Hydronic Underfloor Heating BIM

[Anonymous]

Is there some kind of BIM for hydronic underfloor heating?

I want to lay the closed loop in a zone and preferably also route the PEX from the heating system. Data from this could be how much cable needed and provide a basis for quotation.

Anybody done this?

[Podolsky]

I've been modelling the whole underfloor heating in quite big art studio. Instead of modelling each loop with bends and straight pipes I created one loop pipe MEP object.
But still I was using separate bends and straight parts too. It would be nice if MEP had plastic pipe as 3D polyline, because in reality it is one continues pipe. Currently schedule instead of showing just one pipe length, needs to be split into pieces, summarising all parts (ie straight parts, bends and loops).

[gpowless]

I am an HVAC designer as well as as a custom home designer and I have found it is far easier to create the hydronic layouts using a polygon line first and then using magic wand and the routing tool to to automatically route the pipe. This way you can make adjustments to the layouts easily and calculate maximum lengths first before committing to the layout.

I start the polygon routing from a location close to the distribution manifold and when I have added the pipe I manually make the connection to the manifold. I use the routing tool to connect each manifold to the circulation plant.

Of course the heat loss and pipe sizing has been completed before this step so I know the number of coils of tubing and spacing I need for each room ahead of time.

I hope this helps.

[Laszlo Nagy]

Podolsky, just out of curiosity: what is the polygon count of that whole underfloor heating model in your screenshot?
Are you using circular section profiles for those geometries? Or do you approximate them with an 8 or 12-segment polygon?

[Podolsky]

Polygon count was total overkill. We were balanced on the upper size of file, that possible to open in BIMx, as we wanted to make real digital twin.
The pipe uses macro, where script, that generates pipe, looks like that:

TUBE 2,NSP/4,EdgeCode+1+2,
0,0,900+1,
ap_pipeRadius, 360, 4000,
USE(NSP)

But the library parts also been controlled via Level of Details - so it was possible to switch between them, to achieve faster computer performance.

This is how this pipe looks like with close look with LOD5, LOD4, LOD3-2 and LOD1. Because code has been written about 4 years ago and was more-less first try - there is a room for improvement in therms on reducing amount of polygons and faster performance.

[Erwin Edel]

Since we mostly have the heating in a subfloor for our projects, what would you say is the benefit of having this as a 3D entity in the project? I can't think of any clashes with the heating since all the electrical (domotica) and plumbing stuff is typically inside the structural slab in our projects and those do need to be checked for sufficient concrete covering of the reinforced steel etc, but in the subfloor there really isn't much to clash with.

Due to legionella we're not allowed to have water pipes anywhere near the heating either, so those are also inside the structural concrete.

Just wondering what we missed and if it would be something to model for us as well.

[Podolsky]

The point on building Digital Twin - is to build everything completely in 3D before building real project. Then real construction process becoming very fast, error free and questions free.
It's a Virtual Construction principle. Well, Virtual Building...

The small example how it works with this project. Supplier is sending 2D DWG with layouts. This layout goes into the project file and literally re-drawn with 3D MEP tool. During this redrawing we are discovering, that some areas can be re-routed, modifying this way the original layout. We also are getting exact length of pipes needs to be ordered. Even amount of plastic clips needed to connect pipes to the insulation layer.
When such a model is created on the client side (developer, contractor) - Digital Twin is the perfect way to check overall architectural and engineering design and make improvements, that usually happens on construction site and cost a lot of money - as delays, unanswered RFI and all this typical madness of construction site.

Shortly - this is the whole concept on which ArchiCAD is based.

[Anonymous]

Erwin wrote:
what would you say is the benefit of having this as a 3D entity in the project?

I am with Podolsky. The digital twin is the natural evolution of BIM. The current state of Virtual Reality and Augmented Reality systems will soon demand this kind of representation. But I think that 3d/Geometry representation must be linked to LOD (Level of Detail). At least until computing processing power become virtually unlimited (See Quantum Computing)... and it looks we will have to wait for a while.

[Podolsky]

The whole point of building complicated 3D models - is to have connection to Level of details. If model everything from static 3D elements (let say modelled from morphs, downloaded from web IFC, RVT or DWG models) - it will kill the system very soon.
This is why I'm connecting all my parts to LOD globals, set in MVO. Objects also sensitive to scale - but only in drawings. Let say the same pipe will be only shown as a polyline on plan 1:50.
Another note is - the model was originally built in Revit, but because of nature of data in Revit - it cannot really produced full Digital Twin higher then LOD3 - that cannot be acceptable for construction. So all building was rebuilt in ArchiCAD. Revit construction documentation was not fully buildable in reality.

The current image of 3D I provided is LOD4. LOD5 also had brackets in the model, but was too heavy.

[Erwin Edel]

In a typical project for us, we'd receive the design of the heating system, check this with our model to see if there are any problems, report these back, receive the final design, approve and then it gets sent out to the building site.

I'm guessing the field of construction work is fairly conservative in most countries, but it certainly is in the Netherlands.

For our large residential villa type projects, very little is ussually truly BIM (as in no classification needed, no IFC exchanged etc). Appartment blocks and similar projects ussually are proper BIM projects, but MEP modelled in 3D at this level I've yet to experience. Hence my curiousity. Thanks for clarifying!