Welcome to our latest Pro-Follow update as contractor Steve Wartman and his crew remodel an unfinished basement. If you’re just joining us, the guys have framed the walls, run duct work, and had the electric rough-in completed. You can read all about the progress so far at these links:
Today’s article will focus on insulating the walls, band-boards and ceiling.
Quick Note on Plumbing
I didn’t spend time with the plumber as he was only re-routing a few supply lines to keep them out of the way and ensure shut-off valves remained accessible. Since the homeowners aren’t adding a bathroom or wet-bar, the work was quickly done. Check out the plumbing rough-in for the other Pro-Follow basement remodel if you’d like to learn more about this step of the remodel.
When you finish your basement, adding insulation is an important step as an estimated 1/3 of heating costs can result from an uninsulated basement (Timusk, 1981). In addition to many building codes now requiring basement insulation, it’s a must-have for homeowners striving for improved energy efficiency. The difficulty is insulating a basement without ignoring moisture concerns, and the confusion about vapor barriers (which I address in Day 2) only compounds the problem.
Steve’s approach to insulating a basement here in Maryland starts with water infiltration. This is an older house, and it’s reasonable to expect 15+ year old construction to have completely settled. That’s important because otherwise new cracks and weep-holes may yet appear in the foundation providing an entrance for water. As it is, Steve and his crew can inspect the walls and use a waterproof sealer to fill existing gaps (before framing the walls).
While the homeowners already condition the air in the basement and have indicated no problems, concrete block walls are never completely moisture-free. The goal becomes ensuring the wall assembly can dry to the interior since walls below grade can’t effectively dry to the outside, and that’s the reason Steve opted not to install a vapor barrier. Then moisture can be removed by ventilation or dehumidification.
Step 10a: Insulate Walls
Steve and his crew insulated the walls with R-13 fiberglass batts installed in the stud cavities and secured with staples.
Pro-Tip: Most of Maryland is required to have at least R-38 ceilings, U-0.35 doors and windows, R-13 walls, R-19 floors and R-10 foundations. Find out the requirements for your state by viewing the state specific research PDF.
The guys wore protective masks to prevent breathing in the fibers while they worked.
When necessary, they’d cut the insulation with a utility knife.
Steve’s crew cut around outlets, pushing the insulation behind the box.
The area around the clothes washer and dryer will not be completely covered with drywall to provide easy access to the appliance hookups. For this area, they used an encapsulated insulation to avoid that “insulation smell” from off-gasing formaldehyde used to bind the glass fibers together.
Step 10b: Insulate Band-Boards
To insulate the band-boards, Steve’s crew used R-38 fiberglass batts. Band-boards need a higher R-value insulation because that is where several framing components (top plate, rim joist, subfloor) meet providing more opportunity for air infiltration. Band-boards also lose a lot of heat due to convection (heat transfer via air movement). Finally, unlike most of the walls, the band-boards do not benefit from the insulating effects of being below grade.
Step 10c: Insulate Ceiling
Lastly, the guys installed unfaced, R-19 insulation between all the floor joists for sound control.
The insulation was held in place with these insulation supports that bend in between the joists.
Since the electrician installed IC (insulation contact) rated recessed lights, Steve’s crew could run insulation right up against the outer shell.
Our next Pro-Follow update will focus on hanging and finishing drywall. Stay tuned!