> For the complete documentation index, see [llms.txt](https://docs.paragontruss.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.paragontruss.com/design/reference/load-settings.md).
# Load Settings Reference
This page describes each setting in the **Load Settings** panel and what it affects. Load settings exist to help you apply the loads your project's building code requires; Paragon uses them to generate the set of load cases a component is analyzed for. The building code (and the engineer of record) is authoritative — these descriptions explain what each setting changes in Paragon, not which value your project requires. Where a section references a code clause, the clause is named so you can consult the source.
For how to open and edit the panel, see [Load Settings](/design/how-to/general/modify-project-and-component-settings/load-settings.md). Loads that aren't produced from these settings can be added manually; see [Creating Additional Loads](/design/how-to/general/modify-project-and-component-settings/creating-additional-loads.md).
{% hint style="info" %}
Which settings appear depends on the component type (roof vs. floor) and on the selected **Design Code**. Settings that only show in certain situations are noted below.
{% endhint %}
## Design Code
The Design Code (shown under **General**, and as the panel subtitle) pairs a **building code** with a **design standard** (TPI 1 edition). It is the master control for the whole panel: the building code determines which ASCE 7 edition the wind, snow, and tornado calculations follow, and the design standard determines which TPI 1 edition governs member checks. Several settings only appear, or change their behavior and the code clauses they cite, based on this selection:
* **Tornado** loads appear only for building codes that reference **ASCE 7-22 or later** (the 2024/2025-era IBC, IRC, CBC, CRC, FBC, FRC, BCNYS, and RCNYS codes).
* **Person loading** appears only for design codes using **TPI 1-2022 or later**.
* The **Snow** ground-snow input, **Wind** enclosure options, and the cited ASCE sections shift between ASCE 7-10, 7-16, and 7-22.
* The **One- or two-family dwelling** option appears only for residential building codes (CRC, FRC, IRC, RCNYS).
Changing the building code between a residential and non-residential code automatically adjusts the dwelling/storage-load options to remain consistent.
## Roof Top Chord Live Load
Applies to roof components.
### TC Live Load — psf
> The top-chord live load applied to the roof, in pounds per square foot.
### Consider Unbalanced
> When on, unbalanced roof live load cases are generated in addition to the balanced case.
## Roof Bottom Chord Live Load
Applies to roof components.
### BC Live Load — psf
> The bottom-chord live load applied to the roof, in pounds per square foot.
### Non-concurrent with other live loads
> When on, the bottom-chord live load is applied in its own load cases rather than simultaneously with other live loads.
### One- or two-family dwelling
> Certain bottom chord live loads are mandated by IBC/IRC/FBC for one- or two-family dwellings. Checking this box will cause them to be generated automatically. These loads are in addition to anything supplied for the bottom chord live load.
This option appears only for residential building codes. Turning it on also turns on **Use full storage load**.
### Use full storage load
> Generates concurrent bottom chord live loads if a 3' 6" tall and 2' wide space exists along the bottom chord. The loads are 20 PSF where the space fits and 10 PSF where it does not fit. If there is nowhere it fits, storage loading is omitted. These loads are in addition to anything supplied for the bottom chord live load in the field above. You can uncheck this box if adjacent trusses do not support the storage load in the same positions, as detailed in the building code. There are also code-specific exceptions for which you might uncheck this; your code may except trusses where the insulation covers the bottom chord or where there is no attic access of at least 20"x30". Check your building code for more details.
### Apply 10 PSF non-concurrently with storage load
> When unchecked, the 10 PSF load where the storage space does not fit is applied concurrently with the 20 PSF storage load, which is based on the building code. Checking this box applies them non-concurrently.
The checkbox is only editable while **Use full storage load** is on, since it changes how that setting's loads are applied.
IBC 2024 Section 1607.22.2 details the requirements for the 10 PSF live load on the portions of the bottom chord without storage clearance. Under the IBC/IRC 2009 building codes the setting has no effect, since those codes already apply the reduced load non-concurrently.
## Roof Top Chord & Bottom Chord Dead Load
Applies to roof components.
### TC Dead Load / BC Dead Load — psf
> The dead load applied to the roof top chord (or bottom chord), in pounds per square foot.
### Add self-weight of the component
> When on, half of the truss's own weight is added to this chord's dead load.
### Overhang soffit dead load — psf
> Dead load applied to the roof overhang's soffit, in pounds per square foot.
Shown with the roof dead-load settings only.
## Floor Top Chord Live Load
Applies to floor components.
### TC Live Load — psf
> The top-chord live load applied to the floor, in pounds per square foot.
