Are you planning on a new building or a tenant improvement. Wondering how many parking spaces do I need? Whether it is for a small office, retail, mercantile, restaurant or something even larger, like a large sport complex? Number of parking spaces ultimately comes down to how many users you have. Parking ultimately is determined by zoning laws however this blog will explain some rule of thumbs. Parking spaces can be quite costly however not providing enough spaces can also be costly as users could be turned off by a lack of spaces.
As an Architect, I interact with clients, engineers and contractors who have acquired bits of information about Building Codes. Sometimes, those bits are misconceptions and regurgitated information. The building codes can be intimidating and have no beginning or end. To learn the code, the best way is jumping in feet first.
Upcoming Blog Posts
In the next series of blog posts, I will explore common Building Codes. Each City has adopted a code but most in Arizona use the IBC (International Building Code).
The item in bold are addressed in this post. As an Arizona Architect, most City’s jurisdictions work with the IBC (International Building Code). This code analysis is based upon the IBC.
How many parking spaces do I need?
When designing a building or renovating an existing building, having enough parking is crucial to the function of the building. However there can be a point where overbuilding parking can be costly. Parking takes up space on a site. On grade parking and parking structures have an associated cost per space.
Parking quantities can also be difficult to quantify for places that may have times of heavy use for special events. Buildings like a shopping center, may see an influx of parking during holiday shopping. Complexes like a strip mall that contain a church may see heavy use for a Sunday service but have lighter parking needs during remainder of the week. Therefore, there is not one correct number of spaces, but some rules of thumbs that one can follow to ensure that in most scenarios, parking can handle the average flow.
The Parking Space
Parking spaces range in size from (8 1/2 ft x 18 ft) to (9 1/2 ft x 18 ft.). The city jurisdiction will dictate however I prefer the wider spaces. Living in Arizona, surrounded by many trucks, providing a slightly wider space minimizes the possibility of door dings. On occasion, tandem parking is permitted for multi-family developments, however at a 9 1/2 ft width space.
In some jurisdictions, if double striped spaces are used in 50% of the spaces provided, parking space width can be reduced for the remaining 50% of spaces to 9 ft. Double stripes are typical 12″ wide. Some cities allow compact spaces when their are in excess of the required spaces at a size of 8 ft X 16 ft. Good for a mini cooper or Smart Car.
The Parking Drive Aisle
Parking aisle are typically 24′ in width for two-way traffic. This allows one to safely back out of a space and for fire truck maneuvering.
Parking quantity by use (refer to your local zoning code, however below is an example)
Residential
2 parking spaces per dwelling unit
Commercial
office, business or professional – 1 space / 350 sf
restaurant – 1 space per 100 sf
veterinary clinic – 1 space per 600 sf
As you can see, various types of uses determine the # of parking spaces required. Once that total number of parking spaces has been calculated, a specific number of ADA spaces will be required. One example is 1 space for the first 25, s ADA parking spaces for 25-50 et5c.
Also some municipalities after a specific size building will require a loading space. One example I found was no loading space for buildings under 15,000 sf. Buildings from 15,000 – 49,999 square feet require 1 etc.
Summary
When looking at a property and determining the number of parking spaces required, first look at the local Planning and Zoning requirements to determine the minimum number of parking spaces required. Also look at your use to make sure you have met your business needs. Remember that when a site has too few parking spaces or the layout of the site is not easy to move around, this may deter people from wanting to stop by to your business.
If you have any doubts before signing that lease or purchasing a property, consult with a trained design professional to ensure your project and business success.
Open stair tread design is very beautiful. They give the appearance of the stair floating. They give a light and airy feeling to a sometimes forgotten design element. Do you want an open stair tread in your design? Their are specific requirements for how large the tread needs to be, the minimum and maximum height between treads. Some of the most beautiful stairs have open stair treads. Can you use them in your next project?
