is sound, and that means the decking has to be dry and solid. Cover up rotten wood and you've sealed a problem inside your new roof. That's not a shortcut, that's a time capsule of regret. So walk the att...