### Consider Unbalanced
> When on, unbalanced floor live load cases are generated in addition to the balanced case.
### Consider Moving Office Load
> When on, a concentrated moving (rolling) office live load is generated and moved along the span to find its worst-case position.
### Moving Office Load — lbs
> The magnitude of the moving office load, in pounds. Shown only when *Consider Moving Office Load* is on.
### Moving Office Load Length — ft
> The length over which the moving office load is distributed, in feet. Shown only when *Consider Moving Office Load* is on.
## Floor Bottom Chord Live Load
Applies to floor components.
### BC Live Load — psf
> The bottom-chord live load applied to the floor, in pounds per square foot.
### Non-concurrent with other live loads
> When on, the bottom-chord live load is applied in its own load cases rather than simultaneously with other live loads.
## Floor Top Chord & Bottom Chord Dead Load
Applies to floor components.
### TC Dead Load / BC Dead Load — psf
> The dead load applied to the floor top chord (or bottom chord), in pounds per square foot.
### Add self-weight of the component
> When on, half of the truss's own weight is added to this chord's dead load.
## Snow
Applies to roof components. Snow calculations follow the ASCE 7 edition tied to the building code, so some inputs and labels below change with that edition.
{% hint style="info" %}
The automatically-generated snow loads for a truss only take into account that truss's profile and these load settings. The shape and size of the rest of the roof and the presence of other nearby buildings may need to be accounted for using manual loads.
{% endhint %}
### Ground Snow Load — psf
> The ground snow load used to derive roof snow loads, in pounds per square foot.
The radio buttons select which value drives the calculation. Under ASCE 7-22 and later, both an **Ultimate Ground Snow Load** and an **ASD Ground Snow Load (p****g(asd)****)** are offered; earlier editions show a single **Ground Snow Load (p****g****)**. You can alternatively drive the calculation from a **Flat Roof Snow Load (p****f****)** entered directly.
### Max Roof Snow Load (pf / ps) — psf
> Read-only. The resulting maximum roof snow load Paragon computed for this truss, shown for a single selected component.
The subscript reflects the roof pitch: pf for low-slope roofs and ps for sloped roofs.
### Horizontal Eave to Ridge Distance (W) — ft
> Horizontal Distance from Eave to Ridge. Consult ASCE 7 Section 7.6.1 for diagrams.
### Length of roof upwind of the drift (Lu) — ft
> Max out-of-plane distance to edge of roof. Used for determining the size and shape of snow drifts due to perpendicular-to-truss wind (see SBCA Load Guide Section C7.10.3 Note 4). Consult ASCE 7 Section 7.7.1 for diagrams of lu for generic snow drifts.
### Terrain Category
> Used to determine the exposure factor, Ce. Consult ASCE 7 Section 26.7.2 on "Surface roughness categories."
### Exposure Category
> Used to determine the exposure factor, Ce. Consult ASCE 7 Section 7.3.1 for roof exposure definitions.
### Risk Category
> Classifies buildings based on consequences of building failure. Consult the governing building code (cf. IBC Section 1604.5).
### Thermal Condition (Ct)
> Accounts for interior temperature of building. Consult ASCE 7 Section 7.3.2 for details.
When set to **Other**, the Roof R-Value, Ventilated, and manual thermal-factor controls below appear so the thermal factor can be derived from insulation properties.
### Roof R-Value — h·ft²·°F/Btu
> Roof insulation R-value. This can affect sloped roof snow loads and overhang ice loads. See ASCE 7 Section 7.4.
Shown when **Thermal Condition** is **Other**.
### Ventilated
> Roof ventilation can affect sloped roof snow loads and overhang ice loads. See ASCE 7 Section 7.4.
Shown when **Thermal Condition** is **Other**.
### Thermal Factor (Ct) & Manual Thermal Factor
> Override the calculated thermal factor with a value entered directly. Otherwise Ct is derived from the R-value.
Turn on **Manual Thermal Factor** to enter the value directly; otherwise it is derived from the R-value. Shown when **Thermal Condition** is **Other**.
### Winter Wind Parameter (W2)
> Value between 0 and 1 representing the fraction of the time between October and April that the wind speed exceeds 10 mph. This affects drift heights. See W2 in ASCE 7 Section 7.1.2 / 7.6.1.
Appears only for building codes referencing ASCE 7-22 or later.
### Snow DOL
> The load duration factor applied to snow load cases. See *Load Duration (DOL) Factors* below.
