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How to install your new windows and doors

Follow our step-by-step installation guide and learn how and what to look out for during the installation of your new windows.
Enjoy the installation and your new windows!


How to measure

Before ordering new windows and doors, it is important to find the right measurements. Measuring correctly and accurately is not difficult. Our measuring guide will guide you thorugh the proces at home.


Receiving your new windows

Upon receiving your new window frames, it is important to check them carefully for any shipping damage. Also check the order summary and make sure that all windows have been delivered in the correct dimensions.

If you have any questions about your delivery, don't hesitate to contact us. We are ready with advice and guidance via chat, email and phone. You can find our opening hours and contact details here.


Tools for the installation

Once you have checked your new window frames and everything is as it should be, you can start the installation. Before you start, it's a good idea to gather all the tools you need for the installation.

You will need the following:

  • Screwdriver with bits for frame screws and wood drills
  • Hammer / impact drill with long stone drill bit
  • Frame screws
  • Wedges and spacers
  • Insulation and backstop
  • Putty and putty gun
  • Spirit level
  • Folding rule or tape measure


Removal of the old window frame

Remove the old frame by removing the joint around the frame from the outside and removing the screws holding the frame in place. Once the screws are removed, the frame can be lifted out.

Next, make sure the inside of the wall is cleared of excess sealant and plaster so that you are ready to install the new frame. 


Plaatsen van het nieuwe kozijn

Now it is time to install the new window frame. The procedure for installing plastic and wooden frames is the same. When installing wood/aluminium windows or doors, make sure that the joint is placed behind the aluminium surface of the wooden frame.

Insert the frame into the wall window and secure the frame with wedges so that the distance between frame and wall is equal all around.

If the window is very large and heavy, we recommend removing the sash from the frame and installing just the frame.

First check that the bottom sill is level and then adjust the wedges so that the frame is level on all sides, while leaving an equal distance between the frame and the sill. Check that the window opens and closes properly.

Now the sill can be screwed into the wall. Provide spacer blocks where necessary.


Screw down the frame at the marked spots. For window frames less than 1000 mm high, the centre screw in the side post is not necessary. For frames less than 1000 mm wide, the screw in the top and bottom lintel are not necessary.

For windows with multiple sashes, a spacer block should be placed under the vertical stiles.

For swing windows, place the screws as close as possible to the hinges.

Before screwing in the frame, pre-drill the holes. Do this with a wood drill.

It is important to position the screws so that they screw into the brick and not into the joint. Once you have drilled through the frame, use a hammer drill to drill into the brick.

Start by screwing the frame into the corners of the lintel and then continue with the rest of the frame. Place the screws as close to the spacers as possible.

Insulation and sealing

Once the windows are screwed in and correctly installed, put insulation material into the space between the frame and the masonry. Be careful not to stuff this too tightly, as this will reduce the insulating capacity and risk the frame sagging.

After the insulation material, press a backstop into the space between the frame and masonry so that it is 6-10 mm from the front of the window.

NOTE: For timber/aluminium elements, this is the front of the timber frame. As a rule of thumb, the joint should be half as deep as it is wide. If the joint is 12 mm wide, the back stop should be 6 mm from the front edge of the frame.

The window frame can now be sealed from the outside with a hybrid sealant. In most DIY stores, these sealants are referred to as construction sealants or window sealants.

When installing wood/aluminium window frames, make sure that the joint should always be on the wooden part and not on the aluminium profile. This ensures ventilation and prevents moisture from forming between the wood and aluminium.

If the sash has been removed before installation, it can be hung back into the frame after sealing.

Get started with your own window project!

Not found windows and doors for your project yet? Take a look at our large selection.

We produce windows and doors exactly according to your wishes and needs. Choose from more than 300 different models.