3D viewOrbit the frame
Orbit, snap to views, export to glTF.
The 3D view draws the same 150 solids the plan, the iso and the cut list come from. There is no second model to keep in step.
- Solids
- 150
- Footprint
- 27'-2" × 34'-7"
A-000 · Cover
Every 2×10
accounted for.
Describe your build once. 2by draws the framing plans, checks the spans, and writes the cut list and shopping list, and keeps every one of them in sync when the design changes.
Project
Freestanding Timber Loft
Sheet
A-000
Rev
r28 · NTS
A-001 · The design always changes
The design always changes.
2by started with one real loft design. While it was being drawn, a beam changed type, posts were added, a beam was deleted, the stair opening moved. Every change rippled through the parts list, and several changed it in more than one place.
The list was kept by hand, so it was re-counted by hand. Every time.
was 3-ply 2×12 beam, now 2-ply LVL- 22 pcs 2×8
- + 2 postsshorter spans, less money
was interior beam, now deleted19 joists re-orientedwas notched joint, now hung jointbeam re-routedwas stair opening, now moved 6"header, landing, joist countwas post, now 4×4new base hardware, new concrete detailwas double 2×10 beam, now single rim joistcarries no load- Summary: Every piece of lumber on the job is 2×10.
At one point the summary said every piece of lumber on the job was 2×10, while a line 40 lines above it listed 22 pieces of 2×8.
A parts list is a derived document.
Stop writing it by hand.
Keeping a derived document by hand guarantees drift. 2by keeps one model of the structure and derives the list from it, so the list and the design cannot disagree.
A-100 · How it works
One model. Every document.
You describe the building once, as a plain-text model. The drawings, the checks and the lists are all derived from it. Change one value and every one of them follows.
joist_fields: - id: CATWALK label: Catwalk section: 2x10 span_axis: x bounds_x: [2-3/4", 9'-9-1/4"] bounds_y: [12, 34'-4-1/4"] framing: drop hung_at: [WALL-TRACK] cantilever_ft: { INNER-TRACK: 2 } spacing_in: 16 hanger: LUS210 bears_on: [WALL-TRACK, INNER-TRACK] blocking: true phase: p2Line 596, the model’s own comment: # was 2x8; INNER-TRACK drops a full 2x10 so the deck stays level
Plan
2×10 @ 16" o.c.
catwalk joists, labelled from the model
was 2×8 @ 16" o.c.
Elevations
9¼" deep
joist depth, drawn to size
was 7¼" deep
Isometric
150 solids
painter-sorted, redrawn
3D view
85 pieces
members in the model
was 87 pieces
Sheets
14 sheet types
S-6, S-7, S-8 re-issued
Findings
0 errors
bending 67% · L/1020
was 2 errors · bending 93% · L/496
Joist field CATWALK bears on members whose tops differ by 0'-2".LUS210 does not fit CATWALK joists hung at WALL-TRACK
Cut list
85 sticks
catwalk: 25 × 2×10
was 87 sticks · catwalk: 8 × 2×10 + 19 × 2×8
Shopping list
38 lines
lumber order: 21 rows
was 41 lines · lumber order: 25 rows
Hardware
17 × LUS210
catwalk: hangers fit the joist
was catwalk: hangers do not fit the joist
Build log
38 tasks
re-derived, in build order
was 40 tasks
Line 596: section 2×8 → 2×10. Both versions derived by the tool: bending 93% → 67%, deflection L/496 → L/1020, errors 2 → 0. It computes and flags; a person approves.
S-201 · 3D model
One model. Every view.
The 3D view is not a separate model. It is drawn from the same solids as the framing plan and the cut list for the Freestanding Timber Loft (r28), so it cannot show a building the drawings don’t.
Section planesCut through it
Slice anywhere to see how it goes together.
A cutting plane sweeps through the loft. The members it passes through light up, so you can see what bears on what: joists on beams, beams on posts.
- Posts
- 13
- Beams
- 11
- Joists
- 38
ExplodeTake it apart in build order
See every member in the order it’s built.
The layers lift apart from the top down and settle back from the bottom up: footings, posts, floor and deck. The order is the one the drawings use.
- FOOTINGS
- 4
- POSTS
- 13
- FLOOR
- 19
- DECK
- 4
- 00 FOOTINGS
- 01 POSTS
- 02 FLOOR
- 03 DECK
MeasureMeasure between real corners
Measure anything, snapped to real geometry.
Pick two points and each one snaps to a member corner. Here it is the clear span between posts P6 and P7: 13'-0-1/2".