### Slippery roof
> Allows reduction of snow load (ps) if the roof is slippery and unobstructed. This requires sufficient space below the eaves to accept sliding snow. Slippery surfaces include metal, slate, glass, and bituminous, rubber, and plastic membranes with a smooth surface. Asphalt shingles, wood shingles, and shakes are not considered slippery. Consult ASCE 7 Section 7.4 for details.
### Sawtooth roof
> Enable to produce unbalanced snow load cases based on the roof shape as specified by ASCE 7 Section 7.6.3.
### Consider drifting snow (step drifts, parapets)
> Enable to produce drifting snow loads based on the roof shape as specified by ASCE 7 Sections 7.7, 7.8.
## Wind
Applies to roof components. Wind calculations follow the ASCE 7 edition tied to the building code, which affects the available enclosure options and the cited code clauses. Wind must be enabled before Tornado loads can be enabled; if Tornado is in use, it must be turned off before Wind can be disabled.
### Wind Design Method
> Selects the ASCE 7 procedure used to compute wind pressures: Components & Cladding (CC), MWFRS Envelope, MWFRS Directional, or a Hybrid Envelope/Directional approach.
### Wind Speed (V) — mph
> The design wind speed, in miles per hour.
### Enclosure Classification
> Classifies the building as Enclosed, Partially Enclosed, Partially Open, or Open, which affects internal pressure. Available options depend on the ASCE 7 edition and the selected wind design method (Partially Open requires ASCE 7-16+; Open is not offered for the Envelope methods).
### Terrain Exposure Category
> The terrain/surface-roughness exposure category used in the wind pressure calculation.
### Roof Shape
> The roof shape assumed for wind pressure coefficients (e.g., Gable or Flat, Hip, Mono). Selecting **Hip** reveals the flat-top-chord slope options below.
### Mean Roof Height — ft
> The mean roof height used in the wind pressure calculation, in feet.
### Roof slope for flat top chords matches that for sloped top chords
> When this is on, the roof surface attached to a truss's flat top chords will be assumed to have the same slope as the truss's sloped top chords.
Shown only when **Roof Shape** is **Hip**.
### Roof Slope for Flat Top Chords
> The roof slope assumed over a truss's flat top chords. Editable only when the option above is off. Shown only when **Roof Shape** is **Hip**.
### Horizontal distance to windward edge — ft
> The horizontal distance from the windward edge of the building to the truss, in feet.
### Directionality Factor (Kd)
> Load reduction factor accounting for wind direction. Default value of 0.85 can be applied to buildings, but larger factors are required in special cases, such as chimneys & trussed towers. See ASCE 7 Section 26.6.
### Topographic Factor (Kzt)
> Accounts for wind speedup at raised land features, such as hills and escarpments. Consult ASCE 7 Section 26.8.2 for in-depth calculations.
### Ground Elevation Factor (Ke)
> Accounts for reduced air density due to ground elevation. A value of 1.0 can be used for all elevations. Consult ASCE 7 Section 26.9 for elevation reduction factors (for pre-2016 codes, the commentary to Section 27.3.2).
### Gust Effect Factor (G)
> Accounts for rigidity of the structure. Factor of 0.85 is permitted for rigid buildings. Consult ASCE 7 Section 26.11 (26.9 for pre-2016 codes) for approaches to determining when a building is rigid.
### Wind DOL
> The load duration factor applied to wind load cases. See *Load Duration (DOL) Factors* below.
### Left / Right End Vertical exposed
> Indicates whether each end vertical is exposed to wind, affecting the wind pressure applied there.
### Left / Right Porch exposed
> Indicates whether each porch is exposed to wind, affecting the wind pressure applied there.
### Left / Right Cantilever exposed
> Indicates whether each cantilever is exposed to wind, affecting the wind pressure applied there.
### Building Width — ft
> The overall building width used in the wind calculation, in feet.
### Building Length — ft
> The overall building length used in the wind calculation, in feet.
### Max top chord dead load for uplift — psf
> The top-chord dead load used to offset wind uplift. Defaults to 60% of the top-chord dead load; press **Edit** to override it, or **Use Default** to restore the calculated value.
### Max bottom chord dead load for uplift — psf
> The bottom-chord dead load used to offset wind uplift. Defaults to 60% of the bottom-chord dead load; press **Edit** to override it, or **Use Default** to restore the calculated value.
## Tornado
Applies to roof components. This section appears only for building codes referencing **ASCE 7-22 or later**, and requires Wind loads to be enabled (tornado calculations reuse several wind settings such as terrain and enclosure).
### Tornado Speed (V\_T) — mph
> The design tornado speed, in miles per hour.
### Tornado Gust-Effect Factor (G\_T)
> The gust-effect factor used for tornado loads.
