How to identify surfaces and zones in EnergyPlus IDF data

Identifying surfaces

The first step is to search for the surface reference in the IDF data. For example, if the error is related to surface W_BLOCK1ZONE1_4_0, search for this text. You should then find a definition for the surface, something like:

! Block 1, Zone 1, Wall - 60.843 m2 - 228.4°, Surface Area: 60.843m2

Surface:HeatTransfer, W_BLOCK1ZONE1_4_0, !- Surface name

Wall, 5, !- Class and Construction Name

BLOCK1ZONE1, !- Zone Name

ExteriorEnvironment, !- Outside Face Environment

SunExposed, !- Sun Exposure

WindExposed, !- Wind Exposure

.5, !- View Factor to Ground

4, !- Number vertices

-6.9821656153, 4.4745082117, 0, !- Vertex 1

4.5633022044,-8.5213749335, 0, !- Vertex 2

4.5633022044,-8.5213749335, 3.5, !- Vertex 3

-6.9821656153, 4.4745082117, 3.5; !- Vertex 4

The comment at the top of this surface definition text

! Block 1, Zone 1, Wall - 60.843 m2 - 228.4°, Surface Area: 60.843m2

identifies the block, zone, and surface as described in the DesignBuilder navigator list. 

So the surface is in block Block 1 zone Zone 1 and has an area of 60.843 m2 and an orientation of 228.4°. 

This is usually enough information to identify the surface.

Identifying zones

You can use a similar technique for identifying zones from the zone number. If the zone number is 21 for example search for BLOCK1ZONE1 and you will find a block of text defining the zone such as that below.

! Block 1 - Zone 1

BLOCK1ZONE1, !- Zone Name

0, !- Relative North (to building)

0, !- X Origin (M)

0, !- Y Origin (M)

0, !- Z Origin (M)

At the top of the zone definition text, you will see a comment something like: 

'! Block 1 - Zone 1'

So you know that zone name BLOCK1ZONE1 is actually Zone 1 in Block 1.

For more details about zone naming please read the following program help page https://designbuilder.co.uk/helpv7.0/#Naming.htm