Learning Center

Learning Center » Windows

How to Install & Replace Your Casement Window

How to Install Casement Windows

These stunning windows look great on almost any type of home. They are easily recognizable by the cranks used to open and close them. 

Even though they look better than many other windows, their replacement is similar to that of all other windows. Let’s take a look at what you need and how to do the replacement.

The things you need

First of all, you need the necessary skills. Depending on the type of casement windows you will be using, different levels of abilities may be required.

  • For full-frame replacement windows, you will need a more advanced skillset because the process is moderately complex. We advise you to hire a professional if you have no experience with window replacement.
  • For insert replacement windows, you don’t need advanced skills, as these are relatively simple to install.

Besides the right skills, you need to have the right tools. The right tools depend on each specific project, but in general, you will need:

  • Safety glasses
  • Waterproof shims
  • Caulk gun
  • Gasket sealing tape
  • A level
  • Hammer
  • Screwdriver
  • Power drill or a power driver
  • Putty knife and a utility knife
  • A small pry bar

Casement windows can be made out of metal or vinyl, and there is also a dual-pane model for energy efficiency. Casement window installation is similar to other windows. 

The difference between a casement window vs. other windows is that the hinges are always attached to the side of the frame. These windows can usually be found in older buildings, but they can still be a nice addition to any building. They are produced in various materials and can be opened by hand by the use of a crank. Here is a step-by-step instruction to install a casement window. 

We will assume that there is already a hole in the wall where you plan to install the window and that it has been adequately measured. You also need to buy the correct window. You will also need to purchase all necessary hardware, such as crank mechanism, screw, hinges, and lock.

Step 1: make opening watertight

It is essential that your opening is watertight. You do not want any rain to get between the wall and the window. From the outside, use an aluminum tape or a water seal gasket to seal the opening. Roll out the material, and start from the bottom sill. Fix it both on top as well as under the sill, and make sure to leave no gaps. Proceed with the sides, and ensure it is tightly sealed. 

Your new shingles will go over the top of this, so make sure to extend out on the side and bottom. Make perfect corners, and cut and fold the excess. Finish at the top.

Step 2: level opening

To make sure that the wall opening is level, use your bubble level on the bottom sill. If it isn’t, raise one side with a small shim.

Step 3: place window in opening

The new window will be fixed with a so-called nailing flange. If it’s not already bent, you will have to turn it to a 90-degree angle. That way, when the window is installed, the nailing flange will be flush with the wall. Now it is time to lift the window open.

With the help of another worker, lift the window into the frame and fit it snugly. Make sure the shim hasn’t moved.

Step 4: nail the window

Starting from at the top, hammer a nail into the center hole, then put a pin in every other hole. Make sure your window is still level. If it is, continue putting nails in the rest of the holes in the nailing flange.

Step 5: additional water seal

Put more gasket or aluminum tape over the top nailing flange that helps to ensure that there won’t be any leakage from the top.

Step 6: interior installation

First, you will need to build the casing. Then, you can install all the window hardware.

Step 7: finish work

Now that your window is installed, all that you have to do is finish work. Inside, you will have to hang molding and paint the casing and the molding as necessary. Outside you will have to install a new sill and window frame. Make sure to caulk all openings as further security against leakage. 

In the end, replace any siding or shingles that were removed. 

Do you need help with a casement window installation? We can help. Schedule a free estimate here.

Get a Free Estimate Today

60% off installation. Special financing available. See details.

Get My Free Estimate

Enter today for a chance to win a $50,000 home exterior makeover!

Enter Now

60% off installation or no interest and no payments for two years.

Labor Only. Roofing and siding priced by the square. Not combinable with other offers/promotions. Offer may be withdrawn without notice. Prior sales excluded. Must purchase by 3/31/24 to qualify for special offer. Lifetime Guarantee is for roofing, siding, windows, and gutters. Bathtub and showers offer a no-leak guarantee. Other restrictions may apply.

Disclosure: Plan 2541. Subject to credit approval. Rates range from 14.43% – 18.84% APR (interest rates range from 17.99% – 24.99%). Loan amount and rate will vary based on your income and creditworthiness. 24-month promotional period (“Promo Period”) during which interest is billed but will be waived if the amount financed is paid in full before Promo Period expires. Monthly payments are not required during the Promo Period. Any unpaid balance and amounts owed after Promo Period will be paid over 84 monthly payments. For example, assuming the full credit limit is used on loan approval date and no payments are made during Promo Period, for every $1,000 financed at a fixed interest rate of 24.99%, 24 monthly payments of $0 followed by 84 monthly payments of $31.26. This example is an estimate only. Actual payment amounts based on amount and timing of purchases. Call 866-936-0602 for financing costs and terms. Financing for the GreenSky® consumer loan program is provided by Equal Opportunity Lenders. GreenSky® is a registered trademark of GreenSky, LLC, a subsidiary of Goldman Sachs Bank USA. NMLS #1416362. Loans originated by Goldman Sachs are issued by Goldman Sachs Bank USA, Salt Lake City Branch.

Sachs are issued by Goldman Sachs Bank USA, Salt Lake City Branch. NMLS #208156. www.nmlsconsumeraccess.org