# Latest

**URL:** https://discourse.ladybug.tools/latest.md?no_subcategories=false&page=1

[Latest](https://discourse.ladybug.tools/latest.md) · [Categories](https://discourse.ladybug.tools/categories.md) · [Tags](https://discourse.ladybug.tools/tags.md)

**Page:** 2

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## [Help resolve compatability matrix for successful urbanopt simulation](https://discourse.ladybug.tools/t/help-resolve-compatability-matrix-for-successful-urbanopt-simulation/40821)

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**Author:** [@olivia01h](https://discourse.ladybug.tools/u/olivia01h)\
**Replies:** 2\
**Last updated:** [October 1, 2026, 12:08am UTC](https://discourse.ladybug.tools/t/help-resolve-compatability-matrix-for-successful-urbanopt-simulation/40821 "2026-10-01T00:08:01Z")

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Hello @chris, I am running into an issue due to the compatibility matrix, the error message I am receiving is Solution exception:The installed URBANopt is version 1.1.0. Must be version 1.4.0 to work with dragonfly. …

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## [Introducing Fairyfly for THERM Simulation with LBT Grasshopper](https://discourse.ladybug.tools/t/introducing-fairyfly-for-therm-simulation-with-lbt-grasshopper/39878)

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**Author:** [@chris](https://discourse.ladybug.tools/u/chris)\
**Replies:** 10\
**Last updated:** [September 30, 2026, 8:25pm UTC](https://discourse.ladybug.tools/t/introducing-fairyfly-for-therm-simulation-with-lbt-grasshopper/39878 "2026-09-30T20:25:46Z")

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Great members of the Ladybug Tools community, After years of you asking us about the future of the Legacy Honeybee THERM capabilities, we are happy to announce that we have finally added a connection to THERM 8 in the l…

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## [Heat Pump Water Heaters on multifamily buildings](https://discourse.ladybug.tools/t/heat-pump-water-heaters-on-multifamily-buildings/40824)

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**Author:** [@Leite](https://discourse.ladybug.tools/u/Leite)\
**Replies:** 0\
**Last updated:** [September 30, 2026, 5:39pm UTC](https://discourse.ladybug.tools/t/heat-pump-water-heaters-on-multifamily-buildings/40824 "2026-09-30T17:39:40Z")

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Hello everyone, Running on a small problem when connecting the DF\_Room2D component to the DF\_SHW component with a HPWH. Modeling a multifamily building with 15 units, and after connecting the room2d output to the “condi…

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## [LadyBug Installer: Python not found](https://discourse.ladybug.tools/t/ladybug-installer-python-not-found/13805)

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**Author:** [@iangreen](https://discourse.ladybug.tools/u/iangreen)\
**Replies:** 6\
**Last updated:** [September 30, 2026, 5:03pm UTC](https://discourse.ladybug.tools/t/ladybug-installer-python-not-found/13805 "2026-09-30T17:03:01Z")

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Hello, I am pretty new to Grasshopper and am trying to install the Ladybug application for grasshopper. I have downloaded 1-2-0 when I drag the installer file to the grasshopper window the two step process shows up and I…

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## [HB Annual Daylight matrices is not working](https://discourse.ladybug.tools/t/hb-annual-daylight-matrices-is-not-working/40816)

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**Author:** [@Snehal](https://discourse.ladybug.tools/u/Snehal)\
**Replies:** 2\
**Last updated:** [September 30, 2026, 11:48am UTC](https://discourse.ladybug.tools/t/hb-annual-daylight-matrices-is-not-working/40816 "2026-09-30T11:48:44Z")

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HB Annual Daylight matrices is not working red Bubble is showing this error \[exception: Failed to compute annual daylight metrics.\]

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## [Issues with Mac Installation](https://discourse.ladybug.tools/t/issues-with-mac-installation/40819)

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**Author:** [@lonofre](https://discourse.ladybug.tools/u/lonofre)\
**Replies:** 0\
**Last updated:** [September 30, 2026, 2:01am UTC](https://discourse.ladybug.tools/t/issues-with-mac-installation/40819 "2026-09-30T02:01:03Z")

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Hello, I am having issues installing Ladybug on Mac. My laptop is a Macbook Air, with a M4 Chip. I’m not sure if it’s because Apple blocks the installation before it can complete, but on the second step it infinitely l…

