Consideration of shading factors

Shane Regan — Mon, 24 Aug 2020 09:13:45 GMT

Current Revision posted to Hevacomp Wiki by Shane Regan on 8/24/2020 9:13:45 AM

	Product(s):	Hevacomp Mechanical Designer
	Version(s):	V8i (N/A)
	Environment:	N/A
	Area:	N/A
	Subarea:	N/A

Overview

The PartL 2013 calculation utilises a number of methods for considering shading factors.

Method

In terms of shading for PartL there are three considerations:

Overhangs
External shading devices/fins
Internal blinds

Overhangs and fins

This information can be entered under the "Misc." page in PartL, on the "Additional surface data" tab.

Once a Window is selected, the Glazing data input becomes active. Please note that, as described in our Glazing Data wiki, the Shading position will depend on the Blind type selecting for that glazing type, within the Glazing Data menu:

Transmission Factor

A Transmission Factor can be applied to windows to allow overhangs and fins to be considered. This method is taken from the iSBEM manual. Note that Transmission Factor is analogous with Correction Factor in Part L 2010

75.6 Transmission correction factors
The transmission correction factor for windows can be calculated from:

TS = Fo Ff

where

Fo is the partial shading correction factor for overhangs

Ff is the partial shading correction factor for fins

A transmission factor of 1 refers to 100% of light transmitted; i.e. no shading from fins or overhangs

Shading from overhangs and fins

Shading from overhangs and fins depends on the overhang or fin angle, latitude, orientation and local climate. Seasonal shading correction factors for typical climates are given in Tables 10 and 11. The effect of shading from the horizon - ground, trees, other buildings - is not considered by the SBEM calculation engine.

Figure 43: Shading from overhangs and fins

For the purpose of this calcualtion, the angles alpha and beta (dashed lines) are taken between
the plane of the window and overhand of fin shadow at mid window.

Table 10: Partial shading correction for overhang, FoTable 11: Partial shading correction for overhang, Ff

Projection Ratio

This is the 'developed area to projected area' ratio for the window or rooflight. The developed area is the total area of glass plus the frame, and the projected area is the area of the opening in the wall/roof. For domed or conical rooflights this ratio can be larger than 1. For typical windows and flat rooflights, the ratio would be 1.

This figure cannot be less than 1. The default figure for windows is 1, and for rooflights is 1.3

Frame Factor

Frame Factor is the ratio of the window or rooflight are which is occupied by the frame to the total window or rooflight area. The default value is 0.1 for a window (10% of the total area is frame, 90% is glazing) and 0.3 for a rooflight (30% of the total area is frame, 70% is glazing). This ratio must be between 0 and 1.

Internal Blinds

At this stage the SBEM calculation engine does not support internal blinds

From iSBEM users guide:

"SBEM currently does not model the re-radiation effects of blinds where
solar gain entered the space before it is modulated by the shading device"

Tags: SBEM, Hevacomp Mechanical Designer, PartL, shading factors

Consideration of shading factors

Duncan Brown — Tue, 23 May 2017 14:23:44 GMT

Revision 16 posted to Hevacomp Wiki by Duncan Brown on 5/23/2017 2:23:44 PM

	Product(s):	Hevacomp Mechanical Designer
	Version(s):	V8i (N/A)
	Environment:	N/A
	Area:	N/A
	Subarea:	N/A

Overview

The PartL 2013 calculation utilises a number of methods for considering shading factors.

Method

In terms of shading for PartL there are three considerations:

Overhangs
External shading devices/fins
Internal blinds

Overhangs and fins

This information can be entered under the "Misc." page in PartL, on the "Additional surface data" tab.

Transmission Factor

75.6 Transmission correction factors
The transmission correction factor for windows can be calculated from:

TS = Fo Ff

where

Fo is the partial shading correction factor for overhangs

Ff is the partial shading correction factor for fins

A transmission factor of 1 refers to 100% of light transmitted; i.e. no shading from fins or overhangs

Shading from overhangs and fins

Figure 43: Shading from overhangs and fins

For the purpose of this calcualtion, the angles alpha and beta (dashed lines) are taken between
the plane of the window and overhand of fin shadow at mid window.

Table 10: Partial shading correction for overhang, FoTable 11: Partial shading correction for overhang, Ff

Projection Ratio

This figure cannot be less than 1. The default figure for windows is 1, and for rooflights is 1.3

Frame Factor

Internal Blinds

At this stage the SBEM calculation engine does not support internal blinds

From iSBEM users guide:

"SBEM currently does not model the re-radiation effects of blinds where
solar gain entered the space before it is modulated by the shading device"

Tags: SBEM, Hevacomp Mechanical Designer, PartL, shading factors

Consideration of shading factors

Duncan Brown — Tue, 28 Mar 2017 11:50:58 GMT

Revision 15 posted to Hevacomp Wiki by Duncan Brown on 3/28/2017 11:50:58 AM

	Product(s):	Hevacomp Mechanical Designer
	Version(s):	V8i (N/A)
	Environment:	N/A
	Area:	N/A
	Subarea:	N/A

Overview

The PartL 2013 calculation utilises a number of methods for considering shading factors.

