How To Air Seal Ceiling To Wall Connections In Attics

Loose connections should be clamped taped and caulked.

How to air seal ceiling to wall connections in attics.

Occasionally they ll put adhesive on the walls but usually they ll glue only the studs not the plates. Ventilate the attic 1 sqft per 300 sqft of attic floor space balance at ridge and soffit areas. Long piece from a batt of fiberglass insulation and place it at the bottom of a 13 gallon plastic garbage bag. Consider swapping out or upgrading any duct work that is not insulated properly.

In this video series we re going to show you some simple techniques and off the shelf materials that you can use to air seal up most all of the air leaks that you ll find in an average attic. It s usually the hardest place to air seal because the cramped space underneath the eaves where the roof rafters rest on the outer wall makes it hard to move your hands and head. Any ceiling vents need to be foamed and sealed where they meet the ceiling. Air seal all penetrations and possible leakage paths.

Sealing the ceiling so the attic insulation can work. When the furnace or air conditioner is on check for air leaks around the duct connections with your hand a lit incense stick or a thing piece of toilet paper. Plug all open joist spaces under insulated side walls. Use mastic sealant or aluminum foil tape not duct tape to seal all of the duct connections.

If you have an attic ac unit you should take this opportunity to check the air seals on the duct work. If they d simply run a continuous bead of adhesive on the top plate too they d block the pathway for air to move between attic and walls. So we re not going to see the top plate of the framing. Then insulate to at least the current energy code not only to the proper r value but also to grade i quality.

The best way to shut these huge leaks off is to sheathe over them at the framing stage. Attics often have other huge openings that many builders don t see as air leaks. We re going to show you how to seal up light fixtures in the ceiling the junction box for ceiling mounted fixtures as well as recessed light cans. So simple a solution.

Air sealing the wall plate around the perimeter of your attic blocks air from escaping around the outer edges of your home. Fold the bag over and stuff it into the joist space under the wall. Heated rooms built into attics often have open cavities in the floor framing under the walls. Mastic sealant paste is a slightly more effective and durable than hvac foil tape.

After the drywall hangers get the ceiling done they come back and do the walls. What we ll do is we ll seal that block to the drywall and that ll get almost all of the air leakage that s going to occur.