What type of insulation is used for knee walls?
If you are using air-permeable insulation (fiberglass, cellulose cellulose, or mineral wool), it’s essential to include an air barrier on the back side of the kneewall. The best material for this purpose is rigid foam; acceptable alternatives include OSB, ThermoPly, or drywall.
What is the function of a knee wall in an attic?
A knee wall is a short vertical wall, roughly two or three feet high, thats used to support rafters in the roof. It also blocks off the space that’s too small (due to the sloping roof) to use for anything in an attic.
How do you finish a knee wall in an attic?
Quote from the video:
Quote from Youtube video: Correct behind it okay right and people are using the knee wall space as storage. That's right that's about all you can use it for because. It's very small space right.
How do you insulate a knee wall space?
Knee Wall Insulation
The best materials for the attic, and thus the knee wall, are spray foam, fiberglass, and cellulose. If you plan to insulate the roof deck of your attic, then you would use spray foam or fiberglass batts. Cellulose is much better suited for the attic flat.
Should a knee wall be insulated?
The knee wall (and attic floor) in the attic space behind should be insulated to the recommended levels. You can also insulate and air seal the rafter space along the sloped ceiling of the knee wall space.
Do knee walls support rafters?
In his book A Visual Dictionary of Architecture, Francis D. K. Ching defines a knee wall as “a short wall supporting rafters at some intermediate position along their length.” The knee wall provides support to rafters which therefore need not be large enough to span from the ridge to the eaves.
Are knee walls load-bearing?
These low walls help define the living space by creating vertical surfaces between the sloping rafters and the finished floor. They’re typically framed with 2x4s and built 4-feet-high so they can easily be covered with full sheets of drywall. In most cases a knee wall is not a load-bearing partition.
Do knee walls provide structural support?
Knee walls aren’t technically required for a structurally sound home or building, but they do take some of the load off the rafters. If you live in an older home and are concerned about the roof’s stability, it might be a good idea to install them.
What is the difference between a pony wall and a knee wall?
Also known as half walls, pony walls only come up—you guessed it—halfway or partway to partially divide a space. Pony walls differ from knee walls, which are generally intended to support something such as a countertop, handrail, or rafter.
How do you insulate a half story?
Traditional. The traditional way to insulate and ventilate a one-and-one-half story home is to insulate right up against the first floor ceiling, the knee walls, the vaulted roof sections, and again at the second floor ceiling.
How do you insulate attic roof rafters?
Quote from the video:
Quote from Youtube video: Place the craft faced insulation. Down between the joists on top of the drywall. And with the facing down toward the interior of the house be careful not to compress the insulation.
Is it OK to insulate roof rafters?
Insulating between rafters will do no good, because the attic should be ventilated, and the rafter insulation would be between two unheated spaces. You can add insulation to the floor; the more the merrier. Just don’t put it in the eaves. Also, make sure the attic is well ventilated.
Can I insulate the underside of my roof?
Open-cell spray polyurethane foam or closed-cell spray polyurethane foam (ccSPF) insulation can be sprayed along the underside of the roof sheathing to provide a conditioned and insulated attic space that can be durable and efficient in all climate zones (see Figure 1).
Can you have too much insulation in your attic?
It’s possible to over-insulate an attic as too much will cause moisture buildup and eventually result in mold. Eventually, adding more insulation leads to diminishing returns in trapping heat as well.
Which is better attic insulation blown or rolled?
Rolled fiberglass insulation scores an R-value of 3.7. So overall, rolled fiberglass insulation is slightly more effective at blocking in and out heat than its blown counterpart.
How do I make my rafters deeper for insulation?
You can add additional insulation value by installing rigid foam insulation over the surface of the new rafters and batt insulation. Rigid foam insulation comes in 4-by-8 sheets and attaches in a method similar to installing drywall panels.
What happens if you have too much loft insulation?
The risk of ‘too much’ insulation in the loft is condensation within the insulation itself making it wet with resulting loss in effectiveness and possible staining/timber decay.
Does insulation need room to breathe?
Because insulation keeps the heat from the escaping, the temperature of the loft, for example, would naturally stay warm. Again, many would say that this is nothing but good news, but even a warm space needs the capability to breathe and ventilate.
What is the recommended depth of loft insulation?
between 250mm and 270mm
Current government recommendations are for loft insulation to achieve a depth of between 250mm and 270mm but some new properties are increasing their level of loft insulation to 300mm. Again, as long as the loft has adequate ventilation, this is fine.