Method

In terms of shading for PartL there are three considerations:

Overhangs
External shading devices/fins
Internal blinds

Overhangs and fins

This information can be entered under the "Misc." page in PartL, on the "Additional surface data" tab.

Transmission factor - This is applied to windows to allow overhangs and fins to be considered.

This method is taken from the iSBEM manual
(Transmission factor is analogous with correction factor in Part L 2010)

75.6 Transmission correction factors
The transmission correction factor for windows can be calculated from:

TS = Fo Ff

where

Fo is the partial shading correction factor for overhangs

Ff is the partial shading correction factor for fins

A transmission factor of 1 refers to 100% of light transmitted; i.e. no shading from fins or overhangs

The effect of shading from the horizon; for e.g. ground, trees, other buildings
is not considered by the SBEM calculation engine.

Shading from overhangs and fins

Shading from overhangs and fins depends on the overhang or fin angle, latitude, orientation and local climate. Seasonal shading correction factors for typical climates are given in Tables 10 and 11

Figure 43: Shading from overhangs and fins

For the purposes of this calculation, the angles alpha and beta
- indicated by the dashed lines in Figure 43 -
are taken between the plane of the window and the overhang or fin shadow at mid window.

Table 10: Partial shading correction for overhang, Fo

Table 11: Partial shading correction for overhang, Ff

Projection Ratio - is the 'developed area to projected area' ratio for the window or rooflight. The developed area is the total area of glass plus the frame, and the projected area is the area of the opening in the wall/roof. For domed or conical rooflights this ratio can be larger than 1. For typical windows and flat rooflights, the ratio would be 1.

This figure cannot be less than 1. The default figure for windows is 1, and for rooflights is 1.3

Frame Factor - is the ratio of the window or rooflight are which is occupied by the frame to the total window or rooflight area. The default value is 0.1 for a window (10% of the total area is frame, 90% is glazing) and 0.3 for a rooflight (30% of the total area is frame, 70% is glazing). This ratio must be between 0 and 1.

Internal Blinds

At this stage the SBEM calculation engine does not support internal blinds

From iSBEM users guide:

"SBEM currently does not model the re-radiation effects of blinds where
solar gain entered the space before it is modulated by the shading device"

Tags: SBEM, Hevacomp Mechanical Designer, PartL, shading factors

Consideration of shading factors

Duncan Brown — Wed, 02 Nov 2016 16:46:39 GMT

Revision 14 posted to Hevacomp Wiki by Duncan Brown on 11/2/2016 4:46:39 PM

	Product(s):	Hevacomp Mechanical Designer
	Version(s):	V8i (N/A)
	Environment:	N/A
	Area:	N/A
	Subarea:	N/A

Overview

The PartL 2013 calculation utilises a number of methods for considering shading factors.

Method

In terms of shading for PartL there are three considerations:

Overhangs
External shading devices/fins
Internal blinds

Overhangs and fins

This information can be entered under the "Misc." page in PartL, on the "Additional surface data" tab.

Transmission factor - This is applied to windows to allow overhangs and fins to be considered.

This method is taken from the iSBEM manual
(Transmission factor is analogous with correction factor in Part L 2010)

75.6 Transmission correction factors
The transmission correction factor for windows can be calculated from:

TS = Fo Ff

where

Fo is the partial shading correction factor for overhangs

Ff is the partial shading correction factor for fins

A transmission factor of 1 refers to 100% of light transmitted; i.e. no shading from fins or overhangs

The effect of shading from the horizon; for e.g. ground, trees, other buildings
is not considered by the SBEM calculation engine.

Shading from overhangs and fins

Shading from overhangs and fins depends on the overhang or fin angle, latitude, orientation and local climate. Seasonal shading correction factors for typical climates are given in Tables 10 and 11

Figure 43: Shading from overhangs and fins

For the purposes of this calculation, the angles alpha and beta
- indicated by the dashed lines in Figure 43 -
are taken between the plane of the window and the overhang or fin shadow at mid window.

