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Structural Engineering Software & Resource Directory

The reference library for residential and light-frame wood structural engineering: the NDS, NDS Supplement, SDPWS, ASCE 7-22 and the IBC/IRC span chapters with free-access links; TJI specifier's guides and evaluation reports; Simpson Strong-Tie catalogs; wood design software compared side by side (StructSuite, US WoodWorks, ENERCALC, ASDIP, StruCalc, RISA, SkyCiv, ForteWEB and more) on what it designs, which ASCE 7 loads it generates, the code editions it states and what it costs; plus free span calculators and learning channels. Prices and capabilities re-checked against each vendor's own site, September 2026.

31 min read Updated October 17, 2026 Written and checked by StructSuite's licensed Professional Engineer (P.E.).
On this page

A working engineer keeps a toolbox of trusted websites — the authority to download a standard, the manufacturer app to size an engineered joist, the analysis package that returns member forces, the tool that pins down wind and seismic loads. This page gathers those links in one place, organized by what each one is for, with side-by-side comparison tables in the key sections so you can pick the right tool quickly.

Most-used documents — quick access

This is a living directory — we keep adding to it over time, with more links and, where they help, screenshots. If a tool you rely on isn't here yet, it likely will be soon.

A quick mental map first, because these tools do different jobs and newcomers often mix them up:

  • Code & load authorities give you the rules and the demands — the standards (NDS, ASCE 7, AISC 360, ACI 318) and the loads acting on your structure.
  • Analysis software gives you the forces — it models the structure and returns moments, shears, and reactions.
  • Design software takes those forces and checks or sizes a member against a code.
  • Manufacturer (EWP) tools size a specific proprietary product — an LVL, an I-joist — using design values you won't find in the NDS.

Plenty of packages blur these lines, and that's fine. Use the grouping as a starting point, not a rulebook.

Choosing software for a wood-framed residential project? Jump straight to the decision checklist at the end of this page — six practical questions that narrow the field fast.


Codes, standards & design loads

Start here: the bodies that write the standards, the platforms that let you read the adopted codes, and the tools that quantify the loads you design against.

Standard-developing organizations (SDOs)

The bodies that author the design standards you cite. Their sites host the current editions, errata, and free technical resources.

American Wood Council (AWC)Wood The body that writes the U.S. wood-design standards: the NDS (its equations and adjustment factors, in ASD and LRFD), the NDS Supplement (the species design-value and section-property tables), SDPWS for shear walls and diaphragms, and the prescriptive WFCM. The current editions plus free errata, commentary, and technical reports all live here. awc.org ↗

American Institute of Steel Construction (AISC)Steel The authority behind U.S. structural-steel design: AISC 360 (the Specification for Structural Steel Buildings), the Seismic Provisions (AISC 341), and the Steel Construction Manual. The shapes database, design guides, and the standards themselves are downloadable, many free to members. aisc.org ↗

AISC Shapes Database v16.0Design data A free Microsoft Excel table of section dimensions and properties consistent with the AISC Steel Construction Manual, 16th Edition — including the 222 new shapes added in that edition. Replaces v15.0; U.S. customary and metric units are both included. aisc.org ↗

American Concrete Institute (ACI)Concrete The authority behind U.S. concrete design: ACI 318 (Building Code Requirements for Structural Concrete) plus the wider family of codes and specs for detailing, durability, repair, and materials. The site carries the current code with commentary and a deep library of technical documents. concrete.org ↗

American Society of Civil Engineers (ASCE)Loads The society behind ASCE/SEI 7 — the minimum-design-loads and load-combinations standard nearly every U.S. building code adopts by reference — along with ASCE 41 for seismic evaluation and retrofit, manuals of practice, journals, and the free hazard lookup tools that quantify site loads. asce.org ↗

APA – The Engineered Wood AssociationReference The trade association and testing authority for engineered wood — glulam, I-joists, plywood, OSB, and SCL. Publishes product reports, span and capacity tables, environmental data, and clear technical notes on stress classes, layups, and panel grades, and is the source behind many proprietary wood-product values. apawood.org ↗

Straight to the standards

The design standards those bodies publish — the documents the code adopts by reference and a member check ultimately cites.

