What are passive windows?

Passive windows are those windows that fulfill their function and at the same time limit energy losses . Thanks to its high performance, especially with low transmittance. Thus maintaining comfort inside passive homes .

Precisely because of these high features, a passive can have large windows without sacrificing design. But at the same time fulfilling the functions of any window.

  • Above all, naturally illuminate a space in the house. Because there is nothing like natural light to enrich a room or room.
  • Allow views of the house to the outside. Emphasize the interior-exterior relationship of the house. Either towards an interior patio, the sea in his case or garden or mountain areas. A home must be integrated with its surroundings and windows are essential for this.
  • Ventilate . Although in a passive house it is the heat recuperator that ventilates mechanically and efficiently continuously. There will always be times when air circulation is required. Or even at night to perform what is known as fre cooling. Which is a method used in passive to cool a space through the outside air.
  • Design. The aesthetic component of the home and the contrast between the blind and the transparent. The closed envelope and the gaps. Thus configuring the aesthetics of the house.

How do passive windows work?

For a home to be considered passive or of almost zero consumption, it must be very well built. And thus achieve a very low energy demand and therefore consumption, to maintain comfort conditions inside.

Well, in the case of passive or high-performance windows, the same thing happens. It must be manufactured with the best raw materials and solutions in order to offer great thermal performance.

In this way a passive window works with maximum insulation. Both in the frame and in the glass. A low transmittance ensures that outside temperature does not enter the building, maintaining optimal conditions inside.

On the other hand , they will guarantee the airtightness in the meeting between the window and the rest of the envelope . And this is above all thanks to its placement, also in a special and exhaustive way. This ensures that no air escapes between the frame and the wall. Goodbye to those annoying drafts. That cannot be allowed in a passive .

But these concepts are not ambiguous, but are measured, quantified. Because it is the only way to ensure compliance. This is how terms such as thermal transmittance or solar factor appear. These values ​​are calculated in PHPP to obtain the behavior of the house. Thus analyzing the energy demand based on how it has been designed.

And to get these values, it will depend on how that window has been configured and manufactured. If the glasses are double or triple. If it carries argon gas inside, which is more insulating. Of course, the material of the frame, being the PVC passive windows or the wooden passive windows the ones that obtain the best transmittance values.

In the cases of PVC profiles, it is important to analyze the number of chambers in the profile. And it is that it will be necessary to make sure that there are at least 5 but 6 cameras. Elements such as the double or triple joint or the interlayer material have less incidence but show the degree of demand in this type of windows.

Certified passive windows

Just as a Passive House must be certified if you want to have a full guarantee of the result, the same thing happens with the components. Any constructive element such as a type of insulation, an aerothermal machine or recuperator must have its seal.

With the windows of course the same thing happens. In order to fully guarantee its characteristics, this window must be tested and tested beforehand. And if you meet the requirements of the German passive Institute, you can get your passive component seal. 

In this way, the quality and performance of these passive windows is guaranteed.

How should they be placed?

In addition to being manufactured with high quality so that they have the desired thermal behavior, it is essential to control their placement, as is the case with passive doors . A very good window, poorly placed, is useless. Or almost nothing.

That’s how important its correct placement is. Because it is precisely the point between two materials or two components that is the weakest in an envelope. And that is why you have to make sure that it is installed perfectly on the wall.

For this, it is very important to have a workforce specialized in this type of work. The passive Tradesperson certificate guarantees that this type of work is carried out by trained professionals. And aware of the importance that this has.

Regarding the placement of passive windows, it is essential to do it by means of pre-frames and between these and the window, ensure its correct sealing using special foams and tapes. This will ensure airtightness.

Key aspects of windows in passive houses

In short, these are the key aspects of passive windows in Passive houses

would profile the frame

The passive pvc windows are the ones that give the best performance along with the wooden ones. But the latter have a higher economic cost. It is essential that the profiles have 5 or 6 cameras. Preferably 3 gaskets for tightness against air permeability.


For window glass to be very efficient it must have 2 or preferably 3 chambers. It must also have a noble gas inside such as argon gas. A low-e glass coating can also be installed, which will further help with insulation.


Carried out by specialized professionals, it will ensure its correct insertion in the envelope. Without thermal bridges, guaranteeing continuity in insulation and hermeticity. Through pre-frame and sealing tapes, it is essential in a passive house.


The high performance of frame and glass ensure a very low transmittance value to obtain highly insulating windows.

air tightness

In addition to the joints between the frame and the sash, it will be essential to ensure the tightness between the frame and the wall. To ensure that it is not permeable to air.


This issue depends more on the design, but it is essential to orient the windows and if necessary protect the windows for optimal operation.

And for all this we can say that passive windows, despite having a higher price, are the best on the market. With the best characteristics and therefore behavior afterwards. Ensuring full comfort inside the home.

Passive window security

And this is one of the most recurring concerns among our customers. If a home with many windows may be less secure.

As a general rule, a passive window, due to its composition, is much safer than a traditional one. But in any case, these certified passive windows can be retrofitted with safety glass. Or even with more fixings to the pre-frame or between the sash and the frame.

Thus trying to avoid unfortunate, accidental or provoked events. And guaranteeing the tranquility of the owners of the passive house.