1. Removed the first layer of drywall from the wall to expose the stud framing. Set up a table saw to rip the 2×4 stud material down.
2. The red boards are 2×1 furring strips we cut down to run around the perimeter of the wall.
3. Cut 2×4 into 2×1 furring strips.
4. Apply Acoustical Sealant to the 2×1 furring strips. You want to make a good seal between the original wall and the newly added 2×1.
5. Position the furring strip into place.
6. Firmly press the furring strip against the bottom plate.You will continue these steps around the perimeter of the wall.
7. Closeup of the the newly added 2×1 furring strip.
8. Secure the furring strip with nails every 8-16 inches. Always follow local building codes.
9. Remove the existing wall insulation. If you are lucky you can keep this and reinstall it after the new set of studs are installed.
10. Install the new wall studs 16″ o.c. The new studs will fall in between the current wall studs (so the completed assembly will be 8″ o.c.).
11. Continue installing studs. Since this is a rebuild we are toe-nailing them in place. A nailing gun is always helpful if you have one available.
12. Cut insulation down to fit in between the studs. You want to make sure it fits into place. In this case, I cut the insulation into 6.5″ strips.
13. Gently place insulation into the wall cavity. You may wish to use paper faced insulation so you can staple into place.
14. Continue installing the insulation.
15. Top view of the wall framing. The top plate has been removed to show the staggered studs.
16. A diagram illustrates the staggered stud effect.