NDS — National Design Specification for WoodAWC standard AWC's base standard for wood design — the reference design values, adjustment factors, and connection provisions behind every solid-sawn and engineered wood member check. awc.org ↗

NDS Supplement (2024) — Design Values for WoodAWC standard The companion volume to the NDS — the reference design value tables (Fb, Fv, E, Fc…) for sawn lumber and glulam by species, grade and size that every allowable-stress wood check reads from. awc.org ↗

SDPWS — Special Design Provisions for Wind & SeismicAWC standard AWC's lateral standard for wood — shear-wall and diaphragm unit capacities, aspect-ratio limits, and the force-transfer rules behind wood lateral-force-resisting systems. awc.org ↗

WFCM — Wood Frame Construction ManualAWC standard AWC's prescriptive and engineered tables for conventional light-frame construction — spans, connections, and uplift/lateral details organized by wind speed and seismic category. awc.org ↗

ASCE/SEI 7-22 — Minimum Design LoadsLoads standard The current (2022) edition of the standard that defines dead, live, wind, seismic, snow, rain, ice, flood and tsunami loads and the load combinations nearly every U.S. building code adopts by reference — the starting point for almost any demand on a structure. asce.org ↗

ANSI/AISC 360-22 — Specification for Structural Steel BuildingsSteel standard AISC's base standard for steel design — the member, connection and stability provisions (ASD and LRFD) behind every structural-steel check. Free to read on the AISC current-standards page. aisc.org ↗

ANSI/AISC 341-22 — Seismic Provisions for Structural Steel BuildingsSteel standard AISC's seismic standard — the detailing and capacity-design rules for moment frames, braced frames and shear walls in higher seismic categories. Free to read on the AISC current-standards page. aisc.org ↗

ANSI/AISC 358-22 — Prequalified Connections for Steel Moment FramesSteel standard The prequalified connections standard, developed by the AISC Connection Prequalification Review Panel per Chapter K of the Seismic Provisions — 11 moment connections (RBS, bolted end-plates, BFP, WUF-W and more) prequalified for use in special and intermediate steel moment frames without additional testing. aisc.org ↗

ACI 318 & codes/specsConcrete standards ACI 318 (Building Code Requirements for Structural Concrete) and the wider ACI family of codes and specifications for detailing, durability, repair and materials. concrete.org ↗

Reading the adopted code itself

The building code that governs a project (IBC, IRC, and their referenced standards) is read online through one of these two platforms.

PlatformCoverageFree to read?Strength
ICC Digital CodesI-Codes + many state/standard adoptionsYes (premium adds tools/markup)Official ICC text; precise section links
UpCodesIBC/IRC + state amendments + referenced standardsYes (paid adds search AI/collaboration)Fast search & cross-referencing across adopted codes

Design loads

Once you know the code, you need the numbers it asks for.

Prescriptive span chapters

The specific code chapters that carry conventional light-frame span tables (the source behind prescriptive joist/rafter sizing).

Free web calculators

Free browser tools from AWC and APA that apply the NDS and AWC SDPWS directly — handy for a quick check or to confirm a prescriptive choice.

Design aids

Free published aids that do the arithmetic for you — closed-form statics to check an analysis against, and the section properties of every standard lumber size.


Engineered wood products (EWP)

When you specify a proprietary product — an LVL header, a manufactured I-joist — its design values come from the manufacturer's evaluation report, not the NDS. This section has both the apps that size those products and the published documents behind their numbers.

Sizing tools

Free cloud apps that pick a product and check it against your loads.

ToolProductsPlatformCost
ForteWEBWeyerhaeuser Trus Joist (TJI, Microllam, Parallam, TimberStrand) + sawn/glulamBrowserFree
BC CalcBoise Cascade (BCI, VersaLam, …)Browser/desktopFree

Each manufacturer app is tuned to its own products and ESR values — handy when the product is already chosen, but tied to that brand. A code-based design tool (below) — StructSuite, for instance — instead works from the NDS and the manufacturer ESR values directly, so several brands of LVL/LSL/PSL (Microllam, Versa-Lam, TimberStrand, Parallam) sit side by side in one check.

Evaluation reports

Where each manufacturer's code-recognized design values for engineered wood actually live.

No need to search the directory for the common residential lines — these are the current reports, each linked straight to the PDF:

ProductBrandManufacturerReport
I-joistTJIWeyerhaeuserESR-1153
I-joistBCIBoise CascadeESR-1336
I-joistLP SolidStart · PWTLouisiana-Pacific / Pacific WoodtechESR-1305
LVLMicrollamWeyerhaeuserESR-1387
LVLVersa-LamBoise CascadeESR-1040
LVLRigidLam (reference only — not selectable in StructSuite)RoseburgESR-1210
LVLPWT LVL (reference only — not selectable in StructSuite)Pacific WoodtechESR-2909
LSLTimberStrandWeyerhaeuserESR-1387
PSLParallamWeyerhaeuserESR-1387

Before you cite one, confirm the report is still live on ICC-ES — brands get sold and reports get quietly withdrawn. The TJI, BCI, LP/PWT, Microllam, Versa-Lam, TimberStrand and Parallam values inside StructSuite come straight from these reports.

Trus Joist product literature

The specifier's guide and technical bulletins that carry the design values, span tables, and details you cite when you specify a TJI joist.


Structural analysis & design software

The packages firms run day to day. Some are pure analysis (you take the forces elsewhere to design), some are component-design libraries, several do both, and a few are wood-specialized. The table after the cards lays them side by side.

StructSuiteBrowser · wood + loads Browser-based design for wood beams, columns, shear walls, joists, rafters, footings and cantilever retaining walls (NDS 2024, AWC SDPWS 2021, ASCE 7-22, IBC 2024, ACI 318-25), plus steel beams and columns to AISC 360-22 and ASCE 7-22 load generation — dead, live, wind and seismic (dead from material/assembly weights, live by occupancy; snow is not generated). Each check is shown step-by-step with its code reference — the formulas, the substituted values and the governing code tables inline — recalculating live as you change an input. A book icon beside a field opens the governing provision quoted verbatim from the standard — 80 sections across IBC 2024, ASCE 7-22, NDS 2024, SDPWS 2021, ACI 318-25 and AISC 360-22 — so choosing a table row or entering a value doesn't mean opening the book, and inputs are checked against the code's own limits as you type rather than at the end. Free to use in full; A free account keeps one project in the cloud; Pro adds PDF export, unlimited cloud save and a view-only verification link for the plan checker. structsuite.com ↗

US WoodWorks SizerWood design The long-established desktop standard for U.S. wood member design — beams, columns, studs, joists and rafters — to the NDS and ASCE 7, with span checks, load patterning, and a clear printed calc. Sold alongside companion Shearwalls and Connections modules (below). webstore.cwc.ca ↗

US WoodWorks ShearwallsWood lateral WoodWorks' desktop tool for wood shear-wall design — distributing wind and seismic story forces to the wall lines and checking each segmented or perforated shear wall to the IBC and AWC SDPWS, including hold-down and chord forces. webstore.cwc.ca ↗

SPEC ToolboxBrowser · timber Browser-based timber design — CLT, glulam, and dowel/screw/bolt connections, light-frame and fire — to the NDS, Eurocode 5, CSA O86 and AS 1720, with transparent calcs and PDF reports. spectoolbox.com ↗

ENERCALCDesign library The Structural Engineering Library — a long-trusted, deep set of quick, code-checked component calculations spanning wood, steel, concrete and masonry members, footings, retaining walls and connections. Runs on the desktop or its cloud edition and produces detailed printed calcs. enercalc.com ↗

ASDIP StructuralDesign library Focused, affordable design modules for steel, concrete, wood, masonry and retaining walls — base plates, anchor bolts, footings, beams and columns. Handy standalone checks with clear, code-referenced output for everyday components. asdipsoft.com ↗

StruCalcWood design Wood-focused desktop sizing for beams, columns, joists, rafters and headers to the NDS — long popular in residential and light-frame practice for fast member checks with a clean printed calc. strucalc.com ↗

SkyCivCloud Browser-based structural analysis and design — 3D frame and FEA modeling plus member-design checks for steel, wood, concrete and cold-formed across many international codes. Runs entirely in the cloud, with an API and nothing to install. skyciv.com ↗

RISAAnalysis + design A long-established desktop suite — RISA-3D, RISAFloor and RISAConnection — for analysis and code design across materials, including wood members, walls and connections. Strong for whole-structure modeling that hands forces straight into the member checks. risa.com ↗

CSI — ETABS / SAP2000 / SAFEAnalysis ETABS, SAP2000 and SAFE — an industry standard for general finite-element analysis of buildings, bridges and slabs. You typically extract member forces, drifts and reactions here, then carry them into a design tool for the code member check. csiamerica.com ↗

Calcs.comBrowser · multi-code A cloud platform with 240+ standards-aligned calculators (IBC, AISC, ACI, NDS, Eurocode and more). Keeps inputs, formulas and code references together, with load-linking and a documented calc/audit trail. calcs.com ↗

CalcBookSoftware Structural calculation software for everyday member and component design, organizing routine checks into a reusable, well-documented calc set. calcbook.com ↗

How they line up. The cards above say what each tool is for; these three tables compare them on what actually decides the job — what it designs, the loads it builds for you, and how you run it and what it costs. (Tools are listed alphabetically. Split in three so nothing gets squeezed on a narrow screen. ForteWEB is carried in from the engineered-wood section above, since you'd weigh it alongside these.)

How to read the check marks. A ✓ means the vendor's own published material states the capability. A dash means they don't claim it — which is not proof the feature is missing, only that we won't assert it on their behalf. Several vendors publish no code editions or prices at all, and those cells say so.

What each tool designs.

ToolWood membersWood shear wallsSteelConcrete & foundations
ASDIP✓✓✓✓
Calcs.com✓—✓✓
CSI (ETABS/SAP2000/SAFE)——✓✓
ENERCALC✓✓✓✓
ForteWEB✓———
RISA✓—✓✓
SkyCiv✓—✓✓
SPEC Toolbox✓———
StruCalc✓✓✓✓
StructSuite✓✓✓✓
US WoodWorks✓✓——

The loads it builds for you (per ASCE 7). A check mark means the tool generates that load type for you, rather than expecting you to arrive with it.

ToolDeadLiveWindSnowSeismic
ASDIP——✓✓✓
Calcs.com—————
CSI (ETABS/SAP2000/SAFE)—————
ENERCALC——✓✓✓
ForteWEB—————
RISA—————
SkyCiv——✓✓✓
SPEC Toolbox—————
StruCalc——✓✓✓
StructSuite✓✓✓—✓
US WoodWorks——✓—✓

StructSuite is the only tool here that assembles dead and live loads from the ASCE 7-22 tables, and the only one of the load-generating tools that does not do snow — where snow governs the roof, that stays a separate calculation.

How you run it, and what it costs.

ToolPlatformCode editions statedWhat it costs
ASDIPCloud subscription (2 seats)"Latest US & Canada" — editions not published$395/yr per module · $1,595/yr suite · 15-day trial
Calcs.comBrowserIBC, AISC, ACI, NDS, Eurocode — years not published14-day trial, no card · plan prices not published
CSI (ETABS/SAP2000/SAFE)Desktop, cloud sign-in licensingNot publishedNot published — quote
ENERCALCDesktop + cloud editionIBC 2024 · ASCE 7-22 · ACI 318-25$1,699/yr (2 users) or $199/mo · 30-day full trial
ForteWEBBrowserIBC 2024 · ASCE 7-22 · NDS 2024Free
RISADesktop (RISACalc is browser-based)Not publishedNot published — quote · 10-day trial
SkyCivBrowserAISC, ACI, AS, Eurocode, CSA — years not publishedFree tools · paid plans, prices not published
SPEC ToolboxBrowserNDS, Eurocode 5, AS1720.1, CSA O86 — years not publishedFree tier, no time limit · Pro US$1,000/yr
StruCalcDesktopASCE 7-22 · NDS 2024 · IBC 2024 · ACI 318-19 · AISC 360-16$99.97/mo · 30-day trial
StructSuiteBrowserASCE 7-22 · NDS 2024 · SDPWS 2021 · IBC 2024 · ACI 318-25 · AISC 360-22Free to use in full · Pro $100/mo or $1,000/yr · $50 one-week pass
US WoodWorksDesktopNDS 2024 · IBC 2024 · ASCE 7-22 · SDPWS 2021$210/yr

Every row above was re-checked against the vendor's own website on 20 September 2026. Prices and code editions change, and some vendors publish neither — confirm both before you buy. If something here is wrong about your software, tell us and we'll correct it.