Table 10: Partial shading correction for overhang, Fo

Table 11: Partial shading correction for overhang, Ff

This figure cannot be less than 1. The default figure for windows is 1, and for rooflights is 1.3

Internal Blinds

At this stage the SBEM calculation engine does not support internal blinds

From iSBEM users guide:

"SBEM currently does not model the re-radiation effects of blinds where
solar gain entered the space before it is modulated by the shading device"

Tags: SBEM, Hevacomp Mechanical Designer, PartL, shading factors

Consideration of shading factors

Duncan Brown — Wed, 02 Nov 2016 16:44:50 GMT

Revision 13 posted to Hevacomp Wiki by Duncan Brown on 11/2/2016 4:44:50 PM

	Product(s):	Hevacomp Mechanical Designer
	Version(s):	V8i (N/A)
	Environment:	N/A
	Area:	N/A
	Subarea:	N/A

Overview

The PartL 2013 calculation utilises a number of methods for considering shading factors.

Method

In terms of shading for PartL there are three considerations:

Overhangs
External shading devices/fins
Internal blinds

Overhangs and fins

This information can be entered under the "Misc." page in PartL, on the "Additional surface data" tab.

Transmission factor - This is applied to windows to allow overhangs and fins to be considered.

This method is taken from the iSBEM manual - (Transmission factor is analogous with correction factor in Part L 2010)

75.6 Transmission correction factors
The transmission correction factor for windows can be calculated from:

TS = Fo Ff

where

Fo is the partial shading correction factor for overhangs

Ff is the partial shading correction factor for fins

A transmission factor of 1 refers to 100% of light transmitted; i.e. no shading from fins or overhangs

The effect of shading from the horizon; for e.g. ground, trees, other buildings
is not considered by the SBEM calculation engine.

Shading from overhangs and fins

Shading from overhangs and fins depends on the overhang or fin angle, latitude, orientation and local climate. Seasonal shading correction factors for typical climates are given in Tables 10 and 11

Figure 43: Shading from overhangs and fins

For the purposes of this calculation, the angles alpha and beta - indicated by the dashed lines in Figure 43 -
are taken between the plane of the window and the overhang or fin shadow at mid window.

Table 10: Partial shading correction for overhang, Fo

Table 11: Partial shading correction for overhang, Ff

This figure cannot be less than 1. The default figure for windows is 1, and for rooflights is 1.3

Internal Blinds

At this stage the SBEM calculation engine does not support internal blinds

From iSBEM users guide:

"SBEM currently does not model the re-radiation effects of blinds where
solar gain entered the space before it is modulated by the shading device"

Tags: SBEM, Hevacomp Mechanical Designer, PartL, shading factors

Consideration of shading factors

Stephen Brown — Thu, 23 Jul 2015 15:19:15 GMT

Revision 12 posted to Hevacomp Wiki by Stephen Brown on 7/23/2015 3:19:15 PM


	Applies To

	Product(s):	Hevacomp Mechanical Designer
	Version(s):	V8i
	Environment:	N/A
	Area:	N/A
	Subarea:	N/A
	Original Author:	Bentley Technical Support Group

Overview

The PartL 2013 calculation utilises a number of methods for considering shading factors.

Method

In terms of shading for PartL there are three considerations:

Overhangs
External shading devices/fins
Internal blinds

Overhangs and fins

This information can be entered under the "Misc." page in PartL, on the "Additional surface data" tab.

Transmission factor - This is applied to windows to allow overhangs and fins to be considered.

This method is taken from the iSBEM manual - (Transmission factor is analogous with correction factor in Part L 2010)

75.6 Transmission correction factors
The transmission correction factor for windows can be calculated from:

TS = Fo Ff

where

Fo is the partial shading correction factor for overhangs

Ff is the partial shading correction factor for fins

A transmission factor of 1 refers to 100% of light transmitted; i.e. no shading from fins or overhangs

The effect of shading from the horizon; for e.g. ground, trees, other buildings
is not considered by the SBEM calculation engine.

Shading from overhangs and fins

Shading from overhangs and fins depends on the overhang or fin angle, latitude, orientation and local climate. Seasonal shading correction factors for typical climates are given in Tables 10 and 11

Figure 43: Shading from overhangs and fins

For the purposes of this calculation, the angles alpha and beta - indicated by the dashed lines in Figure 43 -
are taken between the plane of the window and the overhang or fin shadow at mid window.

Table 10: Partial shading correction for overhang, Fo

Table 11: Partial shading correction for overhang, Ff

This figure cannot be less than 1. The default figure for windows is 1, and for rooflights is 1.3

Internal Blinds

At this stage the SBEM calculation engine does not support internal blinds

From iSBEM users guide:

"SBEM currently does not model the re-radiation effects of blinds where
solar gain entered the space before it is modulated by the shading device"

For an important note on the PartL calculation, please click here

External Links

Bentley homepage

HevacompMechanical Designer

Bentley Technical Support KnowledgeBase

Bentley LEARN Server

Comments or Corrections?

