Engenierring Drawing for Outdoor Wooden Steps

Stairs and Ramps

Stairs, ramps, elevators, and escalators provide access to different floor levels within or on the exterior of a structure. Stairs and ramps are often used in buildings three stories in height and less, whereas elevators and escalators are employed on buildings of four

Figure 9-1 Shop drawings are highly detailed assembly drawings done by a subcontractor. They show a designer's initial design and drawing with expanded views, descriptions, and construction details.

TRIM AT DOOR

BASE TRIM

MULL ION

TRIM e UJALL

184 top rail

MEAD TRIM a DOOR

134 bottom bail sheep

EXTERIOR ELEVATION

STAIRS

TOP OF HANDRAIL BETWEEN 34" TO 38' C8&5-9&5; ABOVE STAIR NOSING

MIN. 60° SLOPE TO RISER

OPEN RISERS NOT PERMITTED

top of handrail between 34'-3s' í0&5-9é>5; above ramp 9ura=ace inside handrail on turns must be continuous handrails omitted for clarity, but required on both sides of ramp runs when rise is over b' d5z>; or horizontal length is over 12" (18301.

NONCONTINUOUS HANDRAILS MUST EXTEND BETOND STAIRS AS SHOWN AND BE PARALLEL TO FLOOR.

HANDRAILS REQUIRED AT BOTH SIDES OF STAIRS INSIDE HANDRAIL MUST BE CONTINUOUS ON STAIR TURNS.

tí' (38; MAXIMUM PROJECTION

OPEN RISERS NOT PERMITTED

HANDRAILS REQUIRED AT BOTH SIDES OF STAIRS INSIDE HANDRAIL MUST BE CONTINUOUS ON STAIR TURNS.

tí' (38; MAXIMUM PROJECTION

Figure 9-2 Stair design and construction must meet building code and ADA requirements, including rules on configuration, width, risers, treads, landings, and handrails.

noncontinuous handrails must extend 121 í30sj as shoiln and be parallel to ground surface.

60" (1525} by 60" (1525; landing required f ramp changes direction.

noncontinuous handrails must extend 121 í30sj as shoiln and be parallel to ground surface.

60" (1525} by 60" (1525; landing required f ramp changes direction.

min. width 36' (9i5j top of handrail between 34'-3s' í0&5-9é>5; above ramp 9ura=ace inside handrail on turns must be continuous

handrails omitted for clarity, but required on both sides of ramp runs when rise is over b' d5z>; or horizontal length is over 12" (18301.

Figure 9-3 Ramps must be constructed in accordance with ADA guidelines and building codes. They provide physically disabled individuals with access to different floors.

min. width 36' (9i5j

Figure 9-3 Ramps must be constructed in accordance with ADA guidelines and building codes. They provide physically disabled individuals with access to different floors.

floors or more. However, in buildings such as shopping centers, which have high floor-to-floor dimensions and must accommodate a great number of people, escalators are commonly used. The design of stairs should place the least amount of physical strain on the people who use them, while reinforcing the design character of the space and structure of the building. Designs can range from major or monumental stairways to stairways that are strictly for utilitarian purposes.

Stairs are usually constructed from wood, steel, or concrete. Their design and construction must meet a number of building code and Americans with Disabilities Act (ADA) requirements for configuration, width, risers, treads, landings, and handrails (Figure 9-2). In many cases, a stair is augmented by a ramp that provides vertical transit for physically impaired individuals or ease of moving heavy objects (Figure 9-3). Interior design projects might involve the design and construction of a new stair or the remodel of an existing stair. Remodeling is often done to upgrade a stair in an older building to meet the current building codes or ADA requirements. Stairway Configurations and Terms

Stairs may be designed in a number of configurations to suit the amount of space available, the geometry of the layout, and the vertical/horizontal distance they must traverse. The most common stair configurations are shown in Figure 9-4. Their basic arrangements can be described by the following categories: straight run, right-angle run, reversing run, and some form of circular run. Figure 9-5 illustrates some of the most commonly used stair terms, defined below:

Baluster — the vertical components that hold the handrail. These are spaced to prevent people from falling through. These are governed by building codes and are

usually a maximum clearance to prevent a 4-inch (101.6 mm) sphere from passing through.

Guardrail — a rail that is used on the landings or floor levels to prevent people from falling between floor levels. It is usually a minimum of 36 inches high in residential and 42 inches high in commercial buildings.

Handrail — a continuous section of railing adjacent to a stair for a person to grasp as an aid when ascending or descending. Building codes closely control whether the railing is on one or both sides of the stair, its height above the floor, and other specifics.