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## [Dragonfly\_mapper\_measure example failed to run](https://discourse.ladybug.tools/t/dragonfly-mapper-measure-example-failed-to-run/40814)

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**Author:** [@behnammmohseni](https://discourse.ladybug.tools/u/behnammmohseni)\
**Replies:** 3\
**Last updated:** [September 29, 2026, 5:05am UTC](https://discourse.ladybug.tools/t/dragonfly-mapper-measure-example-failed-to-run/40814 "2026-09-29T05:05:26Z")

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Hi everyone, @chris I recently tried to have mapper example simulation using add\_EV\_load in Dragonfly. It seems there is a problem in the OSM measures: and here is the run log errors: \[22:22:38.806924 ERROR\] \[ope…

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## [UTCI Map Energy Simulation Failing After Updating via the LB Versioner](https://discourse.ladybug.tools/t/utci-map-energy-simulation-failing-after-updating-via-the-lb-versioner/40806)

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**Author:** [@Aliarch](https://discourse.ladybug.tools/u/Aliarch)\
**Replies:** 7\
**Last updated:** [September 27, 2026, 11:37am UTC](https://discourse.ladybug.tools/t/utci-map-energy-simulation-failing-after-updating-via-the-lb-versioner/40806 "2026-09-27T11:37:41Z")

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Hi @chris a i hope you are doing well after updating, UTCI raises a error. i tried it on the sample (thermal comfort under a tree) do you know what is this error?

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## [I cannot use LBT with my Rhino educator license](https://discourse.ladybug.tools/t/i-cannot-use-lbt-with-my-rhino-educator-license/40809)

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**Author:** [@PatriciaEdithCampore](https://discourse.ladybug.tools/u/PatriciaEdithCampore)\
**Replies:** 1\
**Last updated:** [September 27, 2026, 12:28am UTC](https://discourse.ladybug.tools/t/i-cannot-use-lbt-with-my-rhino-educator-license/40809 "2026-09-27T00:28:01Z")

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After the last Rhino update, I opened it and LBT tools had disappeared. I reinstallled LBT tools from food4 Rhino. In the command bar appeared this legend: LBT Plugin: C:\\Program Files\\ladybug\_tools\\python\\Lib\\site-pack…

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## [1. Solution exception:The recipe failed to run with the following summary:](https://discourse.ladybug.tools/t/1-solution-exception-the-recipe-failed-to-run-with-the-following-summary/18905)

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**Author:** [@ZHNGLLXXX](https://discourse.ladybug.tools/u/ZHNGLLXXX)\
**Replies:** 18\
**Last updated:** [June 7, 2023, 2:57pm UTC](https://discourse.ladybug.tools/t/1-solution-exception-the-recipe-failed-to-run-with-the-following-summary/18905 "2023-06-07T14:57:23Z")

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Solution exception:The recipe failed to run with the following summary: Scheduled 38 tasks of which: 28 ran successfully: 1 ComputeSphericalViewFactors(…) 1 CopyGridInfo(…) 1 CopyRedistInfo(…) 1 CreateDirectSky(…) 1…

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## [Fixed Interval Schedule crashes on leap year](https://discourse.ladybug.tools/t/fixed-interval-schedule-crashes-on-leap-year/40798)

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**Author:** [@MatteoMerli](https://discourse.ladybug.tools/u/MatteoMerli)\
**Replies:** 5\
**Last updated:** [September 23, 2026, 9:42am UTC](https://discourse.ladybug.tools/t/fixed-interval-schedule-crashes-on-leap-year/40798 "2026-09-23T09:42:11Z")

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Hi @chris I ran into an issue using fixed schedules with leap years. The Fixed Interval Schedule component expects 8760 values (standard year, timestep = 1), but I am running a leap year (2024), and if i supply 8784 va…

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## [Importing LBNL window IDF - SHGC discrepancy](https://discourse.ladybug.tools/t/importing-lbnl-window-idf-shgc-discrepancy/40801)

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**Author:** [@jroberts](https://discourse.ladybug.tools/u/jroberts)\
**Replies:** 2\
**Last updated:** [September 23, 2026, 8:20am UTC](https://discourse.ladybug.tools/t/importing-lbnl-window-idf-shgc-discrepancy/40801 "2026-09-23T08:20:25Z")

