Calendar Days v Business Days


I was looking for clarification on when to understand “number of days” to be calendar days versus business days. Once construction begins, when the contractor/CM provides the schedule, I understand all days to be calendar days, unless otherwise specified (per study material as well as work experience). Is this assumption true for all phases of an architect’s work, not just CA, or is an architect-provided design schedule assumed to be in business days?

In Practice Exam #3, the following question rides on this point:

An architect has agreed to a proposed schedule that allows for 15 days for schematic design, 15 days for design development, 30 days for construction documents, 14 days for bidding and negotiation, and 30 days for permitting. The owner will have one week for review after each of the design phases.

How many business days into the project should the architect expect to obtain the permit?

The answer is 105 days. One week or five days for owner review is to be provided after SD, DD, and CD phases. SD+5+DD+5+CD+5+Permitting = 15+5+15+5+30+5+30 = 105 days.

Here, the architect proposed schedule simply refers to number of days, with no calendar/business specifier, but the question asks for the answer in business days. If the number of days provided are business days, the answer is 105 as described. However, if the assumption is that number of days provided are calendar days, the answer would be 80 days. (15+7+15+7+30+7+30)*5/7 = 80) In my work in FL I’ve never worked with a design schedule laid out in days, but weeks or simply deliverable dates, is this common in other markets?


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Hi @sillscai ,

Great question about calendar vs. business phases. See prior threads on it below. C&E Clarification Regarding Days - #4 by coachdarionziegler

The A201 does state that ‘day’ refers to calendar day unless stated otherwise. I default to assuming calendar days based on the A201. See snippet form the A201 below:

Personally, I’ve never seen anyone do a schedule in days rather than weeks before either. I suppose anything is possible! It might be more common in single family residential work perhaps.

In regards to this Black Spectacles practice exam question specifically, @coachchrishopstock can you please take a look into it and provide any additional insight?


Thanks, Darion! Appreciate your reply and link to the C&E post. I’ll keep an eye out for Chris’s response as well, to see if there is additional nuance to the specific Black Spectacles Practice Exam question.

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Hi @sillscai thanks for this question!
I agree that it’s difficult to answer without us explicitly stating that the question is referring to business days, so we’ve adjusted the question as such.
One trick that I use sometimes if it’s not clear is that generally, when durations are in multiples of 5, they’re referring to business days, whereas multiples of 7 often refer to calendar days. It’s still best practice to clearly note business vs. calendar days, but in the absence of that information the above may be helpful.