Answer Key: Self-Test D-1.9

Skilled Trades BC

Answer Key: Self-Test D-1.9

1. Drawing 2P-38 — Drainage

Table 1 Answers
Number	Name	Hydraulic Load (FU)	Size
1	Stack acting as a wet vent	2.5	3 in.
2	Stack	6	3 in.
3	Sanitary building drain	6	4 in. (preferred)
4	Sump discharge	15.85	2 in.
5	Sanitary building drain	21.85	4 in. (preferred)
6	Trap arm — Fixture drain	3	2 in.
7	Stack acting as a wet vent	5.5	3 in.
8	Stack	9	3 in.
9	Fixture drain — Acting as a wet vent	2.5	2 in.
10	Branch	6	3 in.
11	Branch	15	3 in.
12	Sanitary building drain	36.85	4 in. (preferred)
13	Fixture drain — Acting as a wet vent	1	2 in.
14	Branch	6	3 in.
15	Fixture drain	1.5	1.5 in.
16	Trap arm — Fixture drain	3	3 in.
17	Branch	4.5	3 in.
18	Branch	10.5	3 in.
19	Branch	3.5	2 in.
20	Fixture drain — Acting as a wet vent	1.5	1.5 in.
21	Branch	14	3 in.
22	Fixture drain	1.5	1.5 in.
23	Fixture drain	1.5	1.5 in.
24	Branch	3	1.5 in.
25	Sanitary building drain	39.85	4 in. (preferred)

2. Drawing 2P-38 — Venting

Table 2 Answers
Letter	Name	Hydraulic Load (FU)	Length	Size
A	Continuous vent	6	36 m	2 in.
B	Individual and continuous vent	N/A	N/A	1.25 in.
C	Branch vent	7.5	36 m	2 in.
D	Continuous vent	3.5	18 m	1.5 in.
E	Branch vent	11	36 m	2 in.
F	Sump vent	N/A	N/A	2 in.
G	Branch vent	27	36 m	3 in.
H	Island vent (air admittance valve)	1.5	N/A	1.25 in.
I	Individual and continuous vent	N/A	N/A	1.25 in.
J	Continuous vent	6	9 m	1.5 in.
K	Branch vent	7.5	13 m	1.5 in.
L	Stack vent	9	11 m	1.5 in.
M	Stack vent	16.5	11 m	2 in.
N	Stack vent (Clause 2.5.8.4 (5))	6	7 m	3 in.
O	Vent header	49.5	38 m	3 in.

3. Drawing 2P-39 — Drainage

Table 3 Answers
Number	Name	Hydraulic Load (FU)	Size
1	Trap arm — Fixture drain	1	1.25 in.
2	Stack acting as a wet vent	2.5	3 in.
3	Stack	6	3 in.
4	Fixture drain	1.5	1.5 in.
5	Branch	3	1.5 in.
6	Branch	4.5	2 in.
7	Stack	10.5	3 in.
8	Trap arm — Fixture drain	1.5	1.5 in.
9	Branch	4.5	2 in.
10	Branch	9	2.5 in.
11	Stack	19.5	3 in.
12	Sanitary building drain	19.5	4 in. Preferred
13	Trap arm — Fixture drain	N/A	3 in.
14	Sanitary building drain	19.5	4 in. Preferred
15	Stack acting as a wet vent	1	2 in.
16	Stack	8	3 in.
17	Sanitary building drain	27.5	4 in.
18	Fixture drain acting as a wet vent	1	2 in.
19	Branch	5	3 in.
20	Sanitary building drain	32.5	4 in.

4. Drawing 2P-39 — Venting

Table 4 Answers
Letter	Name	Hydraulic Load (FU)	Length	Size
A	Continuous vent	5	15 m	1.5 in.
B	Individual vent	N/A	N/A	1.5 in.
C	Stack vent	8	22 m	2 in.
D	Stack vent	8	22 m	2 in.
E	Stack vent	13	22 m	2 in.
F	Circuit vent	9	9 m	1.5 in.
G	Relief vent	N/A	N/A	1.25 in.
H	Branch vent	9	15 m	1.5 in.
I	Stack vent	22	22 m	2 in.
J	Individual and continuous vent	N/A	N/A	1.25 in.
K	Dual and continuous vent	N/A	N/A	1.25 in.
L	Branch vent	4.5	5 m	1.25 in.
M	Stack vent	26.5	22 m	2 in.
N	Stack vent	19.5	3 m	3 in.
O	Vent header	32.5	31 m	3 in.