### Tornado DOL
> The load duration factor applied to tornado load cases. See *Load Duration (DOL) Factors* below.
### Treat building as Partially Enclosed for tornado loads (if Enclosed)
> Enclosed buildings with unprotected glazed openings may need to be reclassified as Partially Enclosed for tornado loads if breaches of some of the glazed openings would change the classification.
Selectable only when the wind **Enclosure Classification** is **Enclosed**. The resulting **Tornado Enclosure Classification** is shown read-only beneath it.
### Treat as Essential Facility
> Building is an Essential Facility or is required to maintain the functionality of an Essential Facility.
## Person Load
Applies to roof components and appears only for design codes using **TPI 1-2022 or later**.
### Person loading (if required)
> Applies a moving person load if required by the applicable design standard. See TPI 1 Section 6.2.2.5.
Even with this on, a person load is only generated where the design standard requires one. Paragon never considers person loading for floor components, for design codes older than TPI 1-2022, or for trusses spanning less than 18 ft.
### Use TPI Technical Advisory Committee Interpretation
> Applies the technical interpretation issued by TPI's Technical Advisory Committee to reduce or eliminate person loads in some cases. For details, see the interpretation document available from .
Editable only while **Person loading (if required)** is on.
TPI's Technical Advisory Committee issued an interpretation of TPI 1-2022 Section 6.2.2.5 that narrows where a person load has to be considered. With this setting on, Paragon applies a person load to a chord panel only as specified by the updated TPI TAC interpretation.
Turning this setting off returns to the more conservative reading of Section 6.2.2.5: every unsheathed top chord panel and every bottom chord panel on an applicable truss is loaded, without the clear-span, pitch, or clearance exemptions.
### Person DOL
> The load duration factor applied to person load cases. Capped at 1.6, per TPI 1-2022 Section 6.2.2.5. See *Load Duration (DOL) Factors* below.
## Attic Room
Applies to roof components. These settings describe a habitable attic room defined within the truss; they appear when **Attic Room** loading is enabled for the component.
### Floor Live Load — psf
> The live load applied to the attic room floor, in pounds per square foot.
### Floor Dead Load — psf
> The dead load applied to the attic room floor, in pounds per square foot.
### Wall Dead Load — psf
> The dead load applied to the attic room walls, in pounds per square foot.
### Ceiling Dead Load — psf
> The dead load applied to the attic room ceiling, in pounds per square foot.
### Room Width — ft
> The width of the attic room, in feet.
### Room Height — ft
> The height of the attic room, in feet.
## Sprinkler Installation Load
Available for roof and floor components. Appears when **Sprinkler Installation Load** is enabled for the component.
### Sprinkler Live Load — lbs
> The concentrated live load representing a sprinkler installation, in pounds.
### Apply along TC
> When on, the sprinkler load is applied along the top chord.
### Apply along BC
> When on, the sprinkler load is applied along the bottom chord.
## Drag Loads
Available for roof and floor components. Appears when **Drag Loads** are enabled for the component. A drag (lateral) load represents in-plane force the truss must transfer, such as from a diaphragm or shear wall.
### Total Drag Load & Drag Load Unit
> The magnitude of the drag load, entered either as a total force (**Pounds**) or a load per foot (**Plf**).
### Chord to resist on
> Selects whether the drag load is resisted along the **Bottom Chord** or the **Top Chord**.
### Side to resist on (for top chord)
> When the drag load is resisted on the top chord, selects the **Left** or **Right** side it is taken out on. Shown only when *Chord to resist on* is **Top Chord**.
### Drag DOL
> The load duration factor applied to drag load cases. See *Load Duration (DOL) Factors* below.
### Bottom Chord Horizontal Restraint Locations
> The start and end positions (and direction) of the bottom-chord restraints that resist the drag load. Shown for a single selected component when the load is resisted on the bottom chord.
## Load Duration (DOL) Factors
The **Load Duration (DOL) Factors** section lets you set the duration-of-load factor for each load type: **Dead**, **Floor Live**, **Roof Live**, **Wind**, **Tornado**, **Snow**, **Rain**, **Drag**, and **Person**. (The same factors appear inline in their own sections, e.g. *Snow DOL* and *Wind DOL*. Rain has no other setting and appears only here.)
> The duration-of-load factor applied to load cases of this type. Most factors range from 0 to 2.0 (the impact-load maximum, per TPI 1 Table 6.4-1); the Person factor is capped at 1.6, per TPI 1-2022 Section 6.2.2.5.
A reduced subset (**Dead**, **Roof Live** / **Floor Live**) is also available as **Basic Load Duration Factors** within the main roof or floor load section.
---
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