NASCLA plan-reading drill 3: sections, site utilities and power

Read three more original practice sheets, a building section, a site utility plan and an electrical and fire protection plan, and answer 30 questions on takeoff, slopes and inverts, schedules and coordination conflicts.

Three practice sheets · 30 questions

NASCLA plan-reading drill 3

See all three sheets ↓

Each question shows the sheet it is about. Read the answer off the drawing, its dimensions, tags and schedules, and work any arithmetic. Some questions ask you to find where two parts of the set disagree. Every answer shows the working and what each wrong option got wrong.

Set 20261109 · 0 of 30 answered · 0 correct

Question 1 of 30 · sheet C-201

EX. STORM MAINEX. SAN. MAINBUILDINGSEE A-301CB-1CB-2MH-1CO-1SMH-1SMH-2P1P2P3P4P5P6CROSSINGSTORMSANITARYNPIPE TABLERUNFROMTOSIZEMATL.LENGTHSLOPEP1CB-1CB-212 INRCP120 LF0.50%P2CB-2MH-115 INRCP80 LF0.50%P3MH-1EX. STORM15 INRCP60 LF1.00%P4CO-1SMH-16 INPVC60 LF2.00%P5SMH-1SMH-28 INPVC100 LF1.00%P6SMH-2EX. SAN8 INPVC60 LF-STRUCTURE TABLESTR.TYPERIMINV. ININV. OUTCB-1CATCH BASIN98.50-96.00CB-2CATCH BASIN98.4095.4095.30MH-1STORM MANHOLE98.8094.9094.80CO-1CLEANOUT--97.20SMH-1SAN. MANHOLE99.0096.0095.90SMH-2SAN. MANHOLE98.6094.9094.801. CONNECT P3 TO EX. STORM MAIN AT INV. 94.50.2. CONNECT P6 TO EX. SAN. MAIN AT INV. 93.90.3. P1 CROSSES P5 40 FT DOWNSTREAM OF CB-1 AND 50 FT DOWNSTREAM OF SMH-1.4. TRENCH WIDTH 3'-0". ELEVATIONS IN FEET; INV. = FLOW LINE.RCP = REINFORCED CONCRETE PIPE · PVC = POLYVINYL CHLORIDEPRACTICE DRAWING, INVENTED FOR STUDY. NOT FOR CONSTRUCTION.SITE UTILITY PLANSCALE 1 IN = 40 FT ON A FULL-SIZE PRINTC-201
Text description of sheet C-201

Practice sheet C-201, site utility plan, scale 1 in = 40 ft on a full-size print. Elevations are in feet; inverts are pipe flow lines. The building, the same 60'-0" by 40'-0" building as A-301, sits at the north of the lot. Storm: catch basin CB-1 east of the building drains west through P1 to CB-2, then south through P2 to storm manhole MH-1, then west through P3 to the existing storm main in the west street, connecting at invert 94.50. Sanitary: cleanout CO-1 at the east wall drains east through P4 to manhole SMH-1, then south through P5 to SMH-2, then south through P6 to the existing sanitary main in the south street, connecting at invert 93.90. Plan note: P1 crosses P5 40 ft downstream of CB-1 and 50 ft downstream of SMH-1. Trench width 3'-0". Pipe table: P1, CB-1 to CB-2, 12 in RCP, 120 LF, slope 0.50%; P2, CB-2 to MH-1, 15 in RCP, 80 LF, slope 0.50%; P3, MH-1 to EX. STORM, 15 in RCP, 60 LF, slope 1.00%; P4, CO-1 to SMH-1, 6 in PVC, 60 LF, slope 2.00%; P5, SMH-1 to SMH-2, 8 in PVC, 100 LF, slope 1.00%; P6, SMH-2 to EX. SAN, 8 in PVC, 60 LF, slope not given. Structure table: CB-1, catch basin, rim 98.50, invert in none, invert out 96.00; CB-2, catch basin, rim 98.40, invert in 95.40, invert out 95.30; MH-1, storm manhole, rim 98.80, invert in 94.90, invert out 94.80; CO-1, cleanout, rim not given, invert in none, invert out 97.20; SMH-1, san. manhole, rim 99.00, invert in 96.00, invert out 95.90; SMH-2, san. manhole, rim 98.60, invert in 94.90, invert out 94.80. RCP = reinforced concrete pipe, PVC = polyvinyl chloride pipe, LF = linear feet, EX. = existing.