Bentley's Technical Support Group requests that you please confine any comments you have on this Wiki entry to this "Comments or Corrections?" section. THANK YOU!

Tags: SELECTservices, SBEM, TechNote, PartL, shading factors

Consideration of shading factors

Stephen Brown — Thu, 23 Jul 2015 15:18:44 GMT

Revision 11 posted to Hevacomp Wiki by Stephen Brown on 7/23/2015 3:18:44 PM


	Applies To

	Product(s):	Hevacomp Mechanical Designer
	Version(s):	V8i
	Environment:	N/A
	Area:	N/A
	Subarea:	N/A
	Original Author:	Bentley Technical Support Group

Overview

The PartL 2013 calculation utilises a number of methods for considering shading factors.

Method

In terms of shading for PartL there are three considerations:

Overhangs
External shading devices/fins
Internal blinds

Overhangs and fins

This information can be entered under the "Misc." page in PartL, on the "Additional surface data" tab.

Transmission factor - This is applied to windows to allow overhangs and fins to be considered.

This method is taken from the iSBEM manual - (Transmission factor is analogous with correction factor in Part L 2010)

75.6 Transmission correction factors
The transmission correction factor for windows can be calculated from:

TS = Fo Ff

where

Fo is the partial shading correction factor for overhangs

Ff is the partial shading correction factor for fins

A transmission factor of 1 refers to 100% of light transmitted; i.e. no shading from fins or overhangs

The effect of shading from the horizon; for e.g. ground, trees, other buildings
is not considered by the SBEM calculation engine.

Shading from overhangs and fins

Shading from overhangs and fins depends on the overhang or fin angle, latitude, orientation and local climate. Seasonal shading correction factors for typical climates are given in Tables 10 and 11

Figure 43: Shading from overhangs and fins

For the purposes of this calculation, the angles alpha and beta - indicated by the dashed lines in Figure 43 -
are taken between the plane of the window and the overhang or fin shadow at mid window.

Table 10: Partial shading correction for overhang, Fo

Table 11: Partial shading correction for overhang, Ff

This figure cannot be less than 1. The default figure for windows is 1, and for rooflights is 1.3

Internal Blinds

At this stage the SBEM calculation engine does not support internal blinds

From iSBEM users guide:

"SBEM currently does not model the re-radiation effects of blinds where
solar gain entered the space before it is modulated by the shading device"

For an important note on the PartL calculation, please click here

External Links

Bentley homepage

HevacompMechanical Designer

Bentley Technical Support KnowledgeBase

Bentley LEARN Server

Comments or Corrections?

Bentley's Technical Support Group requests that you please confine any comments you have on this Wiki entry to this "Comments or Corrections?" section. THANK YOU!

Tags: SELECTservices, SBEM, TechNote, PartL, shading factors

Consideration of shading factors

Shane Regan — Tue, 10 Mar 2015 15:36:25 GMT

Revision 10 posted to Hevacomp Wiki by Shane Regan on 3/10/2015 3:36:25 PM


	Applies To

	Product(s):	Hevacomp Mechanical Designer
	Version(s):	V8i
	Environment:	N/A
	Area:	N/A
	Subarea:	N/A
	Original Author:	Bentley Technical Support Group

Overview

The PartL 2013 calculation utilises a number of methods for considering shading factors.

Method

In terms of shading for PartL there are three considerations:

Overhangs
External shading devices/fins
Internal blinds

Overhangs and fins

This information can be entered under the "Misc." page in PartL, on the "Additional surface data" tab.

Transmission factor - This is applied to windows to allow overhangs and fins to be considered.

This method is taken from the iSBEM manual - (Transmission factor is analogous with correction factor in Part L 2010)

75.6 Transmission correction factors
The transmission correction factor for windows can be calculated from:

TS = Fo Ff

where

Fo is the partial shading correction factor for overhangs

Ff is the partial shading correction factor for fins

A transmission factor of 1 refers to 100% of light transmitted; i.e. no shading from fins or overhangs

The effect of shading from the horizon; for e.g. ground, trees, other buildings
is not considered by the SBEM calculation engine.

Shading from overhangs and fins

Shading from overhangs and fins depends on the overhang or fin angle, latitude, orientation and local climate. Seasonal shading correction factors for typical climates are given in Tables 10 and 11

Figure 43: Shading from overhangs and fins

For the purposes of this calculation, the angles alpha and beta - indicated by the dashed lines in Figure 43 -
are taken between the plane of the window and the overhang or fin shadow at mid window.

