Interior Door Installation

Slab or pre-hung

There are two ways to replace an interior door and the right choice depends on the condition of the existing jamb.

A slab replacement reuses the existing jamb and hardware locations. The new door is cut to size, mortised for hinges, bored for the handle set and hung. It is less disruptive, keeps the existing casing intact, and is the right call when the jamb is square, undamaged and the casing is staying.

A pre-hung door arrives already hung in a new jamb. The old jamb and casing come out, the new unit is set plumb and level in the rough opening, shimmed and fastened, then re-cased. It costs more and creates more work, but it is the only real option when the existing jamb is damaged, badly out of plumb, or when the casing is being upgraded anyway.

In practice, on a whole-house door replacement where trim is also being upgraded, pre-hung is usually the better value despite the higher unit cost — because the labour to make old jambs work well can exceed the saving.

Door types we install

Hinged interior doors

The standard swing door in solid-core or hollow-core. Solid-core costs more and is dramatically better for sound isolation — worth it for bedrooms, bathrooms and home offices.

Barn doors

Surface-mounted on a track. Useful where a swing door has nowhere to go. They do not seal, so they are poor for bathrooms and any room needing sound privacy. The track needs solid backing across its full span.

Pocket doors

Slide into a wall cavity, saving the full swing area. Excellent where space is tight, but installation requires opening the wall and the cavity cannot contain services or be a load-bearing element without engineering.

Double and French doors

Paired doors for a wide opening. Alignment between the two leaves is the demanding part.

Bifold and closet doors

Folding or sliding closet closures. Often the cheapest visible element in a house and one of the easiest to upgrade.

Cased openings

Removing a door entirely and finishing the opening with jamb and casing. Frequently the best answer for doorways that never get closed.

Why interior doors bind in Calgary homes

A door that closed cleanly in October and sticks in February is one of the most common calls we get, and it is almost never the door's fault. Two things drive it. Solid wood doors shrink and swell with humidity, and Calgary's indoor air routinely drops below 20% relative humidity in winter with forced-air heating — a swing wide enough to move a door several millimetres across its width. Separately, houses settle, and an opening that racks even slightly puts the door and the frame out of parallel.

The diagnosis is worth doing before anything is planed. If the binding is seasonal and moves around the door edge through the year, it is humidity, and the answer is usually adjusting the strike and hinges rather than removing material — wood taken off in February leaves a gap in July. If the binding is consistent and the gap around the door is visibly tapered, the opening has moved and the frame needs re-shimming or the door re-hung to match.

For new installations, the single biggest determinant of a door that works for decades is whether the frame is set plumb and square in an opening that is neither. Rough openings in Calgary homes are frequently out by several millimetres. Shimming a frame properly takes time, and it is the difference between a door that swings and stays where you leave it and one that drifts open or closed on its own.

Interior door types compared

What a proper door installation includes

Checking the opening

Plumb, level and square measured before anything is fitted. The numbers determine how the frame is shimmed.

Shimming behind every hinge

Solid bearing at each hinge point. Without it the frame flexes and the door drops over time.

Consistent reveal

An even gap around the door — typically 3mm at the sides and top. Inconsistency here is the most visible sign of a rushed hang.

Correct hinge count for the weight

Solid-core and solid wood doors need three hinges, and heavier doors need heavier hinges. Two hinges on a solid door will sag.

Strike plate fitted to the actual latch position

Marked from the closed door rather than measured nominally, so the latch engages without being forced.

Casing scribed where the wall is not flat

So the casing sits tight against the wall rather than showing a shadow gap along one edge.

Request a whole-home door package

For several rooms, label each opening on a simple plan and photograph both sides. Record whether you want to keep the existing jamb and casing or replace the complete pre-hung assembly. A proposal for slabs alone is not comparable to one including jambs, casing, hinges, handles, painting and disposal.

Mention finished-floor changes before ordering. A new threshold or different floor thickness can affect door clearance and reveal problems in an older opening. Ask the installer to confirm handing on site rather than relying on “left” and “right” in an email. For double doors and closets, show the adjacent furniture and swing space.

Garage-to-house doors, fire-rated assemblies and changes to an opening need separate assessment. Do not substitute a decorative interior door where another assembly is required. The contractor should confirm the applicable product and installation requirements before a quote is approved.

Calgary Carpentry prioritizes suitable larger projects; a single small repair may not match an available contractor. Include the total opening count and any related trim work in your request. Scope fit, availability and pricing are confirmed after review.