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Daylight Calculations Spreadsheet?

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#1 Fubar



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Posted 10 February 2015 - 07:43 PM

I'm about to do all my daylight calcs, probably write a basic spreadsheet.
On the offchance is there an existing one available anywhere? My spreadsheeting is a bit rusty and it will save me a few hours.


#2 DavidFrancis


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Posted 10 February 2015 - 10:08 PM

Not sure exactly what you want, but have you looked at this site?


See the notes on importing to Excel down the page.

#3 Fubar



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Posted 10 February 2015 - 11:13 PM

different thing, I should have been more specific about the HEA1 calcs for CFSH. I have written a spreadsheet, but there is a problem with the equation used on page 194 of the Code for sustainable housing, it reads DF=(MWuT)/A(1-Rsqd) where u= the angle of visble sky, there must be a sin in the u value as otherewise the equation does not make sense to me. grr.

EDIT: It seems to be as written down in other sources, so the number is fairly irrelevant, other than it must be greater than the specified minimum. heyho, who gives a stuff, so long as it gets through planning. I'm losing the will to live with this CFSH.

Edited by Fubar, 10 February 2015 - 11:27 PM.

#4 Triassic


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Posted 10 February 2015 - 11:33 PM

Is this what you are looking for?

Daylight Factor Calculation Tool Version 1.01
File Format: Microsoft Excel - View as HTML
The spreadsheet tool uses fundamental algorithms and has been bench tested against ... To see grid points with similar daylight factor values, press the “Do ...

Edited by Triassic, 10 February 2015 - 11:34 PM.

#5 Fubar



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Posted 11 February 2015 - 12:07 AM

I found that, but not sure how the celestory measurement works and it seems really complicated compared to the equation specified in the BRE guide. I will give my spreadsheet calcs to the SAP assessor and hopefully it will do the job. saves me £100 anyway for 2 hours work

A useful reference is : http://public.ises.o...Daylight_UK.pdf

Many thanks for the replies.

Edited by Fubar, 11 February 2015 - 12:15 AM.