Table 10: Partial shading correction for overhang, Fo

Table 11: Partial shading correction for overhang, Ff

This figure cannot be less than 1. The default figure for windows is 1, and for rooflights is 1.3

Internal Blinds - At this stage the SBEM calculation engine does not support internal blinds

From iSBEM users guide:

"SBEM currently does not model the re-radiation effects of blinds where
solar gain entered the space before it is modulated by the shading device"

For an important note on the PartL calculation, please click here

External Links

Bentley homepage

HevacompMechanical Designer

Bentley Technical Support KnowledgeBase

Bentley LEARN Server

Comments or Corrections?

Bentley's Technical Support Group requests that you please confine any comments you have on this Wiki entry to this "Comments or Corrections?" section. THANK YOU!

Tags: SELECTservices, SBEM, TechNote, PartL, shading factors

Consideration of shading factors

Shane Regan — Fri, 13 Feb 2015 13:39:30 GMT

Revision 9 posted to Hevacomp Wiki by Shane Regan on 2/13/2015 1:39:30 PM


	Applies To

	Product(s):	Hevacomp Software
	Version(s):	v26
	Environment:	N/A
	Area:	N/A
	Subarea:	N/A
	Original Author:	Bentley Technical Support Group

Overview

The PartL 2013 calculation utilises a number of methods for considering shading factors.

Method

In terms of shading for PartL there are three considerations:

Overhangs
External shading devices/fins
Internal blinds

Overhangs and fins

This information can be entered under the "Misc." page in PartL, on the "Additional surface data" tab.

Transmission factor - This is applied to windows to allow overhangs and fins to be considered.

This method is taken from the iSBEM manual - (Transmission factor is analogous with correction factor in Part L 2010)

75.6 Transmission correction factors
The transmission correction factor for windows can be calculated from:

TS = Fo Ff

where

Fo is the partial shading correction factor for overhangs

Ff is the partial shading correction factor for fins

A transmission factor of 1 refers to 100% of light transmitted; i.e. no shading from fins or overhangs

The effect of shading from the horizon; for e.g. ground, trees, other buildings
is not considered by the SBEM calculation engine.

Shading from overhangs and fins

Shading from overhangs and fins depends on the overhang or fin angle, latitude, orientation and local climate. Seasonal shading correction factors for typical climates are given in Tables 10 and 11

Figure 43: Shading from overhangs and fins

For the purposes of this calculation, the angles alpha and beta - indicated by the dashed lines in Figure 43 -
are taken between the plane of the window and the overhang or fin shadow at mid window.

Table 10: Partial shading correction for overhang, Fo

Table 11: Partial shading correction for overhang, Ff

This figure cannot be less than 1. The default figure for windows is 1, and for rooflights is 1.3

Internal Blinds - At this stage the SBEM calculation engine does not support internal blinds

From iSBEM users guide:

"SBEM currently does not model the re-radiation effects of blinds where
solar gain entered the space before it is modulated by the shading device"

For an important note on the PartL calculation, please click here

External Links

Bentley homepage

HevacompMechanical Designer

Bentley Technical Support KnowledgeBase

Bentley LEARN Server

Comments or Corrections?

Bentley's Technical Support Group requests that you please confine any comments you have on this Wiki entry to this "Comments or Corrections?" section. THANK YOU!

Tags: SELECTservices, SBEM, TechNote, PartL, shading factors

Consideration of shading factors

Shane Regan — Fri, 13 Feb 2015 09:28:07 GMT

Revision 8 posted to Hevacomp Wiki by Shane Regan on 2/13/2015 9:28:07 AM


	Applies To

	Product(s):	Hevacomp Software
	Version(s):	v26
	Environment:	N/A
	Area:	N/A
	Subarea:	N/A
	Original Author:	Bentley Technical Support Group

Overview

The PartL 2013 calculation utilises a number of methods for considering shading factors.

Method

In terms of shading for PartL there are three considerations:

Overhangs
External shading devices/fins
Internal blinds

Overhangs and fins

This information can be entered under the "Misc." page in PartL, on the "Additional surface data" tab.

Once a Window is selected, the Glazing data input becomes active. Please note that the Shading position will depend on the Blind type selecting for that glazing type, within the Glazing Data menu:

Transmission factor - This is applied to windows to allow overhangs and fins to be considered.

This method is taken from the iSBEM manual - (Transmission factor is analogous with correction factor in Part L 2010)

75.6 Transmission correction factors
The transmission correction factor for windows can be calculated from:

TS = Fo Ff

where

Fo is the partial shading correction factor for overhangs

Ff is the partial shading correction factor for fins

A transmission factor of 1 refers to 100% of light transmitted; i.e. no shading from fins or overhangs

The effect of shading from the horizon; for e.g. ground, trees, other buildings
is not considered by the SBEM calculation engine.