Code Analysis – Open Stair Treads
Building codes sections about stairs are very lengthy. They go into detail about length and width of treads, where handrails are needed etc. The code is very clear when open stair treads are allowed . Per IBC 1011.5.5.3, Solid Risers “Risers shall be solid“. Their are a few exceptions to open stair treads.
Solid risers are not required for stairways that are not required to comply with Section 1009.3 provided that the treads do not permit the passage of a sphere with a diameter of 4 inches. (Interpretation – Essentially it means any stairway not required for the exiting of the building or one which is in excess of the required stairs can have open stair risers). Occasionally, you will see a commercial building with a grand stairway in a lobby that has open treads. I believe this is how they are able to achieve this. The 4″ diameter is the same rule of thumb for stair guardrails or guardrails at balconies. This is eliminate the possibility of a small child from slipping between the cracks. Never a good thing.
Solid risers are not required for occupancies in group I-3 or in Group F, H and S occupancies other than areas accessible to the public. The size of the opening in the riser is not restricted. (Interpretation – can occur in industrial, factory, hazardous and storage facilities. This is why you generally see them occur in those conditions.)
Solid risers are not required for spiral stairways constructed in accordance with Section 1011.10.
In residential applications, you will see the majority of the open risers stairs. Some defy gravity and cantilever off the walls. They can be a work of art within a space. This is why, architects push the design envelope in residential design when designing stairs. The IRC, Section R311.7.5.1, specifically states “At open risers, openings located more than 30 inches, as measured vertically, to the floor or grade below shall not permit the passage of a 4 inch diameter sphere. (Interpretation – Open treads allowable anywhere in a residence as long as their is not an opening greater than 4″).
Summary
Open stair treads can add a beautiful element to any architectural design. Can you use this design element? Current code does not allow it in some commercial applications. They are not allowed as a required exit in a commercial project. They are allowed in occupancies such as Industrial, factories, storage facilities and hazardous occupancies. Use them in any of your residential projects. As with all projects, Check with your local jurisdiction to ensure your projects success. As with all design elements, their are exceptions to the rules.
Should my door have panic hardware? – Building Codes
As an Architect, I interact with clients, engineers and contractors who have acquired bits of information about Building Codes. Sometimes, those bits are misconceptions and regurgitated information. The building codes can be intimidating and have no beginning or end. To learn the code, the best way is jumping in feet first.
Upcoming Blog Posts
In the next series of blog posts, I will explore common Building Codes. Each City has adopted a code but most in Arizona use the IBC (International Building Code).
The item in bold are addressed in this post. As an Arizona Architect, most City’s jurisdictions work with the IBC (International Building Code). This code analysis is based upon the IBC.
Should my door have panic hardware?
Panic hardware – ‘A device designed to provide fast and easy egress in an emergency. Where is it required by code?’
Panic hardware is required by code in a few locations. Use it in buildings for its ease of exit. The following are some basics on where it applies:
Doors serving Occupancy ‘H’ – Hazardous
Occupancy ‘A’ (Assembly) or ‘E’ (Education) where occupant load is > 50.
Electrical Rooms with equipment rated at 1,200 amperes or more and over 6 ft wide that contains switching devices or control devices.
Exception – Panic hardware not required for the following:
Main Exit in Occupancy A(assembly) where occupant load is less than 300.
In occupancy types B(business), F(factory), M(mercantile) and places of religious worship, the main exterior doors are permitted to be equipped with key-operating locking devices provided: 1. Locking device is readily distinguishable as locked. 2. Sign adjacent to door states “This door to remain unlocked when building is occupied”
Summary
Should my door have panic hardware? Use them in spaces with large amounts of occupants or in rooms with hazardous conditions. The purpose of panic hardware is to ensure safety and security of a building. Panic Hardware isn’t required in all Occupancy types. It does allow occupants an easy means of egress. Always verify with current codes or specialist to ensure that your condition is code compliant.