Headroom — the minimum clearance between the edge (or nose) of the tread and any part of an obstruction above.

straight run

- MUST HAVE INTERMEDIATE LANDING F R-OOR TO H-OOR HEIGHT I» AOO^B a FT.

l-shape

- CTTEN USED IN COWERS

- RH OR FLIGHT CF STAIRS MAT BE EOUAL OR LKEOLLAL CN EACH SIDE OF LANDING

- U-9HAPE STAIRS ARE OFT» USED IN SERIES SUCH AS STAIRUAYS BemesN mant floors of

HIGH-RISE BUILDINGS

- USED PRIMARILY ONLY IN RESIDENTIAL, AS THEY CAN BE HAZARDOUS AND HOT PERMITTED BY MOST COMMERCIAL CODES AS AN egress STAIR

- USED WHEN THEFC IB NOT ENOUGH TOOM FOR AN L-6HAPE STAIR

- rwinieuasfireexitstairs

IN ac*-« CASES WITH AN AffROVED RADIUS

RESID^CES

- CAN BE DIFFICULT TO CARRY LAR5E OBJECTS UP « DOWN STAIRS IF SMALL RADIUS IS USED

- SPIRAL STAIRS CAN ^SEMBLE CUfWED STAIRS ILHEN THET HAVE A LARGE RADIUS

INTEWEI3IATE LANDINS -MINI. LENGTH EQUAL TO STAIR UIDTH

■SHAPED STAIRS CAN

■SHAPED STAIRS CAN

- MODIMCATIONS CAN \ BE MADB FOR STAIR \ FLIGHTS TO RJ4 IN \ M ANT DICTIONS-1

MOVIE STARS AFC É^TEN iSN UIALONG DOIIN T1-E8E STAJRS

■LANDINGS

OUADRANT <V4) OF THE CYLINDER

■LANDINGS

OUADRANT <V4) OF THE CYLINDER

SIDE < PLAN VIEWS

LANDw STAIR ¿AND 4 STAIR UAND&

iHffltirr nimiT i

Figure 9-4 Stairs can be constructed in a number of different configurations, depending on the amount of space available and the distance between floors.

plan view

Figure 9-5 (far left) Typical parts of a stair.

-STAIF» CAN f*e MADE MORE \ plan view MANAGEABLE BY OFFSET N3 T^E CCNVERSS^CE OF Tl-E COWCR STAIRS—

V L^DiNt

Landing — the floor or platform at the beginning or end of a stair, or between two or more stair runs. Newel — the terminating baluster at the bottom or top of a stair, which is usually larger than the other balusters. Nosing — the part of the tread that overhangs the riser, reducing the problem of a person accidentally kicking the riser as they ascend the stair.

Rise — the total vertical distance that is traveled on a stair. It is the perpendicular measurement between floor levels and the sum of all the riser heights. Riser — the vertical part of a stair between the treads. Run — the total horizontal depth of a stair, which is the sum of the treads.

Stringer — the structural support for the stair treads and risers. This is also referred to as a carriage. It might be exposed on a utilitarian stair, or hidden with various finishes on more decorative stairs.

Tread — the horizontal part of a stair that the foot bears down upon.

Winder - the wedge-shaped tread in a turn of the stairway run - found mostly in residential work, because commercial building codes restrict these.

Drafting Standards

The design and drawing details needed to illustrate a stair are dependent upon the complexity of the stair and the basic structural material it is constructed of. Stair systems are made primarily of wood, steel, or concrete. Wood stairs are mostly used in residential construction and are generally the simplest to draw and detail. Stairs are shown on the floor plans and called out as to their basic widths and number of treads and risers. The plan also shows the run and an arrow indicating whether the stairs go up or down from that level. Floor-plan views of stairs often cannot show all the materials and cross-sectional parts of their assemblies. Special stair sections (Figure 9-6) are often drawn to show the construction and finish details. In most cases, the designer does not have to draw every detail of a stairway and its many components. The fabricators of metal, concrete, and some wood stairs often make shop drawings. These detailed drawings are submitted to the designer for review.

Scale of Drawings

The scale of stairway drawings is generally V8" = 1'-0" (1:100 metric) or W = 1'-0" (1:50 metric), both in plan and elevation views. The number of treads and risers, as well as their dimensions, are called out here. Generic features such as the handrails and guardrails are also shown in both the plan and elevation views. Generally, handrails seen in elevation views are placed at a uniform height 30-34 inches (762-864 mm) above the stair nosing. In commercial projects with steel or concrete stairs, a large-scale drawing and stair section are required to fully explain these stair details and handrail/guardrail specifics. These are drawn at a scale of at least V2" = 1'-0" (1:20 metric) and cross-referenced to the floor plans.