Connectors, trusses & framing hardware

Wood structures live and die by their connections and framing systems. These tools cover the hardware and the prefabricated components.

Simpson Strong-Tie product literature

The catalogs and bulletins that carry the allowable loads, installation requirements, and code listings you cite when you specify a connector or lateral system.


Books & references

The textbooks that sit on the desk next to the code — the ones that explain why a provision reads the way it does and walk a design from loads to connection. A short, curated shelf we'll keep adding to.


Learning & social channels

Featured — creators covering StructSuite

▶ Featured video: A complete structural calculation package built start to finish, in 32 minutes — every featured channel sits here at the top of the section, with a direct link to its StructSuite video.

YouTube On YouTube. Channels worth following — practical structural and civil engineering explained on video. A good way to build intuition, see worked examples, and pick up code know-how between projects.

Instagram On Instagram. Accounts worth following for quick visual inspiration — real-world structures, framing and detailing from the field, a useful reality check against the drawings.

For creators. Cover StructSuite on your channel — a review, a walkthrough, a design-along — and get featured here, at the top of this section with a link to your video. Details in our creators & affiliate program.


Choosing a tool for light-frame & residential wood

Most of the work on a wood-framed building isn't whole-structure finite-element analysis — it's a stack of member, shear-wall, connection and footing checks, plus the wind and seismic loads that drive them. A few practical questions narrow the field:

  • Do you need the loads too, or just the member check? Most tools expect you to arrive with the loads already worked out — RISA, CSI and the component libraries assume that. ASDIP, ENERCALC, SkyCiv and StruCalc generate wind, snow and seismic for you. StructSuite is the only one here that also assembles dead and live loads from the ASCE 7-22 tables (material and assembly weights, occupancy live loads) — and the only load-generating tool that doesn't do snow, so in snow country that stays a separate calculation.
  • Which code edition does it work to? This is the question that bites at plan check, because your jurisdiction has adopted a specific edition. ForteWEB, US WoodWorks and StructSuite all state NDS 2024, IBC 2024 and ASCE 7-22; ENERCALC states IBC 2024, ASCE 7-22 and ACI 318-25; StruCalc states ASCE 7-22 and NDS 2024 but ACI 318-19 and AISC 360-16. Several vendors don't publish editions at all — ask before you buy, and ask again at renewal.
  • Desktop or browser? Desktop suites (US WoodWorks, StruCalc, RISA, CSI) are mature and run offline. Browser tools (ForteWEB, SkyCiv, SPEC Toolbox, Calcs.com, StructSuite) install nothing and open from any machine. ENERCALC and ASDIP run both ways.
  • What does it cost to get started? Two are genuinely free to use: ForteWEB, for Weyerhaeuser products, and SPEC Toolbox's free tier, which has no time limit. StructSuite is free to use in full — every module, every calculation on screen — with Pro needed to export, save to the cloud or share a verification link. The rest are trials: ENERCALC and StruCalc 30 days, ASDIP 15, Calcs.com 14, RISA 10. On price, US WoodWorks at $210/yr is much the cheapest way into dedicated wood design; ENERCALC at $1,699/yr is the broadest library.
  • How does the reviewer see your work? Some workflows still mean printing a thick calc package. Calcs.com keeps inputs, formulas and code references together with a documented audit trail; StructSuite produces a view-only link to the step-by-step calculations, so a plan-check engineer can follow each substitution and code reference online instead of in a PDF.
  • Do you want the code text where you're working, or on your desk? Most tools cite the section they applied — you still open the standard to see what it says. Calcs.com keeps code references alongside the inputs and formulas; CalcBook organizes routine checks into a documented calc set. StructSuite goes to the provision itself: a book icon beside a field opens the governing section quoted verbatim (80 sections across IBC 2024, ASCE 7-22, NDS 2024, SDPWS 2021, ACI 318-25 and AISC 360-22), so picking a row out of a table or entering a value doesn't mean reaching for the book — and where the code sets a limit on an input, the field flags it as you type instead of after you run the check. Worth weighing if an EIT is doing the work, or if you want the reviewer to see the basis rather than take it on trust.
  • Who assembles the package? A submittal needs a cover sheet and a table of contents tying it together, which is often manual desktop-publishing work. StructSuite generates both from the modules you've completed, so the package comes out paginated and consistent; with the desktop suites you'll typically collate the printed output yourself.

