HOME SERVICES ABOUT BLOG SERVICE AREAS VENDORS CAREERS CONTACT
Free OSP Engineering Tool
Updated July 2026

Pole Loading Calculator (NESC Screening Pre-Check)

Will this pole likely pass, or should you budget make-ready? Screening-level groundline moment check for a tangent wood distribution pole with communication attachments — NESC Rule 250B district ice and wind, Grade B/C load and strength factors, and ANSI O5.1 pole dimensions. Free, instant, shareable per pole. Built by the OSP engineering team that performs full pole loading analysis at $45–$75 per pole.

Screening estimate — not a pole loading analysis. This tool performs a simplified NESC Rule 250B transverse-wind check on a tangent wood pole using published ANSI O5.1 dimensions and typical assumptions. It does not model wire tensions, line angles, guying, equipment, vertical loads, pole decay, or Rules 250C/250D extreme loads, and it is not a substitute for a full pole loading analysis performed and sealed by a qualified engineer. Pole owners and joint-use agreements require a full PLA (O-Calc® Pro or SPIDAcalc) before attachment. Draftech International assumes no liability for attachment or construction decisions based on this screening output. Order a full PLA — typically $45–$75 per pole with stamped deliverables.

Pole & Loading Inputs

Rule 250B districts run roughly north → south: Heavy = northern states/high elevations, Medium = middle band, Light = Gulf Coast, FL & desert SW. See the district map in the NESC or RUS 1724E-150.
Railroad, limited-access highway & navigable-water crossings and other higher-risk locations are Grade B.
Poles > 60 ft above grade trigger NESC 250C/250D extreme-load cases — out of scope here.
ft
Auto = 10% of length + 2 ft (industry rule of thumb). Edit if the pole is set deeper/shallower.
in
Auto from ANSI O5.1 minimums (interpolated at groundline). A field-measured value overrides — tape the pole at groundline.
ft
(Adjacent span 1 + adjacent span 2) ÷ 2 — the length of cable this pole carries wind for.
Height = attachment height above ground (AGL). OD = effective bundle diameter, inches — for overlashed cables enter the combined bundle OD. Presets: power neutral 0.5", CATV coax + strand 0.8", telco/fiber lashed bundle 1.2".
Proposed New Attachment (what changes)

Screening Result

Screening result only — attachment permits require a full pole loading analysis.
Factored demand
Factored capacity
Utilization
Pole above ground

Groundline moment breakdown (unfactored)

ComponentHt ftMoment ft·lbShare

Demand vs capacity

Need a stamped PLA? $45–$75 per pole — full analysis in O-Calc® Pro or SPIDAcalc with stamped deliverables, ready for the pole owner's permit application. Screening a whole route? Send us your pole list and we'll quote the run.

Order a Full PLA →

Cite or link this tool

Pole Loading Pre-Check Calculator, Draftech International, https://draftech.com/tools/pole-loading-calculator (accessed 2026-07-10)

What This Pole Loading Calculator Checks

This is a screening-level pre-check for the question every make-ready coordinator and OSP designer asks before an attachment application: is this pole likely to pass, or should we budget make-ready now? The tool computes the factored transverse wind moment at the groundline — cables loaded with NESC Rule 250B district ice and wind, plus wind on the tapered pole itself — and compares it against the pole's factored bending capacity from its ANSI O5.1 class, species fiber stress, and groundline circumference. Transverse wind typically governs communication attachments on tangent distribution poles, which is why a moment-only screen is a useful first filter.

Every input is editable and the result recalculates instantly. The share link serializes the whole pole — ID, district, grade, class, spans, every attachment — so you can paste a filled-in screening into an NJUNS note, a make-ready ticket, or an email and the recipient sees exactly what you see. The print view produces a one-page submittal-style screening worksheet.

What This Tool Does NOT Model

Rule of thumb for the verdict bands: under 70% utilization the pole is unlikely to be the constraint on your application; 70–100% means expect the pole owner's engineering review to require analysis and possibly make-ready; over 100% means budget for make-ready or pole replacement before you submit. All three verdicts still require a full PLA for the permit — see our pole loading & make-ready hub for how the screening, analysis, and construction phases fit together.

Method & Constants (NESC 250B / ANSI O5.1 / RUS 1724E-150)

The tool applies the district loads of NESC Rule 250B, the Table 253-1 transverse-wind load factors, and the Table 261-1A strength factors for wood structures, with pole dimensions from ANSI O5.1 and the groundline-moment formulation used in USDA RUS Bulletin 1724E-150:

NESC District (250B)Radial IceWind Pressure
Heavy0.50 in4 psf
Medium0.25 in4 psf
Light0 in9 psf
FactorGrade BGrade C
Load factor, transverse wind (NESC Table 253-1)2.502.20
Strength factor, wood structures (NESC Table 261-1A)0.650.85
Species (ANSI O5.1)Designated Fiber Stress Fb
Southern Yellow Pine8,000 psi
Douglas Fir8,000 psi
Western Red Cedar6,000 psi
P = district wind (psf)      t = radial ice (in)      H = pole length − setting depth (ft)
D_gl = C_gl/π   D_top = C_top/π   (diameters, in)

Cable wind moment:   M_i    = P · ((OD_i + 2t)/12) · WindSpan · h_i          [ft·lb]
Pole wind moment:    M_pole = P · H² · (D_gl + 2·D_top) / 72                 [ft·lb]
Factored demand:     M_load = LF · (Σ M_i + M_pole)        LF = 2.50 (B) / 2.20 (C)
Section modulus:     S      = C_gl³ / (32·π²)                               [in³]
Factored capacity:   M_cap  = SF · F_b · S / 12            SF = 0.65 (B) / 0.85 (C)
Utilization:         U      = M_load / M_cap × 100%

Pole top and groundline circumferences are the ANSI O5.1 minimums (classes 1–6, lengths 30–55 ft), with the groundline value interpolated between the tabulated 6-ft-from-butt circumference and the top at the actual setting depth. Public summaries of the constants: USDA RUS Bulletin 1724E-150 and the IAEI strength-and-loading overview of NESC Section 25. Where a measured groundline circumference is available, enter it — measured beats tabulated. Combinations not manufactured under ANSI O5.1 (e.g., Class 6 × 50 ft) are disabled in the selectors.