5. Drawing 2P-40 — Drainage

Table 5 Answers
Number	Name	Hydraulic Load (FU)	Size
1	Stack	16	3 in.
2	Stack	17	3 in.
3	Branch	30	4 in.
4	Branch	42	4 in.
5	Stack	59	4 in.
6	Stack (Offset)	59	4 in.
7	Branch	4	2 in.
8	Stack	63	4 in.
9	Stack acting as a wet vent	2.5	2 in.
10	Stack	8	3 in.
11	Stack (Offset)	8	3 in.
12	Fixture drain	0.5	1.25 in.
13	Stack	8.5	3 in.
14	Branch	8.5	3 in.
15	Vent stack acting as a fixture drain sized as a wet vent	1.59	3 in.
16	Stack	73.09	4 in.
17	Sanitary building drain	73.09	4 in.

6. Drawing 2P-40 — Venting

Table 6 Answers
Letter	Name	Hydraulic Load (FU)	Length	Size
A	Vent stack	73.09	35 m	3 in.
B	Individual and continuous vent	N/A	N/A	1.25 in.
C	Branch vent	1.5	15 m	1.5 in.
D	Branch vent	4.5	15 m	1.5 in.
E	Vent stack	73.09	35 m	3 in.
F	Individual vent	N/A	N/A	1.25 in.
G	Relief vent	N/A	N/A	1.5 in.
H	Branch vent	43	11 m	2 in.
I	Circuit vent	42	2 m	1.5 in.
J	Branch vent	43	11 m	2 in.
K	Vent stack	73.09	35 m	3 in.
L	Stack vent	8.5	10 m	1.5 in.
M	Stack vent	73.09	3 m	2 in.
N	Vent header	73.09	10 m	2 in.

7. Drawing 2P-41 —Drainage

Table 7 Answers
Number	Name	Hydraulic Load (FU)	Size
1	Stack acting as a wet vent	5	3 in.
2	Stack acting as a wet vent	5	3 in.
3	Branch	6.5	3 in.
4	Stack	18	3 in.
5	Stack	35.27	3 in.
6	Fixture drain acting as a wet vent	1	2 in.
7	Branch	13	3 in.
8	Stack	58.27	4 in.
9	Branch	61	4 in.
10	Stack	131.27	4 in.
11	Branch	8	3 in.
12	Stack	147.77	4 in.
13	Sanitary building drain	154.27	4 in.
14	Stack	7	3 in.
15	Branch	8	3 in.
16	Branch	8.5	3 in.
17	Stack	56.92	4 in.
18	Sanitary building drain	211.19	4 in.

8. Drawing 2P-41 — Venting

Table 8 Answers
Letter	Name	Hydraulic Load (FU)	Length	Size
A	Individual vent	N/A	N/A	1.5 in.
B	Individual and continuous vent	N/A	N/A	1.25 in.
C	Continuous vent	8	21 m	1.5 in.
D	Branch vent	8.5	21 m	2 in.
E	Branch vent	46.92	21 m	3 in.
F	Continuous vent	3	18 m	1.5 in.
G	Branch vent	49.92	21 m	3 in.
H	Branch vent	2.5	13 m	1.5 in.
I	Branch vent	52.42	21 m	3 in.
J	Branch vent	58.92	21 m	3 in.
K	Continuous vent	9.27	7 m	1.5 in.
L	Branch vent	68.19	21 m	3 in.
M	Stack vent	56.92	9 m	3 in.
N	Continuous vent	8	14 m	1.5 in.
O	Branch vent	16.5	14 m	1.5 in.
P	Vent stack	147.77	26 m	3 in.
Q	Vent stack	147.77	26 m	3 in.
R	Fixture drain acting as an additional circuit vent sized as a wet vent	N/A	N/A	2 in.
S	Vent stack	148.77	26 m	3 in.
T	Circuit vent	73	1 m	2 in.
U	Individual and continuous vent acting as a relief vent	N/A	N/A	1.5 in.
V	Branch vent	14	5 m	1.5 in.
W	Continuous vent	10	3 m	1.5 in.
X	Branch vent	18	5 m	1.5 in.
Y	Stack vent	147.77	3 m	2 in.
Z	Stack vent	6.5	3 m	3 in.

9. Drawing 2P-42 — Drainage

Table 9 Answers
Number	Name	Hydraulic Load (FU)	Size
1	Stack acting as a wet vent	2	3 in.
2	Stack	9	3 in.
3	Branch	2	1.5 in.
4	Branch	4	2 in.
5	Branch	6	2 in.
6	Branch	18	3 in.
7	Fixture drain acting as a wet vent	2.5	2 in.
8	Stack	31	3 in.
9	Branch	8	3 in.
10	Stack	39	3 in.
11	Stack acting as a wet vent	3.5	2 in.
12	Stack acting as a wet vent	4.44	3 in.
13	Branch	6.66	3 in.
14	Stack	12.66	3 in.
15	Branch	12.66	3 in.
16	Fixture drain acting as a wet vent	2.5	2 in.
17	Branch — Wet vent	2.5	2 in.
18	Branch	16	3 in.
19	Stack	67.66	3 in.
20	Sanitary building drain	67.66	4 in.
21	Fixture drain	3	2 in.
22	Branch	18	3 in.
23	Sanitary building drain	85.66	4 in.