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Hi all, I’m importing an IDF file which I’ve exported from LBNL window and saved in C:\\Users\\joe.Roberts\\AppData\\Roaming\\ladybug\_tools\\standards\\constructions. According to LBNL window, the SHGC is 4.9%, but when I chec…

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## [The illuminance calculation of electric light is not correct](https://discourse.ladybug.tools/t/the-illuminance-calculation-of-electric-light-is-not-correct/40799)

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**Author:** [@mrbass](https://discourse.ladybug.tools/u/mrbass)\
**Replies:** 2\
**Last updated:** [September 23, 2026, 7:51am UTC](https://discourse.ladybug.tools/t/the-illuminance-calculation-of-electric-light-is-not-correct/40799 "2026-09-23T07:51:44Z")

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i followed the sample of electric light, but the result seems wrong when I check the illuminance in DIAlux. Did anybody know how to fix this?

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## [HB Visualization--\> Grid Sensor from Room --- \>Recipes: query is If the produced graphs are right or wrong](https://discourse.ladybug.tools/t/hb-visualization-grid-sensor-from-room-recipes-query-is-if-the-produced-graphs-are-right-or-wrong/40797)

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**Author:** [@Snehal](https://discourse.ladybug.tools/u/Snehal)\
**Replies:** 0\
**Last updated:** [September 21, 2026, 9:35am UTC](https://discourse.ladybug.tools/t/hb-visualization-grid-sensor-from-room-recipes-query-is-if-the-produced-graphs-are-right-or-wrong/40797 "2026-09-21T09:35:30Z")

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Hi, I want to upload file to ask my query how should I upload my files.

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## [Ironbug component does not turn red with invalid empty plant branch, fatal EnergyPlus error "Missing required property 'component\_name'"](https://discourse.ladybug.tools/t/ironbug-component-does-not-turn-red-with-invalid-empty-plant-branch-fatal-energyplus-error-missing-required-property-component-name/40795)

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**Author:** [@cpc](https://discourse.ladybug.tools/u/cpc)\
**Replies:** 1\
**Last updated:** [September 20, 2026, 1:20pm UTC](https://discourse.ladybug.tools/t/ironbug-component-does-not-turn-red-with-invalid-empty-plant-branch-fatal-energyplus-error-missing-required-property-component-name/40795 "2026-09-20T13:20:03Z")

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Hello everyone, hope you’re doing well. I’m building HVAC systems with Ironbug + Honeybee 1.8.0 in Grasshopper. Problem 1: Ironbug components do NOT show red/orange warning colour on canvas even when the generated plant…

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## [Bug of DumpVisSet? Or incomplete known issues](https://discourse.ladybug.tools/t/bug-of-dumpvisset-or-incomplete-known-issues/39972)

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**Author:** [@ZhengrongTao](https://discourse.ladybug.tools/u/ZhengrongTao)\
**Replies:** 13\
**Last updated:** [September 18, 2026, 4:57pm UTC](https://discourse.ladybug.tools/t/bug-of-dumpvisset-or-incomplete-known-issues/39972 "2026-09-18T16:57:06Z")

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hi,@chris I am attempting to use the DumpVisSet component to export the SVG image. Its application in the flat or three-dimensional images provided by Ladybug has been very successful. However, when I used the Visualiza…

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## [Ironbug radiant system setup issues](https://discourse.ladybug.tools/t/ironbug-radiant-system-setup-issues/40790)

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**Author:** [@Makaella](https://discourse.ladybug.tools/u/Makaella)\
**Replies:** 1\
**Last updated:** [September 17, 2026, 6:06pm UTC](https://discourse.ladybug.tools/t/ironbug-radiant-system-setup-issues/40790 "2026-09-17T18:06:37Z")

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Hello! I have applied the construction for “INTERNAL SOURCE”, and have checked the construction attribute of the surface and ground. then use the rooms for creating an HB Model. But always receive the error message as fo…

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## [Radiators as radiant surfaces (wall)](https://discourse.ladybug.tools/t/radiators-as-radiant-surfaces-wall/21423)

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**Author:** [@AntonH](https://discourse.ladybug.tools/u/AntonH)\
**Replies:** 9\
**Last updated:** [September 17, 2026, 7:24am UTC](https://discourse.ladybug.tools/t/radiators-as-radiant-surfaces-wall/21423 "2026-09-17T07:24:05Z")

