Wishlist radiant constructions

Hi @Chris and @Mostapha,

As you are working hard on the new honeybee+ release with a lot of new features I have one question/wish.
For a lot of buildings we have to simulate radiant floors and/or ceilings. Mostly not all zone’s in the building will have these radiant floors/ceilings. (see image below)
Now we have to split-up the zones define the radiant constructions and and redefine the zones again.
I managed to automate this proces somehow, using the information which is delivered by the solve Adjacencies component, but it makes workflows quite complex and I would like to avoid this splitting up of zone geometry. It would be really nice and practical if these radiant systems could be added zonewise, and honeybee would atomatically assign the right constructions to the right surfaces including the constructions of the adjacent zones.

Even nicer it would be if this could be accomplished:

Hey @Erikbeeren ,

We have not yet put radiant HVAC systems into the new plugin and we will take your suggestion here into account when we do so. Just to make sure that I understand, you are aware that you can customize the radiant constructions however you want using workflows like the one here. But the issue is that your Grasshopper script gets messy with certain types of complex setups and you would like to be able to say “these rooms have radiant floors while these rooms have radiant ceilings and I want to to just build some of these constructions for me.”

Is that correct?

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Yes, that is correct.
I think this could be verry convenient.
It is a pity Energy+ has choosen to make this part of the construction.
Physically perhaps correct, but at the same time really unpractical.
With the solve adjancies step you have al the information needed to generate all constructions with or without internal source in a correct way.

Good to know, @Erikbeeren . It sounds like the biggest headache is getting the construction layers to match in reversed order when you have a radiant floor adjacent to a radiant ceiling. I think we would be able to do some automated checks for this when we implement radiant systems in the new plugins. For legacy, your best bet might be to just use adiabatic boundary conditions for interior surfaces and then you shouldn’t have to worry about matching the two construction layers in reverse order.

I might ask you for some best practices since I imagine that you want a layer of insulation between the radiant floor and radiant ceiling to make sure that, if one of the systems is in heating mode and the other in cooling, the two systems aren’t fighting each other. If you have a suggestion of R-value for this layer, I’ll come back here to reference it when I eventually implement it. Also, if you have a suggestion for how a default radiant ceiling construction should look like, I’ll also take that into account. I know that people tend to use metal panels for radiant ceilings since you aren’t worried about people walking on top of it like you are a radiant floor.

And it definitely doesn’t surprise me that EnergyPlus makes you always put together a detailed specification of the construction. When your primary mode of input is a text editor, your highest priority probably isn’t “ease of use”. But that’s why you have SDK developers and interface developers like the OpenStudio team and Ladybug Tools.

When I have a good working example finished I will send it you. And thank you for the tip with the adiabatic surfaces.


Can I customize radiant constructions with the new HB Opaque Construction? Is the Internal Source available?
With the HB_Legacy I can create the Internal Source Construction but I can’t find the way with the new HB component.

Thank you

@BestiaParda ,

We don’t have support for radiant HVAC in the LBT plugin yet. When I eventually get around to it, I think it will be similar to the legacy plugin where you can specify a special Internal Source material layer within a construction. And I plan to make it available with many of the same heating/cooling sources that are available for the other LBT HVAC templates like ASHP, District Chilled/Hot Water, etc.

FYI, it will be some time before I get to this but I have opened an issue for it:

So you’ll be able to see any progress I make on it there if you are interested in following.


Thank you for your answer. I was trying to run the model with Ironbug and I couln’t specify the Internal Source material.
Happy to hear that you are going to implement the Radiant HVAC Templates.

@BestiaParda ,

Ah, I thought you were asking about Radiant HVAC templates. Not custom Ironbug HVAC. With Ironbug, you should be able to add any custom HVAC you have built to your OpenStudio Models using the workflow @MingboPeng noted here .

Based on a past post (to be fair, it was HB Legacy), I expected to see radiant floor options in the HB DOAS HVAC component, but these comments look as if they have not been added yet?

EDIT: Upon further searching, the post about LB Tools 1.5 release specifically says HB-Energy has multiple presets, so I’m probably just missing them. Part of the issue is I’m having trouble selecting a DOAS radiant heating system that will accept the HB RadiantHVAC Properties component.

The low-temperature radiant system presets are all there under the latest “HB DOAS HVAC Templates” component: