Building Design

This section covers the various design aspects, building footprint considerations, building codes, and various other factors that have been discussed with respect to the design of the new expansion. You'll find the data we have collected, along with our analysis and conclusion on these items.

The committee recognises the complexity of this project and is approaching this with a phased approach to building. This allows us to separate the complexities of remodeling the existing space and interior designs into separate phases. We can then focus on the building by looking at the utilization requirements/possibilities and developing a plan to allow the chapter to grow into this space.

Data-Driven Design

The committee examined the data from the 2020 Membership Survey to determine a list of desired features and amenities. Not included in this list are remodels, and improvements on existing functions provided by the current clubhouse. This distinction allows us to determine the necessary usable floor space needed to accomplish the various new functions being requested.

More Build Spaces
Pilot Lounge
Additional / Private Meeting Rooms / Classrooms
Self-sufficiency for our events
Parking for Show Planes / Guests
Library (Book/Video - Possibly with reading/viewing area)
Bigger Tool Room
More Storage Space (No more off-site storage)

Original clubhouse drawings as well as the 2017 South Hangar Expansion documents were reviewed by the committee to have an understanding of past efforts, the complexities, and help preempt and mitigate some of the past issues. These were digitized into a CAD model allowing us to visualize and study the proposed building designs in more detail.

We also considered chapter events and the flow of people through the building designs. For example, during the Fly-In and STOL competition we have have over 500 attendees entering the airport through our building. Our dinner events are capped due to existing space limitation in those hangars impacting those events throughout the year. Our Young Eagles, Teen Aviation Weekend, and other youth programs also pose unique requirements. These events & activities highlight some of the challenges that we face, and show that we at at or have exceeded our current building capacity to handle these events throughout the year.

Codes & Regulations Impacting Design

Building fire area cannot exceeding 12,000 sqft as it requires automatic sprinklers. For more details see the Firewall Code & Regulations section below.
Max building height limit on airport is 35 ft (ODA)
Max buildable land area is ~ 130ft wide x 63 ft (Gravel lot area). For details, see Buildable Footprint and ODA Land Lease sections below.
EAA National has a 10,000 sqft limit for chapter buildings per their insurance, however we have already discussed a waiver for this with them and are working on formalizing this.
Various other rules and regulations that govern the design of the building include:
- Oregon Structural Specialty Code (2022)
- Oregon Fire Code (2022)
- NFPA 70: National Electrical Code criteria
- International Fuel Gas Code (IFGC 2018)
- International Energy Conservation Code (IECC 2015)
- Oregon Mechanical Specialty Code (2022)

Design Options

For the building design, we examined options ranging from small to large. These designs were considered with regards to the functions we are wanting to add as well as codes and regulations that govern the limits of what is allowed to be built. These options were priced out with estimates to compare their cost-benefits and to help understand how the options would benefit the club both short and long term.

Clone

Dimensions: 45' x 63' x 16' Floor Space: 2835 sqft Price: $227,400

We first began by reviewing the 2017 expansion project as it provides a familiar design with well understood costs and complexities. It certainly added more build spaces for the chapter, and integrated well into the existing clubhouse. We considered cloning this building to the north end - a.k.a. the Clone (See figure 1 to the right).

The estimate includes filling out the center gravel lot with a paved surface, but does not include other improvements included in the cost of the other buildings such as skylights, and improved insulation, and necessary fire doors. The estimate, although high, is therefore slightly under budget.

The option leads with the lowest total price adding 30% more floor space to our clubhouse. The cost per square foot is around $80 dollars for a finished building complete with lighting & heating.

Although it provides additional build spaces, it provides little room to support the other desired functions being requested by the membership. Additionally, the center area utilization is reduced due to its diminished size and limited/no access from the north side.

Figure 1 - Clone - Copy of the 2017 South Hangar to the north side.

Half-Size

Dimensions: 63' x 63' x 25' Floor Space: 3969 sqft Price: $327,425

To support more of the functions the membership is desiring, we expand the width of the building to 63ft creating room within this new building to support expanded functions. The new space, which provides 40% more floor space than the clone, expands the list of functions the new building would be able to support including: ability to build a larger meeting room on the north end, hosting our own special events (dinners and forums) within our own building, accommodate parking of visiting show planes, and a portion could also be sectioned off as a possible pilot's lounge.

