IPMC Table 404.5 Improved

It doesn&a;t make much sense that a house with a 150&h;ft² living room and a 100&h;ft² dining room can accommodate 15 occupants under IPMC table 404.5 when neither of those rooms can accommodate 15 people sitting at tables under IBC table 1004.5. The following table fixes that incongruity.

Occupant count	Minimum area (ft²)
	Per occupant			Total
	Living	Dining	Total	Living	Dining	Total
1	133 + 1/3	0	133 + 1/3	133 + 1/3	0	133 + 1/3
2	66 + 2/3	0	66 + 2/3	133 + 1/3	0	133 + 1/3
3	40	26 + 2/3	66 + 2/3	120	80	200
4	30	20	50	120	80	200
5–∞	25	16 + 2/3	41 + 2/3	—	—	—

Demonstration of how this new table makes more sense than the original table:

Occupant count	Minimum area (ft²)
	Original						Improved
	Total			Per occupant			Per occupant			Total
	Living	Dining	Total	Living	Dining	Total	Living	Dining	Total	Living	Dining	Total
1	120	0	120	120	0	120	133 + 1/3	0	133 + 1/3	133 + 1/3	0	133 + 1/3
2	120	0	120	60	0	60	66 + 2/3	0	66 + 2/3	133 + 1/3	0	133 + 1/3
3	120	80	200	40	26 + 2/3	66 + 2/3	40	26 + 2/3	66 + 2/3	120	80	200
4	120	80	200	30	20	50	30	20	50	120	80	200
5	120	80	200	24	16	40	25	16 + 2/3	41 + 2/3	125	83 + 1/3	208 + 1/3
6	150	100	250	25	16 + 2/3	41 + 2/3	25	16 + 2/3	41 + 2/3	150	100	250
7	150	100	250	21 + 3/7	14 + 2/7	35 + 5/7	25	16 + 2/3	41 + 2/3	175	116 + 2/3	291 + 2/3
8	150	100	250	18 + 3/4	12 + 1/2	31 + 1/4	25	16 + 2/3	41 + 2/3	200	133 + 1/3	333 + 1/3
9	150	100	250	16 + 2/3	11 + 1/9	27 + 7/9	25	16 + 2/3	41 + 2/3	225	150	375
10	150	100	250	15	10	25	25	16 + 2/3	41 + 2/3	250	166 + 2/3	416 + 2/3
11	150	100	250	13 + 7/11	9 + 1/11	22 + 8/11	25	16 + 2/3	41 + 2/3	275	183 + 1/3	458 + 1/3
12	150	100	250	12 + 1/2	8 + 1/3	20 + 5/6	25	16 + 2/3	41 + 2/3	300	200	500
13	150	100	250	11 + 7/13	7 + 9/13	19 + 3/13	25	16 + 2/3	41 + 2/3	325	216 + 2/3	541 + 2/3
14	150	100	250	10 + 5/7	7 + 1/7	17 + 6/7	25	16 + 2/3	41 + 2/3	350	233 + 1/3	583 + 1/3
15	150	100	250	10	6 + 2/3	16 + 2/3	25	16 + 2/3	41 + 2/3	375	250	625
∞	150	100	250	0	0	0	25	16 + 2/3	41 + 2/3	∞	∞	∞

In the improved table, as the occupant count rises, the required areas per occupant (1) fall to reasonable nonzero minimums (taken directly from the original table) rather than nonsensically to zero, and (2) progress steadily downward rather than nonsensically zigzagging up and down (except for weirdness caused by the original table&a;s requiring no dining area at all for occupant counts smaller than three).

If you prefer, you can use different numbers, as long as they are no lower than the numbers in the original table. Here are two examples.

Ensuring that area requirements for occupant count ≥ 7 are integer multiples of 5 ft²:

Occupant count	Minimum area (ft²)
	Per occupant			Total
	Living	Dining	Total	Living	Dining	Total
1	133 + 1/3	0	133 + 1/3	133 + 1/3	0	133 + 1/3
2	66 + 2/3	0	66 + 2/3	133 + 1/3	0	133 + 1/3
3	40	26 + 2/3	66 + 2/3	120	80	200
4	30	20	50	120	80	200
5	25	16 + 2/3	41 + 2/3	125	83 + 1/3	208 + 1/3
6	25	16 + 2/3	41 + 2/3	150	100	250
7–∞	25	15	40	—	—	—

Ensuring that area requirements for all occupant counts are integer multiples of 5 ft²:

Occupant count	Minimum area (ft²)
	Per occupant			Total
	Living	Dining	Total	Living	Dining	Total
1	140	0	140	140	0	140
2	70	0	70	140	0	140
3	40	30	70	120	90	210
4	30	25	55	120	100	220
5–∞	25	20	45	—	—	—