Window Trim Styles | Interior & Exterior Casing Guide for BC Homes | SilverLine Exteriors

Every window that leaves our Port Coquitlam shop gets finished on site with trim, and after nearly 20 years of installs across Metro Vancouver we can tell you the local pattern: most homes built before 1990 have narrow colonial casing inside and rotting wood brick mould outside, and almost everyone replacing their windows upgrades both. This guide covers the window trim styles we see and install every week, what each one costs to get right, and which materials survive our wet coastal climate.

If you are choosing trim as part of a window replacement, the good news is that new trim is normally built into the install quote. A new double glazed vinyl window runs $800 to $1,000 installed, and triple glazed runs $1,000 to $1,400. Trim decisions rarely change that number by much, so pick the style you want rather than the one you think you can afford.

What window trim is (and what each piece is called)

Window trim is the finish material that covers the gap between the window frame and the wall. Without it you would see shims, spray foam, and rough framing around every opening. Trim closes that joint, sheds water on the exterior, and gives the window its finished look inside.

A full interior trim package has four parts:

• Head casing, the horizontal piece across the top of the window
• Side casings, the vertical pieces on the left and right
• Stool, the flat “shelf” at the bottom that most people call the sill
• Apron, the short piece of trim mounted under the stool

On the exterior, the sill is the sloped piece at the bottom that directs rain away from the wall, and brick mould is the traditional thick casing profile you see on older homes. Standard casing runs 2.5 to 3.5 inches wide. Wider than that and you are into craftsman or colonial territory, which we will get to below.

Interior window trim styles

Inside the house, trim is mostly a design decision. These are the interior window trim styles that come up in our quotes, roughly in order of how often Metro Vancouver homeowners pick them.

Modern flat casing

Flat, smooth boards with square edges, usually 2.5 to 3 inches wide, mitred at the corners. No profile, no ornament. This is the default in new construction across the Lower Mainland and the most common choice when we replace windows in townhomes and condos. It suits the clean lines of vinyl windows and it is the cheapest style to install because there are no layered pieces.

Craftsman trim

Craftsman window trim uses thicker flat stock, typically 3.5 inches or wider on the sides with a heavier head casing across the top, butt-jointed rather than mitred. Vancouver has entire neighbourhoods of original craftsman homes, and in areas like New Westminster’s Queens Park or East Vancouver’s older blocks this style is the natural match. It costs more than flat casing because the header is built up from two or four separate pieces.

Colonial casing

The curved, stepped profile you will find in most Metro Vancouver homes built from the 1960s through the 1990s. It is 2.25 to 3.5 inches wide with a moulded face. If you own a Vancouver Special or an 80s rancher, this is almost certainly what is around your windows right now. Plenty of homeowners keep it for consistency with their doors and baseboards. Just as many use a window replacement as the excuse to switch to flat casing.

Shaker and farmhouse trim

Simple flat boards like modern casing but wider, with a stool and apron at the bottom and sometimes a slightly proud head casing. Painted white, it reads as farmhouse. The difference from craftsman is weight: shaker trim skips the built-up header.

Drywall return (no trim)

Some contemporary builds skip casing entirely and wrap the drywall into the window opening with a metal corner bead. It looks minimal and saves material, but the joint tends to crack as the house moves, and there is no wood to absorb the knocks a windowsill takes. We install windows into drywall-return openings regularly and they perform fine. Just know that repairs mean a drywaller, not a five minute caulk touch-up.

Exterior window trim styles

Outside is where trim stops being decoration and starts being weather protection. Metro Vancouver gets roughly 1,200 mm of rain a year on the coast and more as you move up the North Shore, so exterior trim here has one job before any styling: keep water out of the wall.

Flat stock trim

Flat boards, usually 3.5 inches wide, surrounding the window on all four sides over the siding or integrated with it. This is the standard on Hardie-clad homes and the style we install most. In fiber cement it will not rot, and painted a contrasting colour it frames the window sharply against the siding.

Brick mould

The traditional rounded casing profile, about 2 inches wide, that surrounds windows on most homes built before the 1990s. Original brick mould in this region is wood, and wood brick mould in a Vancouver winter is a maintenance item: it needs paint every few years and it rots from the bottom corners up. When we replace windows on older homes we usually replace wood brick mould with PVC or aluminum-capped versions that keep the traditional look without the upkeep.

Craftsman surround

Wide side boards, a thick header with a drip cap, and a sloped sill below. On heritage-style homes with cedar or Hardie siding this is the style that looks correct, and it pairs naturally with board and batten or lap siding gables.

Aluminum-capped trim

Existing wood trim wrapped in custom-bent aluminum flashing. Capping is common on window replacements because it seals old wood brick mould without the cost of tearing it off, and it never needs paint. The bends are made on site with a brake, so the profile follows whatever trim is already there. We cap trim on a large share of our retrofit window installs across Burnaby, Coquitlam, and Surrey.

Contrast trim

Less a profile than a colour strategy: white windows with dark trim, or black windows with white trim. Black window frames have been the strongest trend we have seen in our own order book over the last five years, and crisp white flat stock around them is the pairing most customers choose.

Trim materials: what survives BC weather

Style gets the attention, but material is the decision that determines whether your trim looks good in ten years. Here is how the common options compare for our climate.

