Sefaira - Dutch system


I want to use Sefaira to get an idea what kind of energy changes in a historical building there can be.
In the Netherlands we have a lot of historical buildings that we have to make future proof. We want to make clear what the differences/improvements are in comparison with the current state of the building. We mainly use water-based heating systems (radiators, floor heating, central heating systems, gas based heating systems) in existing buildings but for the improvements we can use other methods.
Can you advice me which HVAC systems can be used in the Sefaira system for the Dutch market?


Hi @sander_hoogland Sefaira currently allows you to apply and edit the following systems below:

Additional information on the systems are available in the Sefaira knowledgebase here as well.


I can see those in the list, but still most of these systems are not for the dutch market.
So when I have an historical house with natural ventilation in and mechanical ventilation out. And heating with a central heating system gas based.
Which system do I need to choose.

Hi Sander,
Have you seen the support documentation on Natural Ventilation?

This should help you.
For your application I would select passive chilled beams (which are like radiators). You can turn the cooling and ventilation off and then you just have heating. If you turn ventilation off I would turn nat vent on and follow the instructions on how to use it.
hope that gets you going!


Hi Corney,

I will give it a try, thanks.

Hello Andrew,

I gave it a shot and I got some data. That I think I can use for a comparison with different isolation values.
In the peak loads for heating, there is a table where you can see what the wall loss is or the floor loss or roof loss. But is there a way to see those all the time and also to make a comparison with the clones I made?


Hi Sander,
You can see the top 3 peak loads reported by zone as shown below.

If you want to see all space loads you can download the E+ sizing report from zone sizing which breaks down all loads by zone.

When you see warmup and cooldown loads in our app it can be confusing. I wrote this article to explain what’s going on.

hope that helps!

Goodmorning Andrew,

When I see a number in the peak loads report where can I find this in the E+ sizing report. So where is the wall loss 17w/2 to be found? Or how can I underpin this number.

Hi @sander_hoogland,

You can find the corresponding peak loads report here:

Zone Sizing Peak Loads

And once you download it, you can find the corresponding peak loads for both Cooling and Heating within each Zone Component Summary:

Zone component load summary

Hope this helps.

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