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.
Efficiency is important in office Design, whether it’s improvements to an existing space or a new building. Swinging doors are typical, however in certain applications, a sliding door is allowable by code and can improve the plan. Should you use a Swinging doors or sliding doors in your design?
Swinging doors take up room to allow for them to open and close. Sliding doors are more compact. A swinging door will open up to a wall. Doors can open 180 degrees against a wall, but in a smaller office, there may not be room for this to occur. Remember to provide the necessary clearances around doors as described in the post “Clearance around a door”. In a space with millwork or cabinets, a swinging door in its open position will affect accessibility to millwork. Below are a few scenarios.
Office Design with 90 degree swinging door
Office design with 180 degree swinging door
ADA compliance affected. Room will require more room to meet door clearances.
Office design with sliding door
Space is more efficient allowing for a more functional space.
The sliding door is much more efficient. If located properly, it allows for additional wall space where the door would swing to place more furniture or more maneuverability within the space
In locations such as a breakroom, millwork or other elements may conflict with swinging doors. In the two examples below, one layout shows where a sliding door will improve the functionality of the space.
Breakroom with swinging vs sliding door
When is a sliding door allowed?
There are a few instances where sliding doors are allowed by code. The following are some examples based upon the 2018 IBC codes. check your local jurisdiction for current code adopted and their interpretation.
Per section 1010.1.2 Door Swing. – Egress doors shall be of the pivoted or side-hinged swinging type. Exceptions where this doesn’t apply:
Private garages, office areas, factory and storage areas with an occupant load of 10 or less.
Group I-3 occupancies used as a place of detention.
Critical or intensive Care patient rooms within suites or health care facilities.
Doors within or serving a single dwelling unit in Groups R-2 and R-3.
In other than Group H occupancies, revolving doors complying with Section 1010.4.1.
In other than group H occupancies, special purpose sliding, accordion or folding door assemblies complying with Section 1010.1.4.3. This pertains to specialty doors which are power operated etc. Example of this is in grocery stores. The doors typical have the ability to hinge during a emergency or when the power disrupts the operation of the door and remains in a closed position.
Power-operating doors in accordance with Section 1010.1.4.2.
Doors serving a bathroom within an individual sleeping unit in Group R-1.
In other Group H occupancies, manually operated horizontal doors are permitted in a means of egress from spaces with an occupant load of 10 or less.
Items in blue, exception 1 and 9 pertain to office spaces.
There are various solutions for sliding doors. Ensure the solution you select meets ADA requirements. Acoustical properties is another factor to consider when picking the type of sliding door. A typical barn door will not have acoustical properties as it doesn’t have a seal at the opening, so if this is a concern, do some research on the type of door system. There are numerous examples of acoustical sliding doors. One example that has acoustical properties is AD Systems.
Summary
When planning your next office, determine if sliding doors would be a solution to make your office design more efficient. Will it save space and make it more functional. Follow the examples above for reference but as always, refer to the local jurisdiction, the current ADA guidelines and a local professional to ensure your projects success.
Are you planning on a tenant improvement and looking at leasing an existing space? Whether it is for a small office, retail, mercantile or restaurant in a small commercial space, is one bathroom enough? In a large building, may not big a big concern, as the percentage of area is minimal. When designing for a small spaces, Bathrooms take up valuable real estate. Some rule of thumbs when one restroom is not enough.
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.
When is one Restroom enough?
When designing a building, creating an efficient plan is important. Having extra space in an office, conference room, lobby, retail area or restaurant seating area is not a big problem. Who wants to have wasted space in bathrooms? It really becomes critical when designing smaller spaces.
The number of plumbing fixtures is dependent on the number of occupants. The code has formulas to determine the number of occupants based upon the type of occupancy. However in smaller spaces, lets say under 2,000 s.f., one might think one restroom would be sufficient. The code however indicates that separate restrooms are to be provided for each sex. There are a few exceptions:
Separate facilities shall not be required in structures or tenant spaces with a total occupant load, including employees and customers, of 15 or less.
