What is a knee wall in construction?

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.

What is the difference between a knee wall and a pony 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.

What is considered a knee wall?

The knee wall definition is a short wall, usually just shy of 3-feet-tall, that supports the rafters in your attic. They are usually found in older homes where the ceiling on the top floor is an attic. For example, the ceiling is the underside of the roof and slopes down on the sides.

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.

Why is it called a knee wall?

The term is derived from the association with a human knee, partly bent. Knee walls are common in houses in which the ceiling on the top floor is an attic, i.e. the ceiling is the underside of the roof and slopes down on one or more sides.

Building an Attic Knee Wall

How thick is a knee wall?

Home builders usually build 2×4 kneewalls that are 3.5″ thick.

Can you remove a knee wall?

If there is, that wall is probably a load-bearing wall, making the knee wall load bearing. It should not be removed, unless it is done so to replace it. In that case, temporary support of the rafters should be installed, before removing the knee wall.

What is the difference between a knee wall and a purlin?

Think of knee walls as small bearing walls supporting rafters. Purlins are 2 by 4s or 2 by 6s, typically. The purlin should be the same size as the rafter, at least. Think of purlins as small beams that run under the midpoint of all the rafters.

What height should a knee wall be?

Knee walls are often referred to as a half-wall or partition wall. They extend from the floor to a height of approximately 3 feet (91.44 cm) and are often constructed around or up against a shower stall or bathtub surround. Knee walls are generally an extension of the side of a bathtub or shower and can be tiled over.

Why do you need a knee wall?

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.

What do you call a wall that doesn't reach the ceiling?

For all intents, a pony wall is just a short wall that does not reach the ceiling; it need not be any particular height nor width, though it typically reaches about 3 feet tall.

Do knee walls support rafters?

Roof rafters must be supported by bracing (kickers) or kneewalls unless the rafters are sized to span from eaves to ridge and their ends are prevented from spreading by proper connection to continuous (or lap-spliced) ceiling joists.

What is the bottom half of a wall called?

In architecture, a baseboard (also called skirting board, skirting, wainscoting, mopboard, floor molding, or base molding) is usually wooden or vinyl board covering the lowest part of an interior wall.

Are half walls outdated?

Pony walls were famous back in the 1960s, so some people may think they've gone out of style by now. But believe it or not, these short, usually non-weight-bearing walls may have lots of useful and aesthetic purposes around your house. Pony walls are actually coming back in style in some home designs.

What is a knee wall in basement?

An engineered knee wall (sometimes called a pony wall) is a poured concrete wall that is installed on the interior side of a foundation in a basement or cellar, in effect making the wall of the foundation twice as thick.

What is code height for a half wall?

A half wall, also called a knee wall or pony wall, differs from a regular wall in height alone. Technically, a half wall can be any height short of the ceiling; realistically, pony wall height is usually about 3 to 4 feet tall, depending on the wall's purpose and location.

Can half walls be load bearing?

Is a Partial Wall Load-Bearing? If the wall is a partial wall, meaning it stops short of an adjacent wall, it may or may not be load-bearing. For example, the builder may have installed a microlam beam to span across the opening and carry the load above.

What is knee wall in attic?

An attic knee wall is a vertical separation between attic space on one side and conditioned space on the other side.

What is code for a knee wall?

Looking at the code book (section 305.1) is states that the minimum habitable area of any room must be a minimum of 120 square feet. Furthermore, the minimum ceiling height has to be 7' unless there is a sloped ceiling in which case the minimum height of the knee wall is 5'in order to count towards the 120 sq.

How do you insulate a knee wall?

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.

What is the top of a half wall called?

The top of a pony wall is often finished with a wood cap. Usually, this cap overhangs the wall by an inch or so to create enough space to run molding to hide the joint. Used this way, pony walls are a great way to separate spaces while preserving long, interior views that make both areas feel larger.