How to verify the correctness of window installation?
![](https://cdn.debesto.com/web/assets/2023/05/06090909/dwoch-monterow-sprawdza-okna.jpg)
Do you use the services of subcontractors? Do you run a trading company with an assembly group? Do you want to check if windows are installed correctly?
See how to verify the reliability of assembly in a few steps:
After reading this article you will know:
- How to check if your window is installed correctly
- How to avoid assembly mistakes
- Where big mistakes can be made
- What to do when you find a bug
Step 1 – Check the installation’s foam
Check whether the entire installation’s foam tightly fills the space between the window frame and the jamb. The role of the mounting foam is to fill and seal, not fix the window.
Remember!
The role of the mounting foam is to fill and seal, not fix the window.
![](https://cdn.debesto.com/web/assets/2019/02/06090913/pianka-montazowa-w-oknie-szczelnosc-wizualizacja-2.jpg)
![](https://cdn.debesto.com/web/assets/2019/02/06090910/pianka-montazowa-w-oknie-szczelnosc-wizualizacja2-1.jpg)
Step 2 – Check the fixing elements
Check whether the wall fixing elements (mounting anchors, dowels, self-drilling screws, mounting brackets) are placed 5.91 in from the corners of the inner part of the frame at a distance of max. 1 ft 7.69 in from each other.
Remember!
The role of the mounting foam is to fill and seal, not fix the window.
![](https://cdn.debesto.com/web/assets/2019/02/06090912/odleglosc-miedzy-kotwami-1.jpg)
Step 3 – Check the verticals and horizontals
Use a level to check the verticals and horizontals of each plane. The deviations from the vertical and horizontal should not be more than 0.04 in – 0.08 in per 3 ft 3.37 in of the installed window.
![](https://cdn.debesto.com/web/assets/2019/02/06090912/poziomowanie-okna-wizualizacja.jpg)
Step 4 – Check that the frame is perfectly straight
Use a spirit level to check that the frame is perfectly straight in each plane. Is there a so-called “banana” at some point? Possible allowable deviations from the straight line cannot be more than 0.04 in – 0.08 in on the linear 3 ft 3.37 in of the profile.
If the gaps are larger it is permissible, in case a greater amount of stronger fasteners are used.
![](https://cdn.debesto.com/web/assets/2019/02/06090912/sprawdzenie-rownosc-ramy-okna-z-poziomica.jpg)
![](https://cdn.debesto.com/web/assets/2019/02/06090912/sprawdzenie-rownosc-ramy-okna-z-poziomica2.jpg)
Step 5 – Check stabilizing wedges
Check if every window has permanently fixed stabilizing wedges (marked with the letter “S”), should be installed diagonally and they shouldn’t protrude beyond the outline of the frame. They play a very important role in maintenance of geometry and cannot be removed. Important – wedges must be located diagonally. They cannot be installed in all four corners of the window.
Important
Wedges must be located diagonally. They cannot be installed in all four corners of the window.
If the gaps are larger it is permissible, in case a greater amount of stronger fasteners are used.
![](https://cdn.debesto.com/web/assets/2019/02/06090912/poprawne-umiejscowienie-klockow-w-oknie.jpg)
Step 6 – Check the place window of load-bearings
The window must be placed on the window sill or load-bearing blocks (spaced max. 1 ft 7.69 in), which do not protrude beyond the frame of the window. These blocks cannot be removed under any circumstances! The window cannot stand on the foam only!
Important
Wedges must be located diagonally. They cannot be installed in all four corners of the window.
![](https://cdn.debesto.com/web/assets/2019/02/06090911/poprawny-montaz-okna.jpg)
Step 7 – Check the geometry of the window
Check the geometry of the window – first, if the edges of the sash are visually parallel to the edge of the frame. Then check that the diagonals of the windows are equal. A properly installed window should work properly without any adjustments.
![](https://cdn.debesto.com/web/assets/2019/02/06090911/poprawny-montaz-okna-przekatne.jpg)
Step 8 – Check all the functions of the window
Check all the functions of the window – nothing should stick or rub and the fitting mechanisms should work flawlessly.
Step 9 – 0.59 in – 0.98 in of dilatation
The expansion gaps between the window frame and the jamb should be in the range of 0.59 in – 0.98 in. If they are larger, it is permissible in case a greater amount of stronger fasteners are used.
![](https://cdn.debesto.com/web/assets/2019/02/06090910/szerokosc-dylkatacji-okna-wizualizacja.jpg)