10. Drawing 2P-42 — Venting

Table 10 Answers
Letter	Name	Hydraulic Load (FU)	Length	Size
A	Individual and continuous vent	N/A	N/A	1.5 in.
B	Branch vent	9	12 m	1.5 in.
C	Individual and continuous vent	N/A	N/A	1.5 in.
D	Branch vent	18	12 m	1.5 in.
E	Vent stack	67.66	18 m	2 in.
F	Vent stack	85.66	18 m	2 in.
G	Continuous vent	8	16 m	1.5 in.
H	Continuous vent	8	14 m	1.5 in.
I	Branch vent	16	16 m	2 in.
J	Continuous vent	8	4 m	1.5 in.
K	Branch vent	24	16 m	2 in.
L	Dual and continuous vent	N/A	N/A	1.5 in.
M	Branch vent	12	9 m	1.5 in.
N	Branch vent	18	9 m	1.5 in.
O	Vent stack	85.66	18 m	2 in.
P	Stack vent	67.66	3 m	3 in.
Q	Vent header	85.66	26 m	3 in.
R	Continuous vent	4	3 m	1.25 in.
S	Stack vent	12.66	2 m	1.5 in.
T	Stack vent	6.66	2 m	1.5 in.

11. Drawing 2P-43 — Drainage

Table 11 Answers
Number	Name	Hydraulic Load (FU)	Size
1	Stack	10	3 in.
2	Fixture drain acting as a wet vent	4	3 in.
3	Branch	12	3 in.
4	Stack	22	3 in.
5	Fixture drain acting as a circuit vent sized as a wet vent	1	2 in.
6	Stack	44	4 in.
7	Stack	51	4 in.
8	Branch	3	1.5 in.
9	Stack	54	4 in.
10	Branch — Wet vent	2.5	2 in.
11	Stack	60.5	4 in.
12	Sanitary building drain	60.5	4 in.
13	Stack acting as a wet vent	2.5	3 in.
14	Stack	6	3 in.
15	Fixture drain acting as a wet vent	1	1.5 in.
16	Branch	2.5	1.5 in.
17	Fixture drain acting as a wet vent	1	2 in.
18	Stack	32	4 in.
19	Branch	20	4 in.
20	Stack	68	4 in.
21	Branch	12	3 in.
22	Vent stack acting as a branch sized as a wet vent	2.59	3 in.
23	Stack	82.59	4 in.
24	Sanitary building drain	143.09	4 in.

12. Drawing 2P-43 — Venting

Table 12 Answers
Letter	Name	Hydraulic Load (FU)	Length	Size
A	Circuit vent	12	8 m	1.5 in.
B	Branch vent	12	8 m	1.5 in.
C	Vent stack	82.59	33 m	3 in.
D	Circuit vent	36	14 m	2 in.
E	Relief vent	N/A	N/A	1.5 in.
F	Branch vent	36	14 m	2 in.
G	Continuous vent	6	8 m	1.5 in.
H	Continuous vent	2.5	4 m	1.25 in.
I	Individual vent	N/A	N/A	1.5 in.
J	Branch vent	4.5	8 m	1.5 in.
K	Stack vent	82.59	21 m	3 in.
L	Vent header	82.59	40 m	3 in.
M	Relief vent	N/A	N/A	1.5 in.
N	Branch vent	13	14 m	1.5 in.
O	Vent header	82.59	40 m	3 in.
P	Continuous vent	6	4 m	1.5 in.
Q	Vent stack	60.5	24 m	3 in.
R	Vent stack	60.5	24 m	3 in.
S	Dual and continuous vent	N/A	N/A	1.25 in.
T	Continuous vent	7	2 m	1.5 in.
U	Circuit vent	21	7 m	1.5 in.
V	Branch vent	22	7 m	1.5 in.
W	Continuous vent	5	2 m	1.5 in.
X	Stack vent	60.5	9 m	3 in.
Y	Vent header	60.5	25 m	3 in.
Z	Vent header	143.09	40 m	3 in.

13. Drawing 2P-44 — Drainage

Table 13 Answers
Number	Name	Hydraulic Load (FU)	Size
1	Branch	10	2.5 in.
2	Branch	9	3 in.
3	Stack	19	4 in.
4	Branch	8	2.5 in.
5	Branch	10	4 in.
6	Branch	34	4 in.
7	Branch	18	3 in.
8	Branch	32	4 in.
9	Stack acting as a wet vent	6	3 in.
10	Branch	7.5	3 in.
11	Branch	36	4 in.
12	Branch	108	4 in.
13	Branch	120	4 in.
14	Stack	242.5	5 in.
15	Sanitary building drain	242.5	5 in.
16	Trap arm — Fixture drain	2	2 in.
17	Branch	8	2.5 in.
18	Stack	69	4 in.
19	Stack acting as a wet vent	6	3 in.
20	Trap arm — Fixture drain	6	3 in.

