Casement Window Replacement in Waltham, MA

Easy to Open, Sealed Tight

Can't reach the window over your kitchen sink? Fighting a stuck sash every spring? A casement window fixes both.

Top Sash installs casement windows from Marvin, ProVia, and Andersen in Waltham and across Greater Boston. Licensed, Lead-Safe certified, and most homes done in 1 to 2 days.

New Marvin Ultimate casement windows from the inside, Sudbury, MA
Marvin Ultimate casements, Sudbury, MA.
Construction SupervisorCSL CS-119052
Home Improvement ContractorHIC #208527
Lead-Safe CertifiedMA LR4694
Official ProVia DealerWindows & doors
5.0 Stars on GoogleFormerly VIVA Windows
Two white casement windows with crank handles below a half-round window, Lincoln, MA
Casement windows below a custom half-round window. Lincoln, MA project.

What is a casement window?

Casements are hinged on the side and open outward with a simple crank. Turn the handle and the whole window swings open. Close it and the sash presses into the frame for one of the tightest seals of any window style.

A casement window has one sash (the part that holds the glass) hinged on the left or right side. You open it with a crank, and it swings out like a door.

Why homeowners love them:

  • Easy to reach. Over a sink, behind a counter, or above a tub, a crank is easier than lifting a sash.

  • Tight seal. When you lock a casement, the sash squeezes against the weatherstripping. Less air leaks through than on sliding windows.

  • More fresh air. The whole window opens, not half. And the open sash catches side breezes and steers them inside.

  • Clear view. No meeting rail across the middle of the glass.

Where casements fit best

Kitchens, bathrooms, mid-century and contemporary homes, additions, and next to picture windows. Casements are also the side windows in many bay windows.

Where a double-hung is better

Traditional Colonials and Victorians where you want the original look. See our double-hung windows page.

Casements and bedroom safety

Bedrooms need an emergency escape opening under the Massachusetts building code. Because a casement opens all the way, a casement can often give you the escape opening you need in a smaller window than a double-hung, which only opens halfway. We check this on every bedroom window we replace.

The casement windows we install

Casement is a window style, not a product line, so you can get one in almost any series we carry. Here’s how the three brands break down.

3 collections

Marvin casements

  • Essential: Ultrex fiberglass inside and out (Ultrex is Marvin’s own fiberglass, which won’t rot, swell, or need paint). Marvin’s most affordable line.
  • Elevate: Ultrex fiberglass outside, wood inside you can stain or paint. Low-profile folding handle that won’t snag your blinds.
  • Ultimate: extruded aluminum outside, wood inside. Multi-point lock, and a wash mode hinge that lets you clean the outside glass from indoors. Also comes as push-out or French casements.

Official ProVia dealer

ProVia casements

  • Endure: our go-to. Welded vinyl frame and sash, ComforTech glass with Super Spacer warm-edge spacers, 13 glass packages including triple-pane, and a lifetime limited warranty that transfers to one future owner.
  • Aspect: mid-range all-vinyl with high energy efficiency.
  • Aeris: vinyl outside, wood-clad inside.

Andersen Certified Contractor

Andersen casements

  • 100 Series: Fibrex composite frame, low maintenance.
  • 400 Series: wood inside, Perma-Shield vinyl cladding outside. Can be up to 6 feet tall.
  • A-Series: wood inside, fiberglass and composite outside.
  • E-Series: Andersen’s most custom line, wood inside, with 50 standard exterior colors.

Already have Andersen casements? We can match them.

What do casement windows cost?

Casements usually cost more than double-hungs of the same size. They have more moving parts: the crank, hinges, and locks. Beyond that, every house is different, so we don’t post one-size-fits-all prices.

What moves the price

  • The size of each window and how many you’re doing
  • The brand and series
  • Insert vs. full-frame install (switching from a double-hung to a casement is full-frame)
  • What we find once the old window is out: rot or worn trim
  • Exterior color, grilles, and hardware finishes
  • Glass upgrades like triple-pane
  • The building permit

That’s why we come out and look before we quote. Then we match the window to your house, your expectations, and your budget.

Making it easier

0% APR18 months, 0% APR, $0 down through Synchrony (subject to credit approval).
$75Replacing single-pane windows? Ask about the $75-per-window Mass Save rebate.
PayWe also take cash, check, Zelle, and Venmo.

Casement vs. double-hung vs. awning

FeatureCasementDouble-hungAwning
How it opensSwings out sideways, crankSlides up and downSwings out from the bottom, crank
AirflowWhole window opensHalf the window opensPartial, works in rain
SealVery tightGoodVery tight
Best forKitchens, hard-to-reach spots, modern homesTraditional homesBasements, bathrooms, above other windows
Cleaning outside glassWash mode or reach-throughTilts inReach-through

Energy efficiency in Climate Zone 5

Casements are one of the most airtight window styles you can buy. That’s a big deal in Waltham’s Climate Zone 5 winters.

$101 to $583
a year saved by a typical home replacing single-pane windows, per Mass Save

The federal window tax credit ended December 31, 2025. Use Mass Save in 2026.

U-factor

How fast heat escapes. Lower is better. ENERGY STAR's Northern-zone standard is 0.22 or lower.

Low-E glass

A thin coating that reflects heat back inside.