Shading from overhangs and fins

Shading from overhangs and fins depends on the overhang or fin angle, latitude, orientation and local climate. Seasonal shading correction factors for typical climates are given in Tables 10 and 11

Figure 43: Shading from overhangs and fins

For the purposes of this calculation, the angles alpha and beta - indicated by the dashed lines in Figure 43 -
are taken between the plane of the window and the overhang or fin shadow at mid window.

Table 10: Partial shading correction for overhang, Fo

Table 11: Partial shading correction for overhang, Ff

This figure cannot be less than 1. The default figure for windows is 1, and for rooflights is 1.3

Internal Blinds - At this stage the SBEM calculation engine does not support internal blinds

From iSBEM users guide:

"SBEM currently does not model the re-radiation effects of blinds where
solar gain entered the space before it is modulated by the shading device"

For an important note on the PartL calculation, please click here

External Links

Bentley homepage

HevacompMechanical Designer

Bentley Technical Support KnowledgeBase

Bentley LEARN Server

Comments or Corrections?

Bentley's Technical Support Group requests that you please confine any comments you have on this Wiki entry to this "Comments or Corrections?" section. THANK YOU!

Tags: SELECTservices, SBEM, TechNote, PartL, shading factors

Consideration of shading factors

Duncan Brown — Tue, 09 Dec 2014 12:04:20 GMT

Revision 7 posted to Hevacomp Wiki by Duncan Brown on 12/9/2014 12:04:20 PM


	Applies To

	Product(s):	Hevacomp Software
	Version(s):	V8i
	Environment:	N/A
	Area:	N/A
	Subarea:	N/A
	Original Author:	Bentley Technical Support Group

Overview

The PartL 2010 calculation utilises a number of methods for considering shading factors.

This document refers to PartL 2010 only.

The 2013 regulations provide more concise methods for considering shading.

Method

In terms of shading for PartL there are three considerations:

Overhangs
External shading devices/fins
Internal blinds

Overhangs and fins

This information can be entered under the "Misc." page in PartL, on the "Additional surface data" tab.

Once a Window is selected, the Glazing data input becomes active.

Shading correction factor - This is applied to windows to allow overhangs and fins to be considered.

This method is taken from the iSBEM manual - Transmission factor is analogous with correction factor

75.6 Transmission correction factors
The transmission correction factor for windows can be calculated from:

TS = Fo Ff

where

Fo is the partial shading correction factor for overhangs

Ff is the partial shading correction factor for fins

A transmission factor of 1 refers to 100% of light transmitted; i.e. no shading from fins or overhangs

The effect of shading from the horizon; for e.g. ground, trees, other buildings
is not considered by the SBEM calculation engine.

Shading from overhangs and fins

Shading from overhangs and fins depends on the overhang or fin angle, latitude, orientation and local climate. Seasonal shading correction factors for typical climates are given in Tables 10 and 11

Figure 43: Shading from overhangs and fins

For the purposes of this calculation, the angles alpha and beta - indicated by the dashed lines in Figure 43 -
are taken between the plane of the window and the overhang or fin shadow at mid window.

Table 10: Partial shading correction for overhang, Fo

Table 11: Partial shading correction for overhang, Ff

This figure cannot be less than 1. The default figure for windows is 1, and for rooflights is 1.3

Internal Blinds - At this stage the SBEM calculation engine does not support internal blinds

From iSBEM users guide:

"SBEM currently does not model the re-radiation effects of blinds where
solar gain entered the space before it is modulated by the shading device"

For an important note on the PartL calculation, please click here

External Links

Bentley homepage

HevacompMechanical Designer

Bentley Technical Support KnowledgeBase

Bentley LEARN Server

Comments or Corrections?

Bentley's Technical Support Group requests that you please confine any comments you have on this Wiki entry to this "Comments or Corrections?" section. THANK YOU!

Tags: SELECTservices, SBEM, TechNote, PartL, shading factors

Consideration of shading factors

Duncan Brown — Thu, 28 Aug 2014 10:41:12 GMT

Revision 6 posted to Hevacomp Wiki by Duncan Brown on 8/28/2014 10:41:12 AM


	Applies To

	Product(s):	Hevacomp Software
	Version(s):	V8i
	Environment:	N/A
	Area:	N/A
	Subarea:	N/A
	Original Author:	Bentley Technical Support Group

Overview

The PartL 2010 calculation utilises a number of methods for considering shading factors.

This document refers to PartL 2010 only.
The 2013 regulations provide more concise methods for considering shading.