Separate facilities shall not be required in mercantile occupancies (Retail showrooms) in which the maximum occupant load is 50 or less per IBC (International Building Code. Occupant Load of 100 or less in UPC (Uniform plumbing code). Therefore, it is a good idea to check with local jurisdiction which governs the project to determine what requirement
Shopping mall – In covered mall buildings, the required public and employee toilet facilities shall be located not more than one store above or below the space and path of travel shall not exceed a distance of 300 feet. Therefore, a central restroom facility can suffice. However, check with landlord requirements as they may require a restroom within the suite regardless of the central restroom facility.
Separate facilities (restrooms) shall not be required for dwelling units and sleeping units. In other words, residences.
Example Scenario
A.Business area (offices) – 1,600 s.f. Office space occupant load factor 100 sf/occupant (updated 10/2020) – codes are ever changing and in the IBC 2018, Business area occupancy changed to 150 sf/occupant with the exception per 1004.8 Concentrated business areas. The concentrated business areas are applied to uses such as telephone call centers, trading floors, electronic data processing or similar use business areas with a higher density of occupants. The number of occupants would then be calculated on ‘actual occupant load’ but not less than 50 sf/occupant.
2,400 / 150 = 16 occupants. This exceeds 15 occupants, therefore 2 restrooms are required. “”Note – check local code ammendments as this value of 15 may differ if overruled””
B. Restaurant – 1,300 s.f. 500 s.f. – kitchen & 800 s.f. dining area.Kitchen occupant load factor 200 sf/occupant & Dining area or assembly 15 s.f/occupant.
500/200 = 3 occupants & 800/15 = 53 occupants. Total of 56 occupants. This exceeds 15 occupants, therefore 2 restrooms are required.
C. Retail / Mercantile – 3,000 s.f. retail & 1,000 s.f. storage Mercantile load factor at 60 sf/occupant & Storage / Shipping area load factor at 300 s.f/occupant.
2,500/60 = 42 occupants & 1,000/300 = 4 occupants. Total of 46 occupants. This is less than 50 occupants, therefore 1 restroom is required.
Summary
When looking at an existing space to lease or buy that is fairly small, you may assume that 2 restrooms are most likely going to be required. In order for one restroom to be allowed, office space must be 2,400 s.f. or less, Mercantile space ~3,700 s.f. or less and Restaurant space dining area of ~150 s.f. with a kitchen area of 1,000 s.f. As you can see, in most scenarious, just plan on 2 restrooms. Follow the examples above for reference but as always, refer to the local jurisdiction, the current ADA guidelines and a local professional to ensure your projects success.
What is the Minimum size of a Bathroom? Does you current room meet ADA and building codes requirements? Are you building a new Bathroom and unsure of the correct size? Clearance and maneuverability is the driving factor to the size of a Bathroom. In a large building, may not big a big concern, as the percentage of area is minimal. When designing for a small commercial office or retail space, a Bathroom can take up valuable real estate.
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.
Minimum Size of a Bathroom?
When designing a building, creating an efficient plan is important. Having a little extra space in an office, conference room or lobby is not a big problem. Who wants to have wasted space in a Bathroom? It really becomes critical when designing smaller spaces. In retail or office spaces ranging from a few thousand square feet, a Bathroom can take up valuable real estate.
Size of a Bathroom depends on orientation of the fixtures and the swing of the door, swing meaning into the room or out. See “door swing direction” blog for more information.
A few rule of thumbs for Bathrooms:
Rule # 1– Doors shall not swing into the clear space or required clearance for any plumbing fixture. Fixtures would be mainly toilet and the sink. What is the clearance around a toilet or sink you may ask? They are as follows:
Sink clearance – 30″ wide x 48″ deep (shown dashed on floor plans below). Note – Knee clearance can extend under a sink 25″ maximum, assuming you have a wall hung sink.