Argon gas

A clear gas between the panes that slows heat loss.

Compression seal

The crank pulls the sash tight against the weatherstripping, so wind pushes it tighter, not looser.

New Marvin Ultimate casement window with grilles and the Marvin label still on the glass, Sudbury, MA
Marvin Ultimate casement, Sudbury, MA project.

“All timelines were met, the installation crew was courteous and efficient, and the installation went smoothly.”

★★★★★ Hugh C., Google review

Our casement installation process

  1. Free consultation

    We look at the room, talk about how you use the window, and show samples.

  2. Measure

    Each opening measured and checked for square.

  3. Order

    Custom-built windows, about 5 to 6 weeks.

  4. Permit

    We pull the building permit with the Waltham Building Department.

  5. Install

    Swapping a casement for a casement is often an insert install. Changing from a double-hung to a casement is a full-frame install, with flashing, a sill pan, and foam insulation. Lead-safe containment on any pre-1978 home.

  6. Walkthrough

    We show you the crank, locks, and how to clean the glass.

Casements in Greater Boston homes

You'll see casements all over Eastern Massachusetts: on the mid-century ranches and split-levels in Waltham, Newton, and Lexington, on contemporary homes out in Lincoln, Sudbury, and Concord, and in kitchen additions just about everywhere. Older Colonials and Victorians often get a casement over the kitchen sink, even when the rest of the house stays double-hung.

We work across Greater Boston, from Brookline and Cambridge out to Sudbury, Maynard, and Concord.

Why Top Sash

  • Licensed: Massachusetts CSL CS-119052, HIC #208527
  • Lead-Safe: LR4694 and EPA Lead-Safe Certified Firm NAT-F251059-1
  • Insured: general liability and workers' comp
  • Official ProVia dealer, Andersen Certified Contractor, and experienced Marvin installer
  • 10+ years of crew installation experience
  • 5.0 stars on Google (formerly VIVA Windows)

Project showcase

Three new white Marvin Ultimate casement windows with grilles on a gray-sided Sudbury, MA home
Marvin UltimateCasementSudbury, MA

Sudbury, MA: new Marvin Ultimate casements

New Marvin Ultimate replacement casement windows.

Casement windows topped with custom arched windows in a gable wall, Lincoln, MA
CasementCustom shapesLincoln, MA

Lincoln, MA: casements and custom shapes

This Lincoln, MA project included casements, 2-lite sliders, a patio door, custom shaped windows, and tilt-and-turn windows.

Dark-framed Andersen casement and picture windows with white trim on navy vertical siding
AndersenCasementPicture window

Andersen casements on a contemporary home

Dark-framed Andersen casement and picture windows with crisp white trim, set into navy vertical siding. Inside, the wide glass keeps the view open to the yard.

Casement window FAQs

How much do casement windows cost in Waltham, MA?

Casements usually cost more than double-hungs of the same size because of the crank, hinges, and locks. There’s no one price, because every house is different. The final number depends on the window size, the product line and series, insert or full-frame install, any rot we find once the old window is out, exterior trim and color, and glass upgrades. A small basement window and a large custom unit can be very different jobs. That’s why we come to every home, look at each window, and quote it in writing. We’ve been doing this a long time, and our goal is a solution that fits your house, your expectations, and your budget. We also offer 18 months 0% financing.

Are casement windows more energy efficient than double-hung?

Usually, yes. When you lock a casement, the sash presses against the weatherstripping, which seals tighter than two sliding sashes. Both styles can meet ENERGY STAR Northern-zone standards with Low-E glass and argon.

Can I replace a double-hung window with a casement?

Yes. It usually takes a full-frame install, since the old frame was built for sliding sashes. We remove the old window down to the rough opening, flash it, set the new casement, and re-trim. We’ll check that the new size still works with your exterior trim.

How do you clean the outside of a casement window?

Open it and reach through the gap at the hinge side, or use a feature like Marvin’s wash mode on Ultimate casements, which shifts the sash so you can clean the outside glass from indoors.

Do casement windows work for bedroom egress?

Often, yes. Because a casement opens fully, it can meet the bedroom escape-opening rules in the Massachusetts building code with a smaller window than a double-hung. We check every bedroom window during the estimate.

Are casement cranks hard to maintain?

Not really, but they have more moving parts than a double-hung. Keep the track clean and add a little silicone lubricant to the hinge arms once a year. As a house settles over the years, a casement can need a quick hinge or lock adjustment so it closes tight in the corner again. Marvin, ProVia, and Andersen all back their hardware with warranties.

Are casement windows good for kitchens?

They’re one of the best choices. Over a sink or counter, turning a crank is much easier than lifting a sash.

Do I need a permit to replace casement windows in Waltham?

Yes. Massachusetts treats window replacement as an energy code project. We always recommend pulling one, and most of our jobs are permitted. Top Sash pulls the permit with the Waltham Building Department and handles the inspection.

Can I get a screen on a casement window?

Yes. Screens mount on the inside of the window since the sash opens out. Marvin uses BrightView mesh, which lets in more light and air.

Ready for casement windows?

Free in-home estimate, with Marvin, ProVia, and Andersen samples and a clear price.

Top Sash Windows & Doors · Waltham, MA · Serving Greater Boston and Eastern Massachusetts