Method

In terms of shading for PartL there are three considerations:

Overhangs
External shading devices/fins
Internal blinds

Overhangs and fins

This information can be entered under the "Misc." page in Part, on the "Additional surface data" tab.

Once a Window is selected, the Glazing data input becomes active.

Shading correction factor - This is applied to windows to allow overhangs and fins to be considered.

This method is taken from the iSBEM manual - Transmission factor is analogous with correction factor

75.6 Transmission correction factors
The transmission correction factor for windows can be calculated from:

TS = Fo Ff

where

Fo is the partial shading correction factor for overhangs

Ff is the partial shading correction factor for fins

A transmission factor of 1 refers to 100% of light transmitted; i.e. no shading from fins or overhangs

The effect of shading from the horizon; for e.g. ground, trees, other buildings
is not considered by the SBEM calculation engine.

Shading from overhangs and fins

Shading from overhangs and fins depends on the overhang or fin angle, latitude, orientation and local climate. Seasonal shading correction factors for typical climates are given in Tables 10 and 11

Figure 43: Shading from overhangs and fins

For the purposes of this calculation, the angles alpha and beta - indicated by the dashed lines in Figure 43 -
are taken between the plane of the window and the overhang or fin shadow at mid window.

Table 10: Partial shading correction for overhang, Fo

Table 11: Partial shading correction for overhang, Ff

This figure cannot be less than 1. The default figure for windows is 1, and for rooflights is 1.3

Internal Blinds - At this stage the SBEM calculation engine does not support internal blinds

From iSBEM users guide:

"SBEM currently does not model the re-radiation effects of blinds where
solar gain entered the space before it is modulated by the shading device"

For an important note on the PartL calculation, please click here

External Links

Bentley homepage

HevacompMechanical Designer

Bentley Technical Support KnowledgeBase

Bentley LEARN Server

Comments or Corrections?

Bentley's Technical Support Group requests that you please confine any comments you have on this Wiki entry to this "Comments or Corrections?" section. THANK YOU!

Tags: SELECTservices, SBEM, TechNote, PartL, shading factors

Consideration of shading factors

Duncan Brown — Mon, 21 Jul 2014 14:30:35 GMT

Revision 5 posted to Hevacomp Wiki by Duncan Brown on 7/21/2014 2:30:35 PM


	Applies To

	Product(s):	Hevacomp Software
	Version(s):	V8i
	Environment:	N/A
	Area:	N/A
	Subarea:	N/A
	Original Author:	Bentley Technical Support Group

Overview

The PartL 2010 calculation utilises a number of methods for considering shading factors.

Method

In terms of shading for PartL there are three considerations:

Overhangs
External shading devices/fins
Internal blinds

Overhangs and fins

This information can be entered under the "Misc." page in Part, on the "Additional surface data" tab.

Once a Window is selected, the Glazing data input becomes active.

Shading correction factor - This is applied to windows to allow overhangs and fins to be considered.

This method is taken from the iSBEM manual - Transmission factor is analogous with correction factor

75.6 Transmission correction factors
The transmission correction factor for windows can be calculated from:

TS = Fo Ff

where

Fo is the partial shading correction factor for overhangs

Ff is the partial shading correction factor for fins

A transmission factor of 1 refers to 100% of light transmitted; i.e. no shading from fins or overhangs

The effect of shading from the horizon; for e.g. ground, trees, other buildings
is not considered by the SBEM calculation engine.

Shading from overhangs and fins

Shading from overhangs and fins depends on the overhang or fin angle, latitude, orientation and local climate. Seasonal shading correction factors for typical climates are given in Tables 10 and 11

Figure 43: Shading from overhangs and fins

For the purposes of this calculation, the angles alpha and beta - indicated by the dashed lines in Figure 43 -
are taken between the plane of the window and the overhang or fin shadow at mid window.

Table 10: Partial shading correction for overhang, Fo

Table 11: Partial shading correction for overhang, Ff

This figure cannot be less than 1. The default figure for windows is 1, and for rooflights is 1.3

Internal Blinds - At this stage the SBEM calculation engine does not support internal blinds

From iSBEM users guide:

"SBEM currently does not model the re-radiation effects of blinds where
solar gain entered the space before it is modulated by the shading device"

For an important note on the PartL calculation, please click here

External Links

Bentley homepage

HevacompMechanical Designer

Bentley Technical Support KnowledgeBase

Bentley LEARN Server

Comments or Corrections?

Bentley's Technical Support Group requests that you please confine any comments you have on this Wiki entry to this "Comments or Corrections?" section. THANK YOU!