Toilet clearance – 60″ wide x 66″ deep (shown dashed on floor plans below)
Rule # 2– Required clear floor spaces, clearance at plumbing fixtures and turning space shall be permitted to overlap.
Turning space – 60″ diameter circle within rest room.
Graphic examples of typical Bathroom with one toilet in varying configurations. Note that in all examples, door swing does not encroach on plumbing fixture clearances.
Minimum Size of a Bathroom
When swinging the door out of the room, it is possible to make the room the the smallest. I typically like to make the room just a tad bit larger than required by 1″ – 2″ to take into account construction tolerances and to make sure thickness of materials (ie. tile) or other unforeseen items don’t create a conflict.
Summary
When creating a new single person Bathroom, make it as efficient in size. Not only are you saving space in a building, it is more cost effective use of building materials. The ADA is a driving factor for the minimum size of a Bathroom. Plumbing fixture clearances are designed so occupants can easily use the restroom whether able bodies or in a wheelchair. Follow the examples above for reference but as always, refer to the local jurisdiction, the current ADA guidelines and a local professional to ensure your projects success.
Do I need a drinking fountain? 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.
Do I need a drinking fountain?
Do you ever wonder when you need an automatic drinking fountain in your office, your store, your warehouse?
The building codes IBC (International Building Code) and IPC (International Plumbing Code) both discuss when a drinking fountain is required. Local jurisdiction may have overriding amendments. The information below states the requirements as interpreted from the current 2018 IBC/IPC.
CODE
Drinking fountains are required in all occupancy types except:
Hotels
Motels
Boarding houses
Residential apartments
The quantity of drinking fountains vary dependent on occupancy type, however the range is from 1 per 100 to 1 per 1,000. The following are the basic requirements:
Drinking Fountain is not required in small occupancies per 2018 IBC/IPC for occupant loads less than 15.
Per City of Phoenix Code Amendments, Drinking Fountains are not required for occupant loads less than 50. – Check local jurisdiction to determine code amendments.
Where drinking fountains are required, not fewer than two drinking fountains shall be provided. One fountain to comply with wheelchair (36″ max. spout a.f.f.) and one for standing (~40″).
Exceptions or substitution:
Restaurants which provide drinking water for free are not required to have drinking fountains
Water dispensers shall be permitted to be substituted for not more than 50% of the required number of drinking fountains. (Interpretation – Drinking fountain with a bottle filler option, would satisfy the requirement for two drinking fountains).
Drinking fountains shall not be required in tenant spaces provided that public drinking fountains are located within 500 feet and not more than one story above/below tenant space.
In covered or open malls, drinking fountains shall not be required in tenant spaces provided that they are located within 300 feet.
Products
As water bottles have become more popular, bottle filling drinking fountain stations have become more prominent. In 2010, Elkay introduced a new drinking fountain. It was in response to consumer demand and environmental concerns of disposable bottles.
The product notifies the number of water bottles saved. Product notifies user to change filter as needed. This ensures and reinforces to the user that the water is safe to drink.
ADA
At least one drinking fountains installed must meet ADA requirements. Spout height at 36″ above finish floor maximum.
ADA sketch
The 2010 ADA standards does indicate, Section 211.2 Minimum Number – No fewer than two drinking fountains shall be provided. One drinking fountain shall comply with 602.1 through 602.6 and one drinking fountain shall comply with 602.7.
Exception: Where a single drinking fountain complies with 602.1 through 602.7, it shall be permitted to be substituted for two separate drinking fountains.
So what does 602.7 change to make it possible for one drinking fountain. Essentially the Spout has to be between 38″ minimum and 43″ maximum above the finish floor. This is higher than what is depicted in section 602.4 Spout height, which indicates 36″ a.f.f.
Summary
Do I need a drinking fountain? Drinking fountains are essentially required unless you have minimum occupants. Less than 15 occupants per IPC code and in some jurisdictions, such as Phoenix, less than 50 occupants. Where a drinking fountain is required, fixtures need to meet ADA requirements.
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.