14. Drawing 2P-44 — Venting

Table 14 Answers
Letter	Name	Hydraulic Load (FU)	Length	Size
A	Vent stack	242.5	30 m	4 in.
B	Circuit vent	120	21 m	3 in.
C	Additional circuit vent	N/A	N/A	2 in.
D	Branch vent	120	21 m	3 in.
E	Branch vent	14	7 m	1.5 in.
F	Vent stack	242.5	30 m	4 in.
G	Circuit vent	30	13 m	2 in.
H	Dual and continuous vent acting as a relief cent	N/A	N/A	1.5 in.
I	Circuit vent	32	14 m	2 in.
J	Branch vent	35	14 m	2 in.
K	Vent stack	242.5	30 m	4 in.
L	Continuous vent	7	8 m	1.5 in.
M	Dual and continuous vent	N/A	N/A	1.5 in.
N	Stack vent	242.5	5 m	3 in.
O	Vent header	242.5	45 m	4 in.
P	Branch vent	15	8 m	1.5 in.
Q	Stack vent	7.5	7 m	3 in.
R	Branch vent	19	12 m	1.5 in.

15. Drawing 2P-45 — Drainage

Table 15 Answers
Number	Name	Hydraulic Load (FU)	Size
1	Stack	10	3 in.
2	Fixture drain acting as a wet vent	2.5	2 in.
3	Branch	6	3 in.
4	Stack	19	3 in.
5	Fixture drain acting as a wet vent	0.5	2 in.
6	Stack	23.5	3 in.
7	Stack	30.5	3 in.
8	Branch	8	2.5 in.
9	Stack	38.5	3 in.
10	Branch — Wet vent	1.5	2 in.
11	Stack	45.5	3 in.
12	Sanitary building drain	45.5	4 in.
13	Branch	85	4 in.
14	Sanitary building drain	130.5	4 in.
15	Stack acting as a wet vent	1	2 in.
16	Stack	5	3 in.
17	Stack	8	3 in.
18	Branch — Wet vent	2	1.5 in.
19	Branch	3.5	2 in.
20	Stack	11.5	3 in.
21	Fixture drain acting as a wet vent	1	2 in.
22	Stack	17.5	3 in.
23	Branch	20	4 in.
24	Stack	53.5	4 in.
25	Branch	12	3 in.
26	Vent stack acting as a fixture drain sized as a wet vent	1.5	3 in.
27	Stack	67	4 in.
28	Sanitary building drain	197.5	5 in.

16. Drawing 2P-45 — Venting

Table 16 Answers
Letter	Name	Hydraulic Load (FU)	Length	Size
A	Circuit vent	12	8.5 m	1.5 in.
B	Branch vent	12	8.5 m	1.5 in.
C	Vent stack	67	42 m	3 in.
D	Vent stack	67	42 m	3 in.
E	Circuit vent	36	11 m	2 in.
F	Relief vent	N/A	N/A	1.5 in.
G	Branch vent	36	11 m	2 in.
H	Vent stack	67	42 m	3 in.
I	Continuous vent	6	9 m	1.5 in.
J	Vent stack	67	42 m	3 in.
K	Continuous vent	3.5	5.5 m	1.25 in.
L	Vent stack	67	42 m	3 in.
M	Individual vent	N/A	N/A	1.5 in.
N	Branch vent	3	8.5 m	1.5 in.
O	Vent stack	67	42 m	3 in.
P	Stack vent	67	8 m	2 in.
Q	Vent header	67	48.5 m	3 in.
R	Continuous vent	5.5	3 m	1.5 in.
S	Vent stack	45.5	30.2 m	3 in.
T	Vent stack	45.5	30.2 m	3 in.
U	Dual and continuous vent	N/A	N/A	1.5 in.
V	Vent stack	45.5	30.2 m	3 in.
W	Continuous vent	7	4 m	1.5 in.
X	Vent stack	45.5	30.2 m	3 in.
Y	Continuous vent	4.5	9 m	1.5 in.
Z	Vent stack acting as a fixture sized as a wet vent	1.5	30.2 m	3 in.
AA	Vent stack	45.5	30.2 m	3 in.
AB	Continuous vent	6	5 m	1.5 in.
AC	Vent stack	45.5	30.2 m	3 in.
AD	Continuous vent	5	1 m	1.5 in.
AE	Stack vent	45.5	5.7 m	1.5 in.
AF	Continuous vent	5	1 m	1.5 in.
AG	Stack vent	45.5	5.7 m	1.5 in.
AH	Vent header	45.5	28.2 m	3 in.

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