Batts Which Direction Attic Knee Wall

The bottom plate of the knee wall rests on the open floor joists and the top plate is secured against the roof deck rafters.

Batts which direction attic knee wall.

Knee walls are the bane of energy and comfort in homes by which i mean they are vertical half height walls built to convert normally unconditioned attic into liveable space. I have a room with a vaulted ceiling. Until recent building code changes these walls have essentially been insulated the same way since the beginning and are. I would like to insulate this gable wall against the attic.

When i accessed the knee wall attic i discovered that both the roof deck and the knee walls were insulated with fiberglass batts. The interior gable wall obviously extends to the ridge. The green curmudgeon wrote another article on poorly installed batts recently with photos of knauf fiberglass. Speaking of fiberglass batt insulation carl seville a k a.

They are 2 4 construction kraft faced r 11 batts in the wall with the paper facing the drywall and a plastic vapor barrier in the knee wall attic. In tight attics or odd shaped wall conditions i e. They are present in most any home that has ceilings of different heights. Rake walls it s easier to handle than plywood or thermo ply and still gives you an r 19 r121 assembly.

Kneewalls short walls under sloped ceilings are common in story and a half homes and in bonus rooms above garages. The knee wall cavities were filled with unfaced r13 batts and the roof rafters were filled with r19 faced batts although several of the batts had come unattached and are lying on the floor of the knee wall. I need a way to hold batt insulation in the stud bay so they do not fall out into the attic. If i place vertical runs of r 30 unfaced against the current plastic barrier i d use a perforated barrier to hold them in place.

A knee wall is generally referred to any vertical wall between the conditioned space and an attic. Rather than being a bully like guardian did to me a couple of years ago they commented on the article and asked for a dialogue on how to get better installation in the. Install an air barrier on the exterior of attic knee wall insulation and to block open floor joist cavities under attic knee walls. Install a top and bottom plate or blocking at the top and bottom of all knee wall cavities.

Case study attic knee walls in littleton. Finish interior of knee wall. Install insulation without misalignments compressions gaps or voids in all knee wall cavities. Then cover that same area with an r 8 fsk affixing it using cap nails.

Although kneewalls can help turn attics into living space they often present insulation challenges most builders install fiberglass batts between the studs and some type of blown insulation between the floor joists.