For a deeper look at fiber cement trim boards specifically, our Hardie Trim guide covers board sizes, colour options, and how the boards tie into siding.

What trim work costs in Metro Vancouver

Trim pricing depends on how the work is packaged, and this is where homeowners get surprised by quotes.

Bundled with window replacement, interior casing and exterior capping or brick mould replacement are typically part of the installed price. That $800 to $1,000 per double glazed window includes finishing the opening properly on both sides. This is the cheapest way to update trim because the crew is already set up on site.

Bundled with siding, exterior trim is quoted as part of the whole envelope. On a Hardie job running $9 to $15 per square foot installed, window surrounds are line items within that scope, and it is the right time to switch styles since everything comes off the wall anyway.

As a standalone project, trim replacement gets expensive per window because a crew still has to mobilize for a small scope. If your trim is failing, it is worth asking whether the windows behind it are on their way out too. Twenty year old windows with rotting brick mould usually mean one combined project makes more sense than two separate ones. Our window replacement cost guide breaks down current Vancouver pricing by window type.

What happens to your trim during a window replacement

This is the question behind most trim questions we get, so here is the honest version from the crew’s side.

In a retrofit install, the new window goes into the existing frame. Interior casing usually stays, and the exterior gets new brick mould or aluminum capping. Your interior paint lines survive. This is the least disruptive path and the most common one for occupied homes.

In a full frame replacement, everything comes out down to the rough opening: window, frame, interior casing, exterior trim. You get new flashing and insulation around the opening and complete freedom to change trim styles, because everything is being rebuilt anyway. If your home still has original single pane aluminum windows, this is normally the right call.

Either way, ask your installer two questions: who is painting the new interior casing, and is the exterior trim being flashed or just caulked. Caulk alone is not a long term water strategy in this climate. Every exterior trim detail we install is designed to shed water first and look good second, which is the order the rain forecast demands.

Matching trim to Metro Vancouver housing stock

A quick cheat sheet based on the homes we actually work on, from our shop on Broadway Street in Port Coquitlam out across the Lower Mainland:

• Vancouver Special (1965 to 1985): colonial casing inside, minimal stucco returns outside. Flat modern casing is the standard upgrade, and white or black flat stock sharpens the exterior.
• 1980s and 90s ranchers and split levels in Coquitlam, Surrey, and Langley: wood brick mould that is usually failing. Replace with PVC brick mould or cap in aluminum during window replacement.
• Craftsman and heritage homes in New Westminster and East Van: wide craftsman surrounds with a proper drip cap. Fiber cement gives the period look without cedar maintenance.
• Townhomes and strata buildings: trim changes usually need council approval and consistency across units, so most strata work is like-for-like replacement in more durable materials.
• New builds and contemporary homes: flat stock exteriors and either flat casing or drywall returns inside.

Trim also has to suit the window itself. A picture window carries wide craftsman surrounds well, while a small basement slider looks overdressed in anything beyond flat casing. Our window styles guide covers how the window shapes themselves change the look.

Frequently asked questions

What are the different styles of window trim?

The main interior styles are modern flat casing, craftsman, colonial, shaker or farmhouse, and the trimless drywall return. Exterior styles are flat stock, brick mould, craftsman surrounds, and aluminum-capped trim. Most Metro Vancouver homes have colonial casing inside and brick mould outside unless they have been renovated.

What type of trim is best for windows?

Inside, painted MDF or finger-jointed pine in whatever profile matches your home. Outside in the Lower Mainland, the best performers are fiber cement, PVC, and aluminum-capped trim, because untreated wood does not last in coastal BC rain. The best style is the one that matches your home’s era; the best material is the one that does not rot.

What kind of window trim is popular now?

Flat and simple. Modern flat casing dominates interior requests, and on exteriors the strongest current trend in our order book is black window frames with clean white or monochrome flat stock trim. Ornate layered profiles have mostly disappeared from new work except on heritage restorations.

What are the different types of window sill trim?

Interior windows use a stool (the flat shelf) with an apron beneath it, or a picture frame casing with no stool at all. Exterior windows use a sloped sill, in wood, PVC, fiber cement, or bent aluminum, angled so rain drains away from the wall. The slope matters more than the material: a flat exterior sill will pool water against your window frame.

Do new windows come with new trim?

Usually, but confirm the scope. Our window replacement quotes include finishing the exterior with new brick mould or capping and re-trimming or preserving the interior casing. Some low quotes exclude trim entirely, which is one reason two window quotes can be hundreds of dollars apart for the same opening.

Can I change my trim style without replacing my windows?

Yes. Interior casing swaps are straightforward carpentry. Exterior trim can be replaced or capped on its own, though if your windows are older it is worth pricing the combined job, since mobilizing a crew twice costs more than doing it once.

Talk to the people who build the windows

SilverLine has manufactured windows in Port Coquitlam and installed them across Metro Vancouver since 2007. We have 9 HomeStars awards, a BBB A+ rating, and 107 Google reviews at 4.5 stars, and our crews trim out every window we install, inside and outside. If you are planning a window replacement and want the trim done right for this climate, call us at 604-942-0488 or request a free quote. We will tell you which style suits your house and which materials will still look sharp when the windows are due for their next upgrade.