Tags: SELECTservices, SBEM, TechNote, PartL, shading factors

Consideration of shading factors

Elisabeth Pry — Wed, 26 Jun 2013 19:36:13 GMT

Revision 4 posted to Hevacomp Wiki by Elisabeth Pry on 6/26/2013 7:36:13 PM


	Applies To

	Product(s):	Hevacomp Software
	Version(s):	V8i
	Environment:	N/A
	Area:	N/A
	Subarea:	N/A
	Original Author:	Bentley Technical Support Group

Overview

The PartL 2010 calculation utilises a number of methods for considering shading factors.

Method

To view these considerations, please click here

External Links

Bentley homepage

HevacompMechanical Designer

Bentley Technical Support KnowledgeBase

Bentley LEARN Server

Comments or Corrections?

Bentley's Technical Support Group requests that you please confine any comments you have on this Wiki entry to this "Comments or Corrections?" section. THANK YOU!

Tags: SELECTservices, SBEM, TechNote, PartL, shading factors

Consideration of shading factors

Duncan Brown — Tue, 17 Jul 2012 09:13:44 GMT

Revision 3 posted to Hevacomp Wiki by Duncan Brown on 7/17/2012 9:13:44 AM

Document Information

Document Type: Technote

Product(s): Hevacomp Software

Version(s): V8i

Original Author: Bentley Technical Support Group

Overview

The PartL 2010 calculation utilises a number of methods for considering shading factors.

Method

To view these considerations, please click here

External Links

Bentley homepage

HevacompMechanical Designer

Bentley Technical Support KnowledgeBase

Bentley LEARN Server

Comments or Corrections?

Bentley's Technical Support Group requests that you please confine any comments you have on this Wiki entry to this "Comments or Corrections?" section. THANK YOU!

Tags: Technote PartL SBEM shading factors

Part L - Consideration of shading factors [TN]

Duncan Brown — Mon, 16 Jul 2012 13:26:50 GMT

Revision 2 posted to Hevacomp Wiki by Duncan Brown on 7/16/2012 1:26:50 PM

Document Information

Document Type: Technote

Product(s): Hevacomp Software

Version(s): V8i

Original Author: Bentley Technical Support Group

Overview

The PartL 2010 calculation utilises a number of methods for considering shading factors.

Method

To view these considerations, please click here

External Links

Bentley homepage

HevacompMechanical Designer

Bentley Technical Support KnowledgeBase

Bentley LEARN Server

Comments or Corrections?

Bentley's Technical Support Group requests that you please confine any comments you have on this Wiki entry to this "Comments or Corrections?" section. THANK YOU!

Tags: Technote PartL SBEM shading factors

PartL - Consideration of shading factors [TN]

Duncan Brown — Fri, 03 Jun 2011 16:00:18 GMT

Revision 1 posted to Hevacomp Wiki by Duncan Brown on 6/3/2011 4:00:18 PM

Document Information

Document Type: Technote

Product(s): Hevacomp Software

Version(s): V8i

Original Author: Bentley Technical Support Group

Overview

The PartL 2010 calculation utilises a number of methods for considering shading factors.

Method

To view these considerations, please click here

External Links

Bentley homepage

HevacompMechanical Designer

Bentley Technical Support KnowledgeBase

Bentley LEARN Server

Comments or Corrections?

Bentley's Technical Support Group requests that you please confine any comments you have on this Wiki entry to this "Comments or Corrections?" section. THANK YOU!

Tags: Technote PartL SBEM shading factors

Consideration of shading factors

Consideration of shading factors

Overview

Method

Overhangs and fins

Internal Blinds

Consideration of shading factors

Overview

Method

Overhangs and fins

Internal Blinds

Consideration of shading factors

Overview

Method

Overhangs and fins

Internal Blinds

Consideration of shading factors

Overview

Method

Overhangs and fins

Internal Blinds

Consideration of shading factors

Overview

Method

Overhangs and fins

Internal Blinds

Consideration of shading factors

Overview

Method

Overhangs and fins

Internal Blinds

See Also

External Links

Comments or Corrections?

Consideration of shading factors

Overview

Method

Overhangs and fins

Internal Blinds

See Also

External Links

Comments or Corrections?

Consideration of shading factors

Overview

Method

Overhangs and fins

See Also

External Links

Comments or Corrections?

Consideration of shading factors

Overview

Method

Overhangs and fins

See Also

External Links

Comments or Corrections?

Consideration of shading factors

Overview

Method

Overhangs and fins

See Also

External Links

Comments or Corrections?

Consideration of shading factors

Overview

Method

Overhangs and fins

See Also

External Links

Comments or Corrections?

Consideration of shading factors

Overview

Method

Overhangs and fins

See Also

External Links

Comments or Corrections?

Consideration of shading factors

Overview

Method