Written by: Luke Cheverie
Reviewer: Editorial Team
Casement, awning and hopper windows differ in one key way, how they open. That single detail decides how much air comes in, where you can place each window, and which room each style belongs in.
Here’s how each one works and what it does well.
Looking for casement windows on their own? Read what is a casement window to learn the benefits and maintenance tips.
Planning a basement bedroom? Read our guide to egress window styles and learn about what's important for building code.
The quick answer
If you’re short on time, here is what you need to know.
A casement hinges on the side and opens with a crank, so it swings fully open to catch the breeze and gives you an unobstructed view. Closed, it seals tight against the frame, which makes it the most airtight of the three. That makes it a natural fit for living rooms, bedrooms, and most of the house.
An awning hinges at the top and opens outward from the bottom, so you can leave it open during a light rain without water coming in. It’s a good fit for high, wide, or short openings, and for spots like a bathroom or above a kitchen counter.
A hopper tilts into the room and locks partly open for ventilation or fully open for what's known as egress. A common window term that means “escape window” in an emergency. That makes it the right choice for basement openings, where a safe way out in an emergency matters.
What about efficiency? Casement and awning are within a point of each other: ER 40 and ER 39 on double-pane, and tied at ER 48 on triple-pane. Between casement and awning, let function make the call, since the numbers are nearly identical. Hopper windows rate a little lower on double-pane, at ER 35, but the hopper’s main draw is egress (its sash locks fully open at 90 degrees), plus an ER 35 is still energy efficient.
What’s a “crank window”? Usually a casement. Awnings are cranked too, but the term is most closely tied to casements.
Casement vs. awning: the core difference
A casement window is hinged on the side and swings out like a door. An awning window is hinged at the top and swings out from the bottom.
How each one opens (and why the hinge changes everything)
Both styles open outward with a crank, so you never have to push a frame up or slide it sideways. Simply turn the handle and the window opens. Turn it back, it closes and locks tight against the frame.
Since the sash swings outward, the screen lives on the inside, so you can open, close and operate these windows without ever touching it. That also makes cleaning easier. With the sash open, you can reach the outside of the glass from indoors, and when the screen itself needs a wipe, it comes out with one click.
Airflow: which one actually moves more air
Casement wins on airflow, and it isn't close. The whole side of the sash opens, and the angled glass catches breezes moving along your wall and steers it inside. It's the reason at Nordik we describe our RevoCell® casements as the window that gives maximum ventilation when open.
An awning opens only along the bottom edge, at an angle. You get steady, gentle airflow, but not a big breeze. The trade-off is the good part, that top-hinged sash keeps a light summer shower out while the window stays open. If you’re dealing with July humidity, a passing storm, a stuffy bathroom, the awning keeps things breathing while the casement has to close up.
Where hopper windows fit
A hopper is considered the ‘basement specialist’, and the reason comes down to safety. It swings inward, tilting into the room instead of out into the yard, so it never bumps into the window well or the wall outside and can give you a clear exit in case of an emergency.
Hopper vs. awning: same shape, opposite direction
Picture an awning window, then flip the direction. An awning swings outward and is opened with a crank. A hopper opens inward and is operated by hand with a turn-handle lock, no crank required. Same short, wide shape, but move in the opposite direction.
Why hoppers belong in basements
Below grade, there's rarely ever room for a sash to swing outside. A hopper keeps all its movement on your side of the wall. The RevoCell® hopper adds two positions that matter down there:
45° and locked: the sash holds partly open for ventilation, so a damp basement can breathe.
90° and locked: the sash holds fully open for egress, a real exit in case you ever need one.
The sash is also fully removable, which makes cleaning simple and clears the opening for egress.
Egress and building code
If you’re finishing a basement, adding a bedroom or creating a second suite, this is the part to get right. Ontario’s building code generally requires a bedroom window you can open from the inside, without tools, as a way out in an emergency. In a fire that blocks the stairs, that window is the exit.