The directory above lists the options for each of these so you can match the tool to the job.


Frequently Asked Questions

Quick answers to the questions that bring engineers to this page — each one links to the resource that carries the full detail.

Where can I read the IBC and IRC for free?

On two platforms: ICC Digital Codes — the ICC's own library of the I-Codes, free to read in the browser with section-level links — and UpCodes, a fast searchable view of adopted codes and state amendments, also free to read. Paid tiers on both add search and collaboration tools, but reading the code text costs nothing.

What is the difference between the NDS and the NDS Supplement?

The NDS is the standard itself — the equations, adjustment factors, and connection provisions for wood design in ASD and LRFD. The NDS Supplement is its companion volume of design-value tables — the reference values (Fb, Fv, E, Fc and the rest) for sawn lumber and glulam by species, grade and size. A wood member check reads from both: the Supplement supplies the base values, and the NDS tells you how to adjust and apply them.

Where do I find span tables for TJI joists?

In Weyerhaeuser's own literature: the TJ-4000 Specifier's Guide carries the floor and roof span tables, design values and web-hole charts for TJI 110–560D joists; TB-805 covers TJI ceiling joists supporting attic load, and TB-824 adds roof thrust load. All three are free downloads from the Weyerhaeuser document library.

Is ASCE 7-22 free to read?

The standard itself is a paid publication from ASCE. What is free is the official ASCE 7 Hazard Tool, which returns the ASCE 7 site parameters for any U.S. location — basic wind speed, seismic Ss and S1, ground snow and more — the numbers a load calculation actually starts from.

What software can design wood shear walls?

Several tools in this directory. StructSuite designs wood shear walls per AWC SDPWS as a guided, step-by-step wizard in the browser — including the wind and seismic loads that drive them. You pick the sheathing straight from a replica of SDPWS Table 4.3A exactly as it reads in the standard, select the hold-down, and the anchor bolt row follows the hold-down's anchor diameter (with a transition coupler where SABR has no matching size), design the end posts per the NDS, and can include the collector (drag strut) force check per ASCE 7-22. US WoodWorks Shearwalls is the long-established desktop tool for distributing story forces to wall lines; and APA's free FTAO Calculator handles wood shear walls with openings by the force-transfer-around-openings method.

Which structural design software calculates ASCE 7 loads for you?

Most don't — general analysis tools and most component libraries expect you to arrive with the loads already worked out. Of the tools in this directory, ASDIP, ENERCALC, SkyCiv and StruCalc generate wind, snow and seismic loads; US WoodWorks generates wind and seismic. StructSuite is the only one that also assembles dead and live loads from the ASCE 7-22 tables — material and assembly weights per Table C3.1-1a, occupancy live loads per Table 4.3-1 — though it does not generate snow. See the loads table above for the full comparison.

How much does wood design software cost?

From nothing to about $1,700 a year, checked against each vendor's own site in September 2026. ForteWEB is free for Weyerhaeuser products and SPEC Toolbox has a free tier with no time limit. US WoodWorks is $210/yr. StruCalc is $99.97/mo, ASDIP $395/yr per module or $1,595/yr for the suite, and ENERCALC $1,699/yr for two users or $199/mo. StructSuite is free to use in full — every module, every calculation on screen — with Pro at $100/mo or $1,000/yr for PDF export, cloud save and verification links. RISA and CSI don't publish prices.

Where do allowable loads for joist hangers and hold-downs come from?

From the manufacturer's literature and code reports: Simpson's Wood Construction Connectors catalog carries the allowable loads, fastener schedules and code-report references for its hangers, straps and hold-downs; MiTek's Product Selector does the same for its hardware; and the code-recognized basis for each product lives in its evaluation report on ICC-ES.


StructSuite publishes this directory, and it's listed among the tools it competes with on the same terms. We've described every entry — ours included — by what it actually does; if we've got a detail wrong, tell us and we'll fix it.