Basement Column Wrap and Cover Ideas

The simplest way to cover a lally column in a basement is to wrap it in a non-structural finish: a split column wrap kit, a square box of light framing and drywall, or wood trim that matches the room. Whatever you choose, the cover must stay a finish only. Don't screw, drill or weld into the column, and don't let the framing wedge against the beam or carry any load. In a house with a secondary suite, the columns supporting the floor between units have to be protected with 15.9 mm Type X gypsum board, so the cover is no longer just a style choice.

Most basement renovations end up with one or more steel posts standing in the middle of the new rec room. Here's how to hide or feature them without causing problems for the structure or the inspector.

Check the column before you cover it

A finished wrap hides the column for years, so the time to look at it is now. Before you build anything around a lally column or steel post, check that:

• It is a permanent column, not a temporary one. An adjustable telepost with a threaded screw at the top may have been put in as a temporary shore. Our post on whether adjustable steel columns can be permanent explains how to tell, and what the Ontario Building Code expects of them.
• The base is sound. Look for rust at the bottom where the column meets the slab, especially if the basement has ever flooded. Flaking steel or a column that has lost section needs attention before it disappears behind drywall.
• It is plumb and fastened. The top should be secured to the beam and the bottom should sit on a footing, not just the floor slab. The 2024 Ontario Building Code requires columns to be centrally located on a footing and securely fastened to the member they support. Our guide to basement column rules in the Ontario Building Code covers the details.
• There is no sign of movement. Cracks in the slab around the base, a gap at the top or a beam that has dropped next to the column are reasons to call a contractor or engineer, not to cover up.

If the column needs replacing anyway, do that first. See how to replace lally columns and when you should.

Rules for any column cover

These apply whichever look you go for:

1. Never fasten into the column. Drilling or screwing into a concrete-filled pipe column, or welding brackets onto a steel post, can weaken it and is outside what a finish trade should be doing. The cover is held by its own framing, by clamping around the column, or by fastening to the floor and ceiling framing.
2. Leave a small gap. Build the box slightly larger than the column so it slides over without forcing. This also keeps the framing from rubbing on the steel.
3. Don't load the beam or the column through the framing. The top of the box should stop at the ceiling finish or be fastened to the joists, not jammed up tight under the steel beam. Framing shouldn't share or redirect the column's load.
4. Protect wood at the slab. Under Article 9.23.2.3 of the 2024 OBC, wood framing that isn't pressure treated and sits on concrete in contact with the ground has to be separated from the concrete with at least 0.05 mm polyethylene or Type S roll roofing. A basement slab qualifies, so use a treated bottom plate or a strip of poly under the framing at the base.
5. Plan for inspection. A removable trim panel at the base, or simply knowing where each column is, makes it easier to check for rust after a leak.

Column cover ideas

Split column wrap kits

Pre-made wraps come in two halves or as a hinged sleeve that closes around a round column. They are made in PVC, cellular vinyl, fibreglass, MDF and paint-grade wood, with matching base and capital trim. They go on without touching the column structurally and are the quickest way to get a clean round or square look. Measure the column diameter and height, including the plates at each end, and choose a wrap with enough inside clearance for the base plate.

A square box with drywall

The most common basement finish is a square box framed with 38 mm (2x) lumber or light steel studs, sheathed with drywall and finished with corner bead. It blends with drywall ceilings and walls and can be built to any size. Light steel studs are handy here because they don't shrink or twist and they suit a damp basement. Add a baseboard to match the room.

Wood-trimmed and craftsman columns

A boxed column clad in paint-grade wood or MDF, with a wider plinth at the bottom and a moulded cap at the top, turns the post into a feature. This works well between a family room and a bar or kitchenette, especially if there are two or more columns in a line under the same beam.

Stone, brick or tile veneer

Thin stone or brick veneer panels and tile can be applied over a framed and sheathed box (cement board for tile). The veneer is attached to the box, never to the column. Keep the extra weight in mind: heavy veneer needs solid framing and a base that can carry it.

Rope, reclaimed wood and other wraps

Natural rope wrapped around the column, or reclaimed boards fixed to a framed box, suit an industrial or rustic room. Rope can usually be held at the top and bottom by trim without fastening into the steel.

Leave it exposed and paint it

A steel post in good condition can simply be cleaned and painted, which suits an industrial-style basement with an exposed steel beam. Clean off any rust, prime bare steel with a rust-inhibitive primer, and finish in a colour that matches the beam. Our guide to painting steel railings and stairs covers surface prep, and the same steps apply to a post.

Hiding a lally column in a wall

Often the neatest answer is to put the column inside a partition wall. Plan the wall layout so the column lands in the line of studs, then frame around it:

• Frame the wall with a stud on each side of the column and a small gap to the steel.
• Use a treated bottom plate, or poly under it, where it sits on the slab.
• Fasten the wall to the floor and the joists above, not to the column or to the steel beam's flanges unless the beam was detailed for it.
• If the column is wider than the stud depth, either bump the wall out at the column or use deeper studs for that section.

A wall can also run along a line of columns to separate a mechanical room or storage space from the finished area. This often costs less than boxing each column individually. If you'd rather lose a column altogether, that is a structural change with its own engineering and permit, covered in can you remove a lally column to open a basement.

Columns and fire protection in a two-unit house

If the basement is being finished as a secondary suite, or might become one, the cover has a code job to do. Sentence 9.10.8.3.(2) of the 2024 Ontario Building Code requires light-frame walls, columns and beams, as well as loadbearing steel elements, that support floors between dwelling units in a house with a secondary suite to be protected by at least 15.9 mm thick Type X gypsum board.

In practice that means:

• Box each column in Type X board on all sides.
• Box the steel beam the columns support in the same way, so the protection is continuous with the Type X ceiling.
• Tape the joints and seal around penetrations so the smoke-tight barrier isn't broken.

A decorative wrap kit, vinyl sleeve or wood trim on its own doesn't meet that requirement. You can still apply trim over the Type X board for appearance. Existing houses being converted may have compliance alternatives under Part 11, so confirm with your building department. Our post on whether steel beams in houses need fireproofing covers the full picture.

Getting a new steel post made

If your column is rusted, undersized or an adjustable post that was never meant to stay, it's worth replacing it before the room is finished. A new fixed steel post cut to the measured height, with base and cap plates welded on, gives a clean, square column that's easy to wrap. We fabricate HSS and steel posts for basements with plates welded on, and we can prime or galvanize to suit. Send us the height, the beam it supports and your drawings for a quote, and see our steel products for the full range.