- From
- P6 · 6x6
- To
- P7 · 6x6
- Clear
- 13'-0-1/2"
DrawingsThe same model, drawn flat
Plans, elevations and isometric views, drawn from the same model.
Look straight down and the model becomes the framing plan: the same members, the same ids, the same revision. Change the model and every view redraws.
- Model
- Freestanding Timber Loft
- Revision
- r28
S-301 · It checks the structure
It checks the structure.
Every beam and joist field is checked for bending and deflection under the loads in the model: 50 psf live, 10 psf dead. Every post base is checked against its catalogue rating. A check that is close to its limit is flagged, not rounded away.
- Span checks
- 9
- Errors
- 0
- Warnings
- 1
- Notes
- 40
Back beam
2-ply 2x10
- Span
- 8'-11-3/4" (worst of 3)
- Load
- 277 plf
- Bending
- 98% of allowable
- Deflection
- 0.15" · L/737
WatchBending 98%
LVL header (drop beam)
2-ply LVL-11.875
- Span
- 13'-6" (worst of 2)
- Load
- 433 plf + INNER-TRACK
- Bending
- 48% of allowable
- Deflection
- 0.32" · L/513
PassDeflection L/513
Stair landing
2x10 @ 16" o.c.
- Span
- 9'-7-3/4"
- Load
- 83 plf
- Bending
- 68% of allowable
- Deflection
- 0.12" · L/987
PassDeflection L/987
Catwalk wall track
2-ply 2x10
- Span
- 8'-6-3/4" (worst of 3)
- Load
- 277 plf
- Bending
- 89% of allowable
- Deflection
- 0.12" · L/850
PassBending 89%
P6 carried more than its base was rated for. The next revision fixed it.
- r25ABA66Z · 12,673 lb on a base rated 11,415 lbFail111% of rating
- r26ABU66Z · 12,673 lb on a base rated 18,205 lbPass70% of rating
Both rows are the saved model files for r25 and r26, run through today’s checks. The load did not change; the part did.
Stair: open risers leave 7-1/2" between treads, enough to pass a 4" sphere.
Flagged for review. The model marks it deliberate on a shop stair. 13 riser boards close the gap if the loft becomes living space.
Warn1 open warning
Cited to the printed page
Lumber design values and connector ratings are cited to the published tables they came from. A value is marked verified only after someone has read it on the printed page. At r28: 6 of 6 connector types this model relies on are marked verified, and 11 of 11 lumber entries.
- Boise CascadeVERSA-LAM Specifier Guidepp. 27–301 extract on file
- LPLegacy Premium Subflooring1 extract on file
- AWCNDS SupplementTable 4D Southern Pine1 extract on file
- Simpson Strong-TieWood Construction Connectors C-C-2026pp. 114–118, 158–164, 290–291, 299–3014 extracts on file
C-401 · Ready for the lumber yard
Cut lists nested to the lengths your yard stocks
The Freestanding Timber Loft cuts into 85 sticks across 10 cut-list rows. Every piece is packed onto a stock board, and the tool keeps whichever stock length buys the fewest total feet. The shopping list and the hardware schedule are counted from the same model, so they agree with the drawings.
2×10North Platform30 sticks10'-0" / 12'-0"waste 3%
- Stick 1 of 30, 12'-0" of 2×10: cuts 11'-9"; offcut 0'-3".
- Stick 18 of 30, 12'-0" of 2×10: cuts 9'-6-1/2" + 1'-2-1/2" + 1'-2-1/2"; offcut 0'-0-1/2".
- Stick 19 of 30, 12'-0" of 2×10: cuts 9'-6" + 1'-2-1/2" + 1'-2-1/2"; offcut 0'-1".
- Stick 23 of 30, 12'-0" of 2×10: cuts 9'-2-1/2" + 1'-2-1/2" + 1'-2-1/2"; offcut 0'-4-1/2".
- Stick 25 of 30, 12'-0" of 2×10: cuts 8'-11-3/4" + 1'-2-1/2" + 1'-2-1/2"; offcut 0'-7-1/4".
- Stick 28 of 30, 10'-0" of 2×10: cuts 8'-11-3/4"; offcut 1'-0-1/4".
+ 24 more sticks in this row
6×6North Platform6 sticks8'-0" / 10'-0"waste 8%
- Stick 1 of 6, 10'-0" of 6×6: cuts 8'-8-1/4"; offcut 1'-3-3/4".
- Stick 2 of 6, 10'-0" of 6×6: cuts 8'-8-1/4"; offcut 1'-3-3/4".
- Stick 3 of 6, 10'-0" of 6×6: cuts 8'-8-1/4"; offcut 1'-3-3/4".
- Stick 4 of 6, 8'-0" of 6×6: cuts 7'-11"; offcut 0'-1".
- Stick 5 of 6, 8'-0" of 6×6: cuts 7'-11"; offcut 0'-1".
- Stick 6 of 6, 8'-0" of 6×6: cuts 7'-11"; offcut 0'-1".
LVL-11.875North Platform2 sticks28'-0"waste 3%
- Stick 1 of 2, 28'-0" of LVL-11.875: cuts 13'-6" + 13'-6"; offcut 1'-0".
- Stick 2 of 2, 28'-0" of LVL-11.875: cuts 9'-9-1/4" + 9'-9-1/4" + 3'-10-3/4" + 3'-10-3/4"; offcut 0'-8".
2×4Stair1 stick8'-0"waste 59%
- Stick 1 of 1, 8'-0" of 2×4: cuts 3'-3"; offcut 4'-9".
Shopping listr28
Freestanding Timber LoftWhole job · 38 lines
Lumber & sheet goods13 lines
| Quantity | Item |
|---|---|
| 8 pcs | 2×6 post, PT · 10'-0" |
| 5 pcs | 6×6 post, PT · 8'-0" |
| 6 pcs | 6×6 post, PT · 10'-0" |
| 54 pcs | 2×10 · 12'-0" |
| 3 pcs | 2×12 · 16'-0" |
| 23 sheets | T&G subfloor · 3/4" × 4' × 8' sheet |
+ 7 more lines
Hardware & fasteners21 lines
| Quantity | Item |
|---|---|
| 28 ea | 1/2" × 6-1/2" through-bolt set |
| 38 ea | H2.5A |
| 39 ea | LUS210 |
| 156 ea | SDWS FRAMING 0.160 x 3 |
+ 17 more lines
Concrete & rebar4 lines
| Quantity | Item |
|---|---|
| 30 bags | Concrete, 80 lb bags (4,000 psi) · 16.3 cu ft + 10% |
| 10 bags | Concrete, 80 lb bags (4,000 psi) · 5.4 cu ft + 10% |
+ 2 more lines
38 linesUnit prices: yours to enter
Showing 12 of the 38 lines the tool prints for this model.
Hardware schedule
Each connector is picked from the hardware catalog for the member it carries and the load at that end. A part the catalog cannot rate is flagged, not guessed.
- ABA66Zpost base10 eachrated 11,415 lb
- ABA46Zpost base2 eachrated 10,500 lb
- ABU66Zpost base1 eachrated 18,205 lb
- HHUS410girder hanger1 eachrated 5,635 lb
- LUS210joist hanger39 eachrated 1,335 lb
- H2.5Aframing tie38 each
G-001 · The drawing set
33 sheets, printed from one model
The SHEETS button builds the whole set on letter paper: plans, elevations, details, schedules and the review notes. Every page is drawn from the same model as the screen, so a beam that changes on the plan changes on the cut list and the order list too.
- Sheets
- 33
- Sheet types
- 14
- Post + footing
- 9
Shown: the Freestanding Timber Loft, r28. The set prints in English or Spanish. Pick a sheet from the index to bring it to the top.
Sheets in this set
G-002 · From plan to build
Every change is recorded. The task list follows.
The loft went through 5 saved revisions, r24 to r28. Each card is the saved model file, run through today’s checks and compared with the one before it. The build log is derived from the model in the order the building goes together, so when a revision adds a stair, the stair gets its own tasks.
Captions are quoted from the project’s engineering log.
- r24
P13 deleted.
- Pieces
- 74
- Tasks
- 42
- Errors
- 7
- Warnings
- 0
Earliest saved revision
13 posts · 11 beams · 39 joists
- r25+1 day
East and south posts pulled in to the rails.
- Pieces
- 72 (−2)
- Tasks
- 42
- Errors
- 7
- Warnings
- 3 (+3)
Changed from r24
- P4 moved (x)
27'-2"→ 27'-0-1/4" - P8 moved (x)
27'-2"→ 27'-0-1/4" - P11 moved (y)
35'-0"→ 34'-4-1/4" - P12 moved (y)
35'-0"→ 34'-4-1/4" - + 7 more changes
- New 3 warnings · base-access (P1, P4, P11)
- r26+5 days
Corner posts moved for base nailing.