Tool logic by the Draftech pole loading engineering team — reviewed by Julio Martinez, Partner (17 years OSP engineering). Questions or a constant you'd challenge? info@draftech.com.

From Screening to Permit: Where This Fits

The workflow that actually gets fiber on poles: screen the route (this tool) → order the full pole loading analysis on every pole in the application ($45–$75 per pole, stamped) → resolve failures through make-ready engineering → submit to the pole owner. Our pole loading & make-ready services hub walks the whole sequence, and the background reading lives on the blog: what a pole loading analysis is, NESC pole loading compliance for fiber attachments, O-Calc Pro vs SPIDAcalc, and what make-ready costs per pole.

Common Questions

Pole Loading — FAQ

What is a pole loading analysis?

+

A pole loading analysis (PLA) is a structural evaluation of a utility pole against every load it carries — conductors, communication cables, equipment, guying, and the NESC Rule 250 weather cases — verified against the pole's strength for its grade of construction. Pole owners require a passing PLA before approving new attachments because an overloaded pole is a safety and liability problem for everyone on it. A full PLA models wire tensions, line angles, vertical loads, and existing pole condition in software such as O-Calc Pro or SPIDAcalc, and is reviewed and sealed by a qualified engineer. Draftech performs full PLAs at $45–$75 per pole with stamped deliverables. This free tool is only the screening step in front of that analysis.

What are the NESC loading districts (Heavy, Medium, Light)?

+

NESC Rule 250B divides the United States into three loading districts that set the simultaneous ice and wind a structure must be designed for: Heavy district — 0.5 in of radial ice plus 4 psf wind; Medium district — 0.25 in of radial ice plus 4 psf wind; Light district — no ice and 9 psf wind. The districts run roughly north to south: Heavy covers the northern states and higher elevations, Medium the middle band, and Light the Gulf Coast, Florida, and the desert Southwest. The district map is published in the NESC and summarized in USDA RUS Bulletin 1724E-150. Note that Rules 250C and 250D add extreme wind and extreme ice cases for structures over 60 ft above grade, which this screening tool does not model.

When do you need a stamped pole loading analysis?

+

Practically speaking: before every new attachment. Pole owners and joint-use agreements require a full pole loading analysis as part of the attachment permit for each pole in the application, and many owners specify the software (O-Calc Pro or SPIDAcalc) and require engineering review. A screening tool can tell you which poles in a route are likely to pass and which will need make-ready budget, but it cannot be submitted with a permit application. You always need the full, sealed analysis for corner and deadend poles, guyed poles, poles carrying equipment, poles in poor condition, and any pole this screen rates marginal or over capacity. Draftech delivers stamped PLAs at $45–$75 per pole.

What triggers make-ready on a pole?

+

Make-ready is triggered when the pole, as it stands, cannot legally or structurally accept the new attachment. The common triggers are: the pole loading analysis shows utilization over 100% with the new cable (structural make-ready — pole replacement or guying); NESC clearance violations — insufficient separation from power (Rule 235) or insufficient ground clearance at mid-span (Rule 232) — which force existing attachers to rearrange (rearrangement make-ready); and communication space that is simply full, requiring existing cables to be moved to create an open position. Overlashing to an existing strand can avoid some make-ready but still adds load that must be checked. Screening utilization above roughly 70% on this tool is a signal to budget for make-ready engineering before the permit round.

Why isn't this screening tool a substitute for a full PLA?

+

This tool checks one governing effect — factored transverse wind moment at the groundline on a tangent wood pole — using published ANSI O5.1 dimensions and NESC Rule 250B district loads. A full pole loading analysis also models wire tensions and line angles, deadend and guying loads, vertical loads and buckling, equipment such as transformers and risers, actual measured pole condition and decay, and the Rule 250C/250D extreme weather cases where they apply. Those effects can govern, which is why pole owners only accept a full PLA performed in O-Calc Pro or SPIDAcalc and reviewed by a qualified engineer. Use the verdict bands here as a budgeting signal: under 70% utilization the pole is unlikely to be the constraint, 70–100% expect analysis and possible make-ready, and over 100% budget for make-ready or replacement.

From Screening to Stamped

Screened the Route? Order the Full PLA.

Send us your pole list — pole IDs, route maps, or a spreadsheet export of your screening links. We'll return a full pole loading analysis on every pole, performed in O-Calc® Pro or SPIDAcalc with stamped deliverables, at $45–$75 per pole. Active in 22 states. Available across all 50 U.S. states.

Order Pole Loading Analysis

Email directly: info@draftech.com — or call 305-306-7407. We reply within one business day. | Explore the pole loading & make-ready hub →

Draftech International provides pole loading analysis, make-ready engineering, and joint-use attachment engineering across all 50 U.S. states. This free NESC screening calculator is the pre-check; the stamped deliverable is our pole loading analysis service at $45–$75 per pole. Planning a route? Start at the pole loading & make-ready hub or contact our team.