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: scale and dimensions, quantity takeoff, 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 concrete in footing F3
Step 1: find the tag on the plan. F3 sits under the column at grid B-3. Step 2: read its row in the footing schedule, 6'-0" x 6'-0" x 18". Step 3: turn every dimension into feet and multiply, 6 x 6 x 1.5 = 54 cubic feet. Step 4: divide by 27, 54 ÷ 27 = 2.0 cubic yards. Check it another way: 36 square feet of plan area x 1.5 ft = 54, and 27 x 2 = 54.
Example 2: checking a dimension string
Step 1: read the west string on S-101, 20'-0" and 20'-0". Step 2: add it, 20 + 20 = 40. Step 3: compare it with the overall dimension, 40'-0". They agree. Check it against the grid: lines A, B and C are 20 ft apart, so the string and the grid tell the same story. Do this for every string before you take off from it. When a string and its overall disagree, write down both numbers and ask with a request for information (RFI). Do not pick the one that suits your bid.
The three practice sheets
Every sheet is invented for study and labeled as a practice drawing. All three show the same 64 ft by 40 ft building on the same grid, so you can check one sheet against another. The scale notes hold on a full-size print only, so use the written dimensions.
S-101: Foundation plan and footing schedule
Text description of sheet S-101
Practice sheet S-101, foundation plan, scale 3/16 in = 1 ft on a full-size print. Dimensions are to wall and grid centerlines. Grid lines 1 to 5 run west to east at 16 ft spacing and grid lines A to C run north to south at 20 ft spacing. The overall dimensions read 64'-0" east to west and 40'-0" north to south. The north dimension string reads 16'-0", 16'-0", 16'-0" and 16'-0"; the south string reads 16'-0", 16'-0", 16'-0" and 15'-0"; the west string reads 20'-0" and 20'-0". Footing F1 runs under every exterior wall, centered on the wall line. Pads are tagged F2 at B-2, F3 at B-3, F2 at B-4 and F4 at 56 ft east of line 1 and 30 ft south of line A. Footing schedule: F1, continuous wall footing, 24 in wide x continuous x 12 in deep, (3) #4 CONT., top of footing 98'-0"; F2, spread footing, 4'-0" x 4'-0" x 12 in deep, (5) #5 E.W., top of footing 98'-6"; F3, spread footing, 6'-0" x 6'-0" x 18 in deep, (7) #5 E.W., top of footing 98'-0". The schedule has no other rows. Notes: top of slab 100'-0". Slab: 5 in concrete over vapor retarder and 4 in granular base; slab edge at the exterior wall line. CONT. = continuous, E.W. = each way, T.O.F. = top of footing.
S-201: Roof framing plan and member schedule
Text description of sheet S-201
Practice sheet S-201, roof framing plan, scale 1/8 in = 1 ft on a full-size print, same 64'-0" by 40'-0" building and grid as S-101. Ridge beam GL1 runs along line B from line 1 to line 5, on steel columns drawn at B-2, B-3 and B-4; the plan callout reads GL1 5 1/8 x 18 GLULAM. Mono trusses span 20'-0" from the north wall (line A) and from the south wall (line C) up to GL1, drawn at 24 in on center; the plan note reads T1 AT 24 IN O.C., (30) EACH SIDE. A gable end truss sits at each end of each side, on lines 1 and 5. Eaves run along the north and south walls; rakes run along the east and west walls. Roof note: slope 4:12, slope factor 1.054; roof sheathing 7/16 in OSB in 4 ft by 8 ft sheets. Member schedule: T1, mono truss, 20'-0" SPAN, 4:12, 24 in o.c.; T2, gable end truss, 20'-0" SPAN, 4:12, at lines 1 and 5; GL1, glulam ridge beam, 5 1/8 x 16 1/2, line b, 16'-0" spans; C1, steel column, HSS 4 x 4 x 1/4, at b-2, b-3, b-4.
M-101: Reflected ceiling and mechanical plan
Text description of sheet M-101
Practice sheet M-101, reflected ceiling and mechanical plan, scale 1/4 in = 1 ft on a full-size print, same building as S-101. Dimensions are to wall centerlines. Open office 101 is 40'-0" east to west by 40'-0" north to south, ceiling 2x2 ACT at 9'-0" above finished floor, and holds 20 LA, 2 EX, 6 SD-1 and 2 RG-1; Conference 102 is 24'-0" east to west by 20'-0" north to south, ceiling 2x2 ACT at 9'-0" above finished floor, and holds 5 LB, 2 SD-1 and 1 RG-1; Break 103 is 24'-0" east to west by 20'-0" north to south, ceiling GYP. BD. at 8'-6" above finished floor, and holds 6 LC and 1 SD-2. Open Office 101 is the west part of the building; Conference 102 is the northeast room and Break 103 the southeast room. In Open Office 101 the LA troffers run in 4 rows of 5, the SD-1 diffusers in 2 rows of 3, and the two RG-1 grilles sit on the middle line. In Conference 102 an LB sits in each corner area, and one LB and one RG-1 are both drawn in the same center tile, 52 ft east and 10 ft south; the SD-1 diffusers sit north and south of it. Break 103 has 2 rows of 3 LC downlights and one SD-2 in the middle. Fixture schedule: LA, 2x4 led troffer, recessed, 40 W; LB, 2x2 led troffer, recessed, 30 W; LC, 6 in led downlight, 15 W; EX, exit sign, ceiling mounted, 3 W. Diffuser schedule: SD-1, supply, 4-way louvered, face 24 x 24, neck 10 in round, 250 CFM; SD-2, supply, 4-way louvered, face 12 x 12, neck 8 in round, 150 CFM; RG-1, return, perforated, face 24 x 24, neck 22 x 22, no CFM listed. Mechanical note: RTU-1 on the roof supplies 2,000 CFM to the supply diffusers on this sheet. ACT = acoustical ceiling tile, GYP. BD. = gypsum board, A.F.F. = above finished floor.
Practice the arithmetic behind the takeoffs with the concrete yardage calculator and the roofing squares calculator. For a floor plan, a wall section and a site plan, go back to the first plan-reading drill. The NASCLA exam outline shows how the twelve subject areas are weighted.
Ready for more? The third plan-reading drill has three more sheets for one building, a building section, a site utility plan and an electrical and fire protection plan, with 30 questions on elevations, pipe slopes and inverts, schedules and the conflicts between sheets.
NASCLA plan-reading drill 2 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. Six questions ask you to find where a sheet disagrees with itself or with another sheet: a dimension string that does not add up, a tag with no schedule row, a callout that differs from its schedule, a count that differs from its spacing, a supply total that differs from the unit, and two items drawn in one tile. 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.