That’s exactly what the RevoCell® hopper is built for. Its sash locks fully open at 90° and lifts out completely, clearing the opening for a safe escape. Building code requirements can vary from region to region, however our Hopper window satisfies the majority of Ontario’s code requirements outside of special circumstances. We recommend checking your code requirements before you commit to a window basement installation.
With more homeowners turning basements into family rooms and income suites, getting this right early saves a failed inspection later.
What to watch out for
Every window style comes with trade-offs. Knowing them before install day means no surprises once your new windows are in. Most window guides skip this part, but we’d rather you hear it from us now than find out for yourself later.
Casement windows
The sash swings into your space outside. Open next to a deck, a walkway or a side path, it can get in the way. You’ll need to plan where it opens.
Like any open window, it needs closing when the weather turns. If a storm rolls in out of nowhere, you’ll want to crank it shut. Once it’s closed, you’re in good shape: our casements rate very well for air leakage.
The crank is a moving part. Operators and hinges take daily use, so it can get worn over time. That's exactly why Nordik casements run on a heavy-duty dual-arm operator on larger sashes, and why our 25-year warranty also covers the hardware.
Very wide openings don't suit it. A casement wants to be taller than it is wide. For a wide wall, you’ll want to pair your casement with a picture window to make the most of the space.
Awning windows
Less airflow than a casement of the same size. It opens only along the bottom, so you get a gentle draft instead of maximum airflow.
Placement matters outside. An open awning sash sticks out from the wall like a casement, so placing one beside a walkway or low on a deck wall can put it in the way of passersby.
The outside of the glass collects drips and debris because it angles out under the elements, especially under trees. Depending on usage, regular cleaning may be required.
Hopper windows
It opens into your room. Curtains, blinds and that shelf you love need clearance.
It's not a rainy-day window. The open top can let water in, so close it when the weather turns.
It's really only for the basement. Main use for below grade as an emergency exit. An Awning or casement is more energy efficient but this window is more about satisfying the basement element and Ontario code.
Which style goes in which room
Every room asks something different from its window. Some need fresh air, some need easy operation, and some just need light. Picking the right style for each space is what makes the whole house work better.
The bottom line
Casement, awning or hopper, there's no single "best" window, only the best one for each room. Casements belong almost everywhere, awnings earn their spot in bathrooms and short, wide openings, and hoppers are the basement go-to for safety reasons. With efficiency essentially tied between casement and awning, you can choose on how each room actually gets used.
Not sure which goes where in your home? That's exactly what a no-pressure consultation is for.
Frequently Asked Questions
What is the difference between casement and awning windows?
A casement is hinged on the side and swings out like a door. An awning is hinged at the top and swings out from the bottom. Casements give more airflow; awnings can stay open in light rain.
Which gives better airflow, casement or awning?
Casement. The full side of the sash opens and the angled glass catches passing breezes. An awning opens only along the bottom edge, so airflow is gentler.
What are common problems with casement windows?
The most common complaints are a sash that swings into a walkway, rain getting in when it's left open, and worn crank hardware on older or lower-quality windows. A heavy-duty operator and a warranty that covers parts and labour take care of the last one.
Can awning windows stay open in the rain?
Yes, in light rain. The top-hinged sash acts like a small roof over the opening. In wind-driven storms, close it.
Which window is best for a basement?
For a small, high opening, a hopper window is best. It swings outward into the window well. For a basement bedroom or rental suite, choose a hopper.
Do casement or awning windows seal better in winter?
Both seal very well because the sash locks tight against the frame. On RevoCell® windows, the casement tests slightly tighter on air leakage (0.02 vs. 0.08 l/s·m²), and the two tie on triple-pane Energy Rating at 48.
Which windows can be used as egress windows?
Hoppers are the most common egress window. A casement can also work, however, it runs into trouble with its outward swing. Awnings rarely qualify because the open sash blocks the opening. In Ontario, the opening must be at least 0.35 m² with no side under 380 mm.
Is a crank window the same as a casement?
Usually. "Crank-out window" almost always means a casement, though awnings use a crank too.