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How to use Ground Domain object when insulation is above the slab?

asked 2015-06-29 16:59:55 -0500

Xandrika gravatar image

updated 2015-07-11 18:51:59 -0500

It is not very uncommon to insulate the ground floor above the slab. But I can only put the insulation below the slab in the Site:GroundDomain:Slab. Does it not really matter where the insulation is location? Or should I not include the slab in the model and just put the insulation material and the screed layer as slab material?

My actual ground floor construction is as followed:

Construction, NPGRFloor, Brick - burned0.11floor, Cast Concrete (Dense)0.075, Extruded polystyrene 25 mm0.025floor, Floor Screed0.012, Ceramic/clay tiles - ceramic floor tiles Dry0.012;

Material, Brick - burned0.11floor,
Rough,
0.11,
0.85,
1500,
840,
0.9,
0.6,
0.6;

Material, Cast Concrete (Dense)_0.075,
Rough,
0.075,
1.13,
2000,
1000,
0.9,
0.6,
0.6;

Material, Extruded polystyrene 25 mm0.025floor, !- Name Rough,
0.025,
0.027,
40,
1450,
0.9,
0.4,
0.4;

Material, Floor Screed_0.012, Rough,
0.012,
0.41,
1200,
840,
0.9,
0.73,
0.73;

Material, Ceramic/clay tiles - ceramic floor tiles Dry_0.012,
Rough,
0.012,
0.8,
1700,
850,
0.9,
0.6,
0.6;

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answered 2015-06-30 13:28:55 -0500

Define a single layer with the properties of the bottom two layers combined and enter it as a Material. Reference this as the Slab Material Name in the Site:GroundDomain:Slab, where you would also select no insulation. Put the remaining materials, polystyrene and up, in a Construction object for the floor assembly. In your BuildingSurface:Detailed object for the floor of the zone, select the floor assembly object for the Construction Name and select your OCSM object as the Outside Boundary Condition Object. I believe that should do what you want.

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@Adams Rackes. Thanks a lot for your answer. I think, your proposal would be the good solution for in-grade slabs. Any idea how it should look like for on-grade slabs. Thanks a lot.

Xandrika gravatar imageXandrika ( 2015-07-13 08:12:25 -0500 )edit

Even easier. From IORef: "The on-grade slab option can be used to simulate situations when the lower slab surface is near the ground surface level. In this situation, the entire floor must be included within the floor construction object." Just make your whole floor assembly the construction of your zone's floor surface, and apply the OSCM to the outer surface of it. Don't include any insulation in the Site:GroundDomain:Slab, since the insulation will already be in your floor construction.

Adams Rackes gravatar imageAdams Rackes ( 2015-07-15 13:58:30 -0500 )edit

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Asked: 2015-06-29 16:59:55 -0500

Seen: 202 times

Last updated: Jun 29 '15