To determine the number of treads and risers a stair must have, the vertical dimension between floor levels must be known. This vertical dimension is divided by the maximum riser height allowed by the building codes. At this writing, most residential stairs are limited to a maximum riser height of 8 inches (203 mm) and a minimum tread depth of 9% inches (235 mm). Commercial codes restrict the maximum height of a riser to 7 inches (178 mm), with

a minimum tread depth of 11 inches (280 mm). In a residential building, the typical vertical dimension might be 9'-10", or 106 inches (2.69 m). The designer divides 106 by 8 to find the minimum number of risers needed, which is 13.2. If only 13 are used, each riser will be slightly over 8 inches, which is not allowed according to the code. Rounding up to 14 will ensure each riser is slightly below the allowed 8 inches.

To find the total number of treads, remember that there is always one tread fewer than number of risers, as the floor levels at each stair end are not counted as treads. In our example, there would be 13 treads at 9 inches (229 mm) each, for a resulting stair run of 13 x 9" = 9 feet, 11 inches (3.02 m).

Figure 9-6 Stair sections are often drawn to detail out the construction and finish components, which are not shown in plan views.

plan.

Checklist for Stairways

General

• If a separate enlarged drawing is done for the stairway, key it and cross-reference to the floor plans.

• Show stairs in their entirety where possible, or use break lines where they continue on another floor level.

• Check stair widths, riser heights, tread widths, landing widths, and other particulars against the appropriate building codes and ADA requirements. Verify required dimensions and clearances.

Notations

• Call out direction of travel (up or down) on each section of stairway, and indicate with an arrow.

Dimensioning Stairways

Stairways are dimensioned on the floor plans as to their landing sizes, widths, and run of each stair, as seen in Figure 9-7. The total number and dimensions of the risers and runs are also shown on the plan. Vertical heights of the stair rise, handrails, and other particulars are dimensioned on a separate section or elevation drawing that is cross-referenced to the plan view (Figure 9-8). Designation of Materials

A stair's materials can be indicated in a number of different ways, depending upon how many materials there are and the size and complexity of the construction. Underlying structural materials might be called out with notes or shown in a sectional view. If the structural material is also the finished surface, this should be called out. If a separate finish material covers the stair, this might be called out in the section view, plan view, or on a separate finish

Figure 9-7 This enlarged plan of a stairway shows the dimensions of the landings, the widths and the run of each stair, risers, treads, and other details.

Figure 9-8 Stair sections show heights of the stair rise, handrails, and other details, cross-referenced to the plan view.

FIRST FLOOR STAIRIUAY

Figure 9-8 Stair sections show heights of the stair rise, handrails, and other details, cross-referenced to the plan view.

ENTRY

FIRST FLOOR

LOWER LEVEL

FIRST FLOOR

ENTRY

LOWER LEVEL

STAIR SECTION

• Note handrails and other trim. Key to where these can be found in more detail.

• Call out materials where stairs are shown in section view, including structural and finish components.

• Cross-reference to any structural plans where they are provided.

Dimensions

• Call out number and widths of treads, as well as number and height of risers.

• Dimension the total run of stairs in both plan and section views.

• Dimension the width of the stairs and any landings.

• Dimension treads, nosings, risers, landings, and handrail locations in sectional views of stairways.

Millwork

Architectural plans are often drawn at a scale too small to show adequate detail for cabinetry and millwork such as moldings, paneling, miscellaneous trim, and casings for doors and windows. These components are drawn and detailed at a large scale and cross-referenced to the basic plans. Millwork and cabinetry, also referred to as architectural woodwork, can include both manufactured stock components and custom woodwork that is assembled on the jobsite (Figure 9-9). Although some designers include cabinetry under the category of millwork, it will be treated here as a separate classification due to the specialized drawings needed to describe it.

Figure 9-9 This large-scale drawing shows the placement of stock-manufactured base cabinets.

T-3 TRIM

T-3S TRIM

MR-60

X4" PANEL ON %' H.D.F. ON %• GYP. BD. T-&4 TRIM

I" UJIDE x W DEEP WHITE MTL. GLAZING CHANNEL AND BLACK GLAZING GASKET. SHIM HDF AS REQUIRE TO HIDE CHANNEL.

FÜLL MIRROR

TILE:

FIBERGL'S SHOIUER

ELEVATION

MEN: THIRD FLOOR

Figure 9-10 Molding trim is produced in standard shapes and wood species, as noted in this section detail.

Continue reading here: Millujork Section

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Engenierring Drawing for Outdoor Wooden Steps

Source: https://www.northernarchitecture.us/construction-drawings/stairs-and-ramps.html