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Hello! I have been trying to set up an energy model for thermal comfort in winter. Is there any way to set a (sub) surface on the wall as a radiator? Or is this type of heating system limited to what is available in the…

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## [Is this a bug in the source code for Calculating DHI?](https://discourse.ladybug.tools/t/is-this-a-bug-in-the-source-code-for-calculating-dhi/40750)

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**Author:** [@cdwu](https://discourse.ladybug.tools/u/cdwu)\
**Replies:** 4\
**Last updated:** [September 16, 2026, 2:19pm UTC](https://discourse.ladybug.tools/t/is-this-a-bug-in-the-source-code-for-calculating-dhi/40750 "2026-09-16T14:19:35Z")

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Hi Mostapha and Chris, While I was working on a research project using the “direct solar irradiance” component in Ladybug, I realized that the equation used to calculate diffuse irradiance for anisotropic sky is (0.313 \*…

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## [Custom EPW file import in Ladybug Grasshopper from PC folder](https://discourse.ladybug.tools/t/custom-epw-file-import-in-ladybug-grasshopper-from-pc-folder/23663)

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**Author:** [@Anastasiia](https://discourse.ladybug.tools/u/Anastasiia)\
**Replies:** 8\
**Last updated:** [September 16, 2026, 10:17am UTC](https://discourse.ladybug.tools/t/custom-epw-file-import-in-ladybug-grasshopper-from-pc-folder/23663 "2026-09-16T10:17:36Z")

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Hello! I am surviving some kind of a crisis here:) The aim of my research is to compare the two summer temperature scenarios (the current situation VS the R.C.P. 4.5 projection to the 2050). I managed to successfully mo…

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## [Simulation Running Failed "ComputeSphericalViewFactors](https://discourse.ladybug.tools/t/simulation-running-failed-computesphericalviewfactors/40782)

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**Author:** [@concreteblock100](https://discourse.ladybug.tools/u/concreteblock100)\
**Replies:** 1\
**Last updated:** [September 16, 2026, 2:14am UTC](https://discourse.ladybug.tools/t/simulation-running-failed-computesphericalviewfactors/40782 "2026-09-16T02:14:17Z")

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Hello friends. Right now, I’m doing a simulation for operative temperature mapping. Previously (yesterday), the simulation can finish perfectly and showed the OT mapping results. However, just today, without changing any…

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## [Design Explorer does not preview](https://discourse.ladybug.tools/t/design-explorer-does-not-preview/23849)

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**Author:** [@SputnikArchitecten](https://discourse.ladybug.tools/u/SputnikArchitecten)\
**Replies:** 5\
**Last updated:** [September 15, 2026, 8:40pm UTC](https://discourse.ladybug.tools/t/design-explorer-does-not-preview/23849 "2026-09-15T20:40:17Z")

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Hi, this is not extacly ladybug issue, however a lot of questions about Design Explorer were actually asked on this forum. Since few days Design Explorer stopped previewing images. We usually use Google Drive links for …

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## [DownloadEPW component not reading file path EPW files](https://discourse.ladybug.tools/t/downloadepw-component-not-reading-file-path-epw-files/40784)

<div class="topic-metadata">

**Author:** [@Rob](https://discourse.ladybug.tools/u/Rob)\
**Replies:** 4\
**Last updated:** [September 15, 2026, 1:00pm UTC](https://discourse.ladybug.tools/t/downloadepw-component-not-reading-file-path-epw-files/40784 "2026-09-15T13:00:25Z")

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The DownloadEPW comes up with an error (below) when trying to use a saved weather file via a file path: Input parameter \_weather\_URL failed to collect data! It seems to keep looking for a web source EPW rather than th…

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## [Honeybee\_radiance cannot import luminaire](https://discourse.ladybug.tools/t/honeybee-radiance-cannot-import-luminaire/40780)

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**Author:** [@joao.pires.i](https://discourse.ladybug.tools/u/joao.pires.i)\
**Replies:** 0\
**Last updated:** [September 14, 2026, 9:46pm UTC](https://discourse.ladybug.tools/t/honeybee-radiance-cannot-import-luminaire/40780 "2026-09-14T21:46:26Z")

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Hello! I am facing a import problem after update the lbt grasshopper to 1.10.54 using the LB Versioner in GH. When I try to use a HB Luminaire it shows: cannot import luminaire from honeybee\_radiance, others components …