The plan note says P1 crosses P5 50 ft downstream of SMH-1. What is the invert of P5 at the crossing?

This is the third set of practice sheets. The first plan-reading drill covers a floor plan, a wall section and a site plan, and the second a foundation plan, a roof framing plan and a reflected ceiling plan. This one adds a building section, site utilities and a power and sprinkler plan, where much of the work is elevation and slope arithmetic, and asks you to catch where the sheets disagree. For what the bulletin does and does not say about the packet handed out at the test center, read the NASCLA diagram and blueprint packet guide.

How the drill works

Each set serves all 30 questions in a shuffled order, with the four options shuffled too. Each question shows the sheet it is about, and every sheet has a text description with all of its values, so you can work it without seeing the drawing. On a phone the sheet runs the full width of the screen; tap a sheet or its zoom button to read it at twice the size, then drag to move around it. Check your answer and the explanation shows where on the sheet to look, the arithmetic worked twice, and the slip behind each wrong option.

Your score is one point per question, out of 30. At the end you see your misses by skill: quantity takeoff, slope, invert and elevation arithmetic, schedule lookup, coordination conflicts. Hit New shuffle for a fresh order. Use the set number if you report an error.

Worked examples

Example 1: the slope of pipe P2 from its inverts

Step 1: find the run on C-201. P2 runs from CB-2 south to MH-1. Step 2: read the structure table, CB-2 invert out 95.30 and MH-1 invert in 94.90. Step 3: subtract for the fall, 95.30 - 94.90 = 0.40 ft. Step 4: divide by the 80 LF in the pipe table, 0.40 ÷ 80 = 0.005, or 0.50%. That matches the table. Check it the other way: 80 x 0.50% = 0.40 ft, and 95.30 - 0.40 = 94.90.

Example 2: will the Level 2 ceilings fit?

Step 1: read the floor-to-floor string on A-301, 12'-8" from Level 2 to Level 3. Step 2: take off the structure, 2'-6" from top of slab to underside of joists, leaving 10'-2". Step 3: compare it with the 9'-0" ceilings the finish schedule gives Office 201 and File 202. They fit, with 1'-2" left for ducts and pipes. Check it by elevation: Level 3 at 126'-8" less 2'-6" is 124'-2", and the ceilings sit at 114'-0" + 9'-0" = 123'-0", 1'-2" lower. Do this for every room. When a ceiling does not fit, write down both numbers and ask with a request for information (RFI).

The three practice sheets

Every sheet is invented for study and labeled as a practice drawing. All three show the same 60 ft by 40 ft building, so you can check one sheet against another. The scale notes hold on a full-size print only, so use the written dimensions.

Practice the arithmetic behind the trench and cubic-yard takeoffs with the cut and fill calculator and the concrete yardage calculator. For a floor plan, a wall section and a site plan, go back to the first plan-reading drill; for foundations, roof framing and ceilings, the second. The NASCLA exam outline shows how the twelve subject areas are weighted.

NASCLA plan-reading drill 3 FAQ

Are these sheets like the packet handed out at the test center?

We cannot say, and we do not claim they are. PSI's bulletin lists a physical diagram/blueprint packet to be handed out onsite at the testing center and says nothing about what is in it. We have not seen it. These three sheets are our own invented practice drawings, built to practice reading drawings in general.

Why do some sheets have mistakes on them?

On purpose. Seven questions ask you to find where a sheet disagrees with itself: a level tag that differs from its dimension, a ceiling scheduled higher than the structure allows, a pipe slope that differs from its inverts, two pipes that cross at the same elevation, a receptacle on a spare circuit, a load larger than its breaker, and a light drawn on a sprinkler head. Real drawing sets carry slips like these. The habit is to check, write down both numbers and ask, not to pick one.

How do I read the sheets on a phone?

Each sheet runs the full width of the screen and is drawn so its text is close to full size there. Tap a sheet or its zoom button to read it at twice the size, then drag to move around it. Every sheet also has a text description with all of its values. Do not measure the screen: the scale notes hold only on a full-size print, so questions that need a measurement give it to you.

30 original questions on three invented practice sheets for one building: a building section with a finish schedule, a site utility plan with pipe and structure tables and an electrical and fire protection plan with a panel schedule and sprinkler heads. Every answer comes from the drawing alone, is worked twice and says what each wrong option got wrong. No exam item or reference text is used.

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