This option adds considerable support for many of the desired functions, but not simultaneously. The cost per square foot remains about the same as the Clone due to the added cost of the larger door and clear-span building. The added height allows parking of larger show planes such as the Bull Dog and enables room for sufficient ventilation supporting greater occupancy.

While the space allows for this additional functionality, it does require that build spaces are either temporarily or permanently displaced to accommodate these functions. i.e. we would could not host a dinner party without rearranging/displacing projects from the build space. The space also comes with the same disadvantages to the center area as the Clone.

Future expandability into the center space is heavily limited/restricted due to regulations.

Figure 2 - Half-Size - Expanded size with greater floor space to accommodate additional functions.

Full (a.k.a. Go-big)

Dimensions: 127' x 63' x 25' Floor Space: 8001 sqft Price: $382,650

Why not fill in the center space at the same time: The Full size building, a.k.a go-big plan maximizes the buildable space using up all the available lot space and leased land while staying within building code. This plan negates the need to expand in the future.

Although this plan is the most expensive of the three, it costs only 15% more than the Half-Size option while more than doubling the floor space (vs Half-Size); almost three times (2.8x) larger than the Clone. Total floor space for the clubhouse is expanded by 86% and provides space for all desired functions with additional capacity for future needs.

The plan allows Independence on reliance from other hangars for our events.

Figure 3 - Full - Maximizes the buildable space and provides room for future growth.

Comparison

For the design of the expansion, the committee examined several options for the building configuration. Based on these options, regulations and codes are being reviewed to determine impacts to the proposed design options. Additionally, configurations were priced out with estimates to examine their costs.

For a breakdown of costs, please see the Finance page.

Findings

Fixed costs such as permitting remain constant regardless of the size of the structure
Many of the costs do not scale linearly.
Usability of the center space is greatly diminished once a building is placed on the north end.
Limited ability to expand into the middle in the future due to code regulations. Specifically walk-way / egress paths required around the perimeter of the building prevents new structure from "filling-in" the center space. Any new building would need to be disconnected by a gap from the existing structures creating a discontinuity in the space.
While larger structures are more expensive especially when the clear span size increases, the cost per square foot greatly decreases with the Full size building.
Utilities may need to be pre-installed into the foundation if there are plans to expand later (water, drainage, power).
An additional building later on would carry many of the same costs duplicating things such as permits and engineering and other fixed cost line items.

Why is the Full size building 127 x 63 x 25?
The Full size building's footprint was derived based on maximizing the usable space while still conforming to all the codes and regulations. The allowable fire area primarily restricts the building from being any larger without substantial costly firewall additions to the existing clubhouse. The proposed firewall for the Full size building places an economical firewall minimizing not only the costs of that firewall but also of supporting requirements such as fire-rated doors. The exact maximum size is 127' 7-1/2" x 63' which is what the proposed Full size building is designed to.

How does the Full size building accommodate future improvements and modifications?
Similar to our current clubhouse, the interior space can be reconfigured and remodeled over time. Some of those modifications will be examined by the committee as future phases.

How will the club be able to afford the operating costs of the new building?
In addition to the added revenue generating opportunities (meeting rooms, build spaces, etc), the new building would be constructed using improved insulating materials to help reduce the utility costs.

Why do we need additional meetings rooms?
Less conflicts in scheduling meetings and gatherings.

How does the new building help us with our 501c3 requirements for Public Benefit?
Functions like the pilot lounge would considered as public benefits.

Why do we need additional storage?
Additional storage means we can keep all chapter assets in our building rather than spread around airpark.

Initial floor plan CAD drawings.

Download Floor Plan PDF

Blended Roofline

The existing clubhouse has a compound roofline as shown in Figure 1. The roof pitch of the existing buildings are 4:12.

The new building (regardless of it's final shape/size) will sit adjacent to these existing buildings, and the existing slope of the roofline will create a drainage issue. This area show in orange on Figure 2 will need to be modified to allow the water to shed away from the new structure.