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## [Daylight is not transported through a horizontal reflective light pipe in a Point-in-Time Grid study](https://discourse.ladybug.tools/t/daylight-is-not-transported-through-a-horizontal-reflective-light-pipe-in-a-point-in-time-grid-study/40593)

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**Author:** [@fatalay](https://discourse.ladybug.tools/u/fatalay)\
**Replies:** 1\
**Last updated:** [September 13, 2026, 8:42pm UTC](https://discourse.ladybug.tools/t/daylight-is-not-transported-through-a-horizontal-reflective-light-pipe-in-a-point-in-time-grid-study/40593 "2026-09-13T20:42:27Z")

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Hello, I am trying to model a horizontal light pipe entering through the façade using Grasshopper–Honeybee. The internal surface of the pipe is intended to have 99% reflectance, while the exterior collector and interior…

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## [Problem with heating simulation](https://discourse.ladybug.tools/t/problem-with-heating-simulation/40772)

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**Author:** [@anatamargo](https://discourse.ladybug.tools/u/anatamargo)\
**Replies:** 0\
**Last updated:** [September 11, 2026, 10:52am UTC](https://discourse.ladybug.tools/t/problem-with-heating-simulation/40772 "2026-09-11T10:52:01Z")

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Hello, I am carrying out an annual energy simulation of an existing multi-storey building using Rhino 8, Grasshopper and Honeybee. The original project contains confidential company information, so I cannot upload the c…

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## [Simutation problem with gas boiler and baseboard HVAC](https://discourse.ladybug.tools/t/simutation-problem-with-gas-boiler-and-baseboard-hvac/40771)

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**Author:** [@anatamargo](https://discourse.ladybug.tools/u/anatamargo)\
**Replies:** 0\
**Last updated:** [September 11, 2026, 10:50am UTC](https://discourse.ladybug.tools/t/simutation-problem-with-gas-boiler-and-baseboard-hvac/40771 "2026-09-11T10:50:33Z")

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Zero heating consumption with “Baseboard Gas Boiler” HVAC Hello, I am carrying out an annual energy simulation of an existing multi-storey building using Rhino 8, Grasshopper and Honeybee. The original project contains…

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## [Mac Ladybug Installation Hanging](https://discourse.ladybug.tools/t/mac-ladybug-installation-hanging/40759)

<div class="topic-metadata">

**Author:** [@ps3ratt](https://discourse.ladybug.tools/u/ps3ratt)\
**Replies:** 2\
**Last updated:** [September 11, 2026, 6:08am UTC](https://discourse.ladybug.tools/t/mac-ladybug-installation-hanging/40759 "2026-09-11T06:08:41Z")

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I am trying to install LBT 1.10.0 for Rhino 8 on my Macbook M3 Pro however no matter what I try it gets stuck with the spinning wheel on step 2 of the installer .gh file. I have tried installing older versions of LBT, a…

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## [Pollinator install problem loading errors](https://discourse.ladybug.tools/t/pollinator-install-problem-loading-errors/40749)

<div class="topic-metadata">

**Author:** [@Alakelele](https://discourse.ladybug.tools/u/Alakelele)\
**Replies:** 1\
**Last updated:** [September 8, 2026, 3:52pm UTC](https://discourse.ladybug.tools/t/pollinator-install-problem-loading-errors/40749 "2026-09-08T15:52:04Z")

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Hello there, notification at grasshopper start, Rhino 8 windows 11, everything fresh install and last stable version as of 2 days. Priority: CategoryIcon { Call PollinationLogger.LogHelper.OneTimeSetup(ILoggerFactory …

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## [Ladybug/Honeybee on Mac](https://discourse.ladybug.tools/t/ladybug-honeybee-on-mac/40756)

<div class="topic-metadata">

**Author:** [@Murray1111](https://discourse.ladybug.tools/u/Murray1111)\
**Replies:** 3\
**Last updated:** [September 7, 2026, 2:55pm UTC](https://discourse.ladybug.tools/t/ladybug-honeybee-on-mac/40756 "2026-09-07T14:55:24Z")

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Hi all, new here so hope this is the relevant section to ask, I am a Architecture student hoping to start using Ladybug and honeybee plugins with Rhino, my question is how does this run on Mac? Is a MacBook a viable opti…

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