- Pieces
- 72
- Tasks
- 36 (−6)
- Errors
- 0 (−7)
- Warnings
- 1 (−2)
Changed from r25
- P6 base
ABA66Z→ ABU66Z - P1 moved (x)
0'-2-3/4"→ 0'-6-1/4" - P4 moved (x)
27'-0-1/4"→ 26'-8-3/4" - BACK spans
8'-11-3/4" · 8'-11-3/4" · 8'-10"→ 8'-8-1/4" · 8'-11-3/4" · 8'-6-1/2"
- Cleared 1 error · hw-capacity (P6)
- Cleared 6 errors · ply-screw
- Cleared 2 warnings · base-access (P1, P4)
- r27same day
P11 off the south rail.
- Pieces
- 72
- Tasks
- 36
- Errors
- 0
- Warnings
- 0 (−1)
Changed from r26
- P11 moved (y)
34'-4-1/4"→ 34'-0-3/4" - WALL-TRACK spans
8'-6-3/4" · 8'-4" · 7'-8-1/4"→ 8'-6-3/4" · 8'-4" · 7'-4-3/4"
- Cleared 1 warning · base-access (P11)
- r28same day
The stair.
- Pieces
- 85 (+13)
- Tasks
- 38 (+2)
- Errors
- 0
- Warnings
- 1 (+1)
Changed from r27
- STAIR added14 risers on 3 2x12 stringers
- New 1 warning · stair (STAIR)
G-003 · DIY or pro
One model for the owner-builder and the small crew.
Whether you are building your own shed or pricing a deck for a client, the plan, the checks and the lists all come from one description of the frame.
Owner-builders
Sheds · decks · lofts
Take a list you trust to the lumber yard.
Describe the frame once. 2by draws the plan, checks the spans, and writes the cut list and the shopping list from that same description, so a change to one joist changes every list.
- Cut list by stock length, with the waste on each size
- Shopping list grouped the way the yard quotes it
- Span checks that flag a member before you buy it
| Size | Stock | Sticks | Waste |
|---|---|---|---|
| 2×6Floor Frame | 10'-0" / 12'-0" | 7 | 4% |
| 4×4Floor Frame | 8'-0" | 1 | 0% |
| 2×4Walls and Roof | 8'-0" / 10'-0" | 42 | 16% |
| 2×6Walls and Roof | 8'-0" / 12'-0" | 9 | 10% |
| Total | 8 lines on the lumber order | 59 |
It computes and flags. Where your permit needs an engineer, an engineer still signs it.
Small contractors
Small wood-framed jobs
Quick takeoffs and shop drawings for small wood-framed jobs.
Price from the order list, print the set, and hand the crew sheets in the language they read. When the client moves a post, the next revision goes out with every sheet redrawn.
- Print sets: 14 sheet types for the shop loft, S-0 to S-9
- Revision and date in every title block: the shop loft is at r28
- Spanish-language sheets for the crew, from the tool’s own label table
Sheet language
SHEET S-1
Framing Plan
REV r28
2026-09-11
LL 50 + DL 10 PSF
2026-09-11
LL 50 + DL 10 PSF
DERIVED FROM STRUCTURE.YAML · 1 SQUARE = 1'-0" · 24 PX/FT · DO NOT SCALE FROM PRINT · ALL DIMENSIONS CENTRE-TO-CENTRE
G-004 · Model gallery
Start from a real model
Each of these is a working model in the demo, with its own plans, span checks, cut list and printed set. Open one, change a member, and every schedule follows.
Freestanding Timber Loft
27'-2" × 34'-7" overall
- Posts
- 13
- Sticks
- 85
- Sheets
- 33
38 joists, 2×10 at 16" on centre
No errors, 1 warning to confirm
Garden Shed 8x6
8'-1-3/4" × 6'-1-3/4" overall
- Posts
- 12
- Sticks
- 59
- Sheets
- 19
7 joists, 2×6 at 16" on centre
No errors, 3 warnings to confirm
Three-Tier Back Deck
32'-2-3/4" × 24'-2-3/4" overall
- Posts
- 18
- Sticks
- 96
- Sheets
- 33
41 joists, 2×10 at 16" on centre
In review · 6 errors open, 22 warnings
Rev r3 has open findings: a worked example of what the checks catch.
The demo opens on the last model you used. Switch models with the MODEL ▾ menu beside the project title.
G-005 · Early access
Try it on your next build.
Still being built. Try the demo today; get early access when accounts open.
No account needed. The demo runs in your browser.
- Project
- 2by
- Status
- Still being built
- Demo
- Open now
- Accounts
- Opening soon
- Demo models
- Shop Loft · Tiered Deck · Garden Shed