topic Re: Hydronic Underfloor Heating BIM in Modeling

Hydronic Underfloor Heating BIM

Anonymous — Sun, 10 Dec 2017 02:17:06 GMT

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?

Re: Hydronic Underfloor Heating BIM

Podolsky — Tue, 25 May 2021 22:09:19 GMT

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).

Re: Hydronic Underfloor Heating BIM

gpowless — Wed, 26 May 2021 11:38:42 GMT

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.

Re: Hydronic Underfloor Heating BIM

Laszlo Nagy — Mon, 31 May 2021 06:51:58 GMT

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?

Re: Hydronic Underfloor Heating BIM

Podolsky — Mon, 31 May 2021 10:22:32 GMT

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.

Re: Hydronic Underfloor Heating BIM

Erwin Edel — Mon, 31 May 2021 13:26:45 GMT

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.

Re: Hydronic Underfloor Heating BIM

Podolsky — Mon, 31 May 2021 16:30:42 GMT

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.

Re: Hydronic Underfloor Heating BIM

Anonymous — Mon, 31 May 2021 17:30:58 GMT

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.

Re: Hydronic Underfloor Heating BIM

Podolsky — Mon, 31 May 2021 18:54:13 GMT

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.

Re: Hydronic Underfloor Heating BIM

Erwin Edel — Tue, 01 Jun 2021 10:09:02 GMT

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!

Re: Hydronic Underfloor Heating BIM

Podolsky — Tue, 01 Jun 2021 10:42:11 GMT

Yes, and it's a big problem. I've seen so many bad designed MEP projects (most of them, I guess). And you cannot find it put until you start to stack together pipes on site. Also material waste. MEP engineers don't really care - will they use 20 pipes more, or 20 pipes less. They just draw lines on plan - and all looks OK.
Like I've seen example of underground drainage design made by MEP professionals (it was very small, squeezed design residential) - manholes to drainage was located in the bedrooms under the bed. Why!!!
So I needed to sit, review Osma catalogue, write my own drainage pipes library elements, and re-modelling the whole basement drainage layout 9 times (!) to find the best and optimal layout. Then we ordered EXACTLY parts we needed and builders installed these pipes very fast (always looking into iPads with BIMx), saying that it is as simple as Lego.

Re: Hydronic Underfloor Heating BIM

Erwin Edel — Tue, 01 Jun 2021 12:24:00 GMT

I'm impressed they're willing to use BIMx for this, to be honest. The Dutch market is a system of a lot of sub-contractors for every discipline and it really is a mixed bag from project to project in terms of willingness to use more modern tools.

We really do always ask ourselves if the provided information is likely to be used or just ignored and their own design submitted for approval instead. We do lack some knowledge when it comes to MEP though, so we have some external advisors for this for our more luxury home projects. They generally work with Revit I believe, but still we can clash with their IFC exports.

Re: Hydronic Underfloor Heating BIM

Anonymous — Wed, 02 Jun 2021 10:46:31 GMT

Podolsky wrote:
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.

Yes this is the workflow that GS should adopt. A LOD Model View Option should be created to manage this. This issue reminds me of an old GDL wish, which was the creation of a new Library Global that tells if the object/door/window was cut by a section or 3d Cutaway. To work with Complex Profile LOD... another well known wish. Of course the LOD Model View Option would need to include specific LOD definitions for Plan, Section, 3d and 3d Cutaway. With this, we could bring extremely detailed sections only in the needed elements, avoiding memory overload.