Front and Entrance Doors
by SimonPublished: September 2, 2026 | Updated: September 24, 2026Doors7 min read

A front entrance is rarely just a door. Add a narrow glazed panel each side and a horizontal pane above, and you have specified an assembly wider than the opening you started with, brighter than a solid leaf, and different again in the way it holds heat. The choices get easier once you know what each part is called.

Table of Contents

Key Takeaways

  • A sidelight is a fixed narrow glazed panel beside the door leaf. A highlight, also called a toplight, sits above the door.
  • Australian entrance leaves are commonly 820mm, 870mm, 920mm or 1020mm wide. Sidelights usually run 300mm to 500mm.
  • Each sidelight adds its width plus a mullion, so a leaf with two sidelights often needs an opening near 1800mm.
  • Widening an opening in a load bearing wall brings lintel sizing into the job, so decide at design stage.
  • Glass loses more heat than an insulated leaf, so glazing and frame material matter as glazed area grows.
  • Obscure glazing protects a hallway from the street, and laminated glass beside a lock is worth specifying.

What Sidelights and Highlights Are

Australian architects, suppliers and building surveyors use a settled set of terms for an entrance, and matching them saves confusion when you brief a maker of double glazed windows and doors.

Sidelights

A sidelight is a fixed glazed panel set vertically beside the door leaf, inside the same frame, separated from it by a mullion. It does not open. Sidelights can be full height, or split by a rail so only the upper section is glazed.

Highlights and Toplights

A highlight is the horizontal glazed panel above the door, separated from it by a transom. Toplight means the same thing in Australia. Most are fixed, though awning versions exist where ventilation above head height is wanted. They suit high ceilings, where a standard 2040mm door leaves an awkward gap.

American Term Equivalents

Much of the material online is written for the United States, where a highlight is a transom or transom light and sidelight is spelled sidelite. American listings also grade the glass in the leaf as half lite, three quarter lite or full lite. Only the labels differ.

Common Entrance Door Configurations

Five arrangements cover almost every residential entrance, and each changes the opening width, the light and the cost.

Single Leaf Alone

One door in a plain frame. The narrowest option and the simplest structurally, with any glazing inside the leaf.

Single Leaf With One Sidelight

Glass on one side only. This suits an entrance close to a corner or wall return with no room for symmetry, and it puts the light where the hallway runs.

Single Leaf With Two Sidelights

The symmetrical entry most people picture. It reads as a wide, formal opening while using a normal sized door, and most often triggers structural work.

Double Leaf Entrances

Two leaves meeting in the middle, usually with one held shut by flush bolts. This gives a genuinely wide clear opening, at the cost of a heavier frame and a wider span above.

Highlights Above Any Configuration

A highlight can sit above any of the four arrangements. It adds height rather than width, so it rarely changes the lintel calculation, but it does raise the head of the opening.

Working Out Opening Width

The width that matters is not the door. It is the structural opening the builder has to leave in the wall.

Typical Leaf Widths

Entrance leaves are commonly 820mm, 870mm, 920mm or 1020mm wide and 2040mm high, with 2340mm and 2400mm available where ceilings allow. Larger leaves get heavy, so hinge specification tightens as size grows.

Typical Sidelight Widths

Sidelights generally sit between 300mm and 500mm of glass width. Below about 250mm they read as a slot. Above about 600mm they compete with the door, which is usually where a double leaf makes more sense.

Total Structural Opening

Add the leaf, each sidelight, the mullions between them and the outer frame. As a working figure, an 870mm leaf with two 400mm sidelights lands near 1800mm of structural opening once frame and mullion allowances are counted, and a double leaf with two sidelights can approach 2600mm. Allowances vary, so confirm them before framing, because ranges of double glazed entrance door systems carry their own frame depths and mullion dimensions.

Structural and Lintel Implications

Once an opening in a load bearing wall goes beyond a standard doorway, the wall above has to be carried by a lintel sized for its span and load. A single door opening is routine. An opening near 1800mm is not, and one near 2600mm usually calls for an engineered timber or steel lintel. Residential timber framing spans are set out in AS 1684, and anything outside those tables needs a structural engineer.

The practical consequence is timing. Two sidelights chosen while the frame is on paper cost nothing extra in structure. The same two chosen after the wall is up mean propping, a new lintel and repairs to both faces.

Glazing Privacy and Light

Sidelights sit at eye level beside a door that opens onto a hallway, so the glass specification does more work here than in most windows.

Obscure and Textured Glass

Acid etched, satin, sandblasted and reeded glass all pass light while breaking up the view. Reeded glass distorts at close range while still reading as clear from the street. A split sidelight, obscure below and clear above, keeps the hallway private and still lets you see who is at the door.

Laminated and Security Glass

Glazing in and beside a door is a safety glazing location under AS 1288, so it will be toughened or laminated. Laminated suits the sidelight nearest the lock, since it holds together when broken and makes reaching through to a deadlock far harder. In a double glazed unit the laminated pane can be the inner one.

The Thermal Trade Off

Every sidelight and highlight replaces insulated door core with glass, and glass conducts heat more readily. A door with two sidelights and a highlight can easily triple the glazed area of the entry. That matters most at a front door, which may be shaded, north facing or west facing depending on how your home is oriented, and which opens onto a hallway feeding the rest of the house.

The trade off is manageable rather than disqualifying. Double glazed units with a low emissivity coating, an argon fill and a warm edge spacer bring the glazed sections much closer to the leaf, and a frame that does not conduct heat straight through does the rest. That is where uPVC earns its place, since it insulates without the thermal bridge of an untreated aluminium frame. Well specified double glazed front doors with matching sidelight and highlight units keep the light without giving back the comfort.

Entry glazing also counts in a home’s energy assessment, so a large glazed entrance changes the numbers the rest of the design works with.

FAQs

Is a highlight the same as a transom window?

Yes. Transom or transom light is the American term for a highlight or toplight. The transom itself is the horizontal member separating the door from the panel above.

Do sidelights make a front door less secure?

Not inherently, provided glazing and locking are specified together. Laminated glass in the panel nearest the lock, plus multi point locking, addresses the reach through risk plain glass beside a handle creates.

Will adding sidelights and a highlight make my entry colder?

It can if the glazing is single glazed or the frame conducts heat. With double glazed units and an insulating frame, the difference against a solid door is small enough that most people notice the extra light rather than the temperature.

Can I add sidelights to an existing front door?

Sometimes, though it means widening the opening, which brings in lintel work if the wall is load bearing. Replacing the entrance as one unit is generally cleaner than grafting panels onto an existing frame.

Getting the Specification Right

Sidelights and highlights are a specification decision dressed as a style decision. The configuration sets the structural opening, the lintel, the amount of hallway visible from the footpath and the thermal behaviour of the coldest part of the facade. Decide the arrangement early, put real dimensions against it, and match the glazing to the amount of glass you have committed to.

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Simon

Simon is part of the Double Glazing Melbourne team, working with homeowners across Victoria to improve comfort, energy efficiency, and noise reduction through double glazed windows and doors. He supports clients in finding suitable uPVC window and door solutions based on their property, preferences, and local conditions. Simon focuses on practical outcomes, helping homeowners feel more confident about their choices when upgrading or replacing existing windows and doors.