The plan is to build the roof up to change the direction of drainage by raising the roof up using the existing truss structure. The trusses, which are located every 24", will be built up and the roof will be extended to blend with the new building as seen in Figure 3.

The roof pitch of the new building is planned at 2:12. The blend between the existing clubhouse and new building would also be at a 2:12 pitch.

Water Drainage

The current drain lines help return water to east side of the buildings and connect to the city drainage. This prevents water from shedding onto the ramp area. The new building would utilize the existing drainage, tapping into it from two gutters placed along the north and south edge of the structure.

If a smaller building is built, an additional drainage line would need to be installed into the foundation to support a new downspout on the south western edge of the building. Precautions would be taken when joining the buildings to avoid problems experienced from the 2017 expansion.

For the full size building, to control the water drainage between the South Expansion and the new building, an extended flashing would run along the groove helping to guide the water drainage to the existing downspout.

Note: During construction of the new hangar, we expect to improve and address any remaining issues with regards to water drainage on the existing South Hangar. This will be done when the new blended roof is installed. The existing issues is due to insufficient flashing where rain water can collect and enter below the flashing.

Figure 1 - Compound roofline of existing structures

Figure 2 - Roof section needing to be blended.

Figure 3 - Proposed blended roof line

Fire Code and Regulations

Per Oregon Fire Code, Section 903, fire areas greater than 12,000 square feet require an automatic sprinkler systems. The current city provided water line is insufficient in diameter to provided the necessary water volume/pressure for an automatic system. (2022 Oregon Structural Specialty Codes 306.2 / 903.2.4)

The existing clubhouse is nearly 9300 sqft and the addition of even the smaller design (Clone), which would add over 2800 sqft, would exceed the allowable limit.

For more details on the Oregon Fire Code, please see:
https://codes.iccsafe.org/content/ORFC2022P1/chapter-9-fire-protection-and-life-safety-systems

Note that fire areas are defined in section 901.4.4 as a building or portions of which are divided into areas that are separated by fire barriers constructed in accordance with Section 707.

Occupancy Group Classification
The occupancy group determines which fire codes apply to our building. Based on our mix usage, we may fall into the following categories: Groups A-3, Group B, E and Group F-1.

For a more info and details on the classification of occupancy groups, please see:
https://codes.iccsafe.org/content/IBC2021P2/chapter-3-occupancy-classification-and-use

Why can't we install an automatic sprinkler system?
The existing site does not have sufficient water delivery from the city line without upgrading the supply-line running along Airport Rd. Therefore a solution that requires an automatic sprinkler system is considered cost prohibitive due to these other required modifications.

What constitutes a firewall?
Per our occupancy group classification we are expecting to need a 2-hour firewall. Based on prior conversations with City of Independence inspectors, a 4-layer drywall with offsets studs would satisfied this code requirement. This wall must be extend upto the roof of the existing clubhouse.

Buildable Footprint

Before considering the building design options, we first had to consider the available space to build on. The chapter leases land from Oregon Department of Aviation as we are on a state owned airport. The land lease is based on a 5ft perimeter around the structure and requires certain offsets from adjacent buildings and airport functions. Given this, the buildable lot is primarily governed by the gravel lot behind our current clubhouse, with limits extending north towards Robin's hangar. The buildable space is limited to roughly a 130'
x 63' area.

ODA Land Lease

2023 lease - rented ground footprint is 11,511 SF
Ground Rent for 2023 11,511 X .2675 = $3,079

2024 ground rent cost will be $0.2857 per SF
New Ground Rent for current building - $3,289 a $210 increase.

Ground footprint to cover gravel area approx. 19,425 SF
- 111’ X 175’ = 19,425 SF (per drawing)
- 19,425 X $0.2857 = $5,550 per year
- The Full addition as proposed would add $2,260 for ground rent based on 2024 prices.

The board discussed (in 2023) leasing the gravel area from ODA regardless of expansion.
The gravel area is critical to EAA operations and the loss of it would be detrimental to the chapter.

We therefore consider the lease costs for land to be fixed regardless of size of expansion. A building the maximizes the usable space would have the greatest cost benefit from the leased land.