Functional design is not a list of features or products that are offered in custom home design. Rather, functional design is a list of decisions made prior to the breaking of ground for the new home. Where is your money best spent? How will people move through your new home? Which systems should be ‘locked in’ while they are still ‘inexpensive’ to change? Your wishes are translated into useful decisions that will still function well for you after you move in.
Budget allocation determines which functions survive
There is always a contraction phase in a custom home. Eventually the actual numbers just don’t meet the owner’s wishes and things need to get cut. Generally the things that are cut are those items that the owner thought would be ‘optional’ but were never prioritized. However, to protect the true function of the home, a prioritized list of all items that the owner desires should be developed prior to pricing out the home.
Prioritize your program and cut items on a first come-first served basis in the following order of priority, Tier 1 (must haves such as structural elements, buried items, etc.)/ Tier 2 (items that affect how you will use your home on a daily basis and can be ‘upgraded’ later)/ Tier 3 (items that are ‘optional’ and can be ‘picked out’ later such as flooring, paint, etc.).
Why cost per square foot misleads on function
When calculating cost per square foot for an irregularly shaped home, it is wise to take into account the higher cost per square foot of kitchens, bathrooms, and the spaces that contain the HVAC systems for heating and cooling. Then, allow for the remainder of the square footage to fluctuate as necessary to reach the target number for your custom home.
Floor plan decisions that carry the most weight
The quality of a plan is based on the circulation, adjacencies and daylighting of spaces prior to their square footage. An over-sized house plan is typically not as effective as a more compact, intense house plan.
Zoning and sound separation
Here’s another critical concept to apply to your home. Organize your house by noise/schedule rather than by floor. Meaning, if you have a master bedroom that is on the same wall as your living areas, you will begin to complain about that within a year. Laundry areas need to be isolated from bedrooms and be detailed out. If you have a mechanical room stacked under your sleeping areas, you need to pay close attention to the equipment placement and duct routing while the framing plan is under construction.
Storage located where the activity happens
Storage does not have to equal space. However the location of storage is critical to the functionality of the space. A functional plan positions a pantry near the garage for easy stocking of food and household items. Coat and bag storage near a family entry is better than storage in a remote location. The cleaning supplies for the home should be located on the floor where the majority of cleaning for the home takes place.
Choices that cannot be retrofitted cheaply
Note, Drain lines, conduit, even framed openings in walls have the unusual characteristic of costing only a very small percentage of the total budget of a home. And these items need to be “locked in” before the framing and envelope of the home are completed. The rest can be addressed as time permits.
| Feature | Must be decided by | Retrofit difficulty | Deferral strategy |
| Window size and placement | Permit drawings | High | None, decide early |
| Ceiling height and roof form | Permit drawings | High | None, decide early |
| Rough plumbing locations | Pre-slab or pre-subfloor | High | Stub out for future fixtures |
| Electrical circuits and low voltage | Pre-insulation | Moderate | Run conduit and extra boxes |
| HVAC zoning | Pre-insulation | Moderate | Size ducts for future split |
| Cabinetry and built-ins | Post-drywall | Low | Defer freely |
| Appliances and fixtures | Pre-final | Low | Defer freely |
Stub-outs and conduit as cheap insurance
In reality, drain lines, conduit, and even framed openings in walls cost only a small percentage of the overall cost of the home. Items such as a basement bath, generator or even solar power can cost the homeowner only a few hundred dollars to complete and need to be identified by the client as items that need to be completed and fit into the owner’s restricted budget for their new home.
Planning for the house to change
At CPI Custom Home Building in Greensboro NC, we build custom homes for people who plan to stay in their home for many years. While their needs may change in some important way before they move, we can design around one or two of those possible changes.
- One ground-floor room with a full bath nearby, usable as an office, guest room, or primary suite later
- Door openings and hallway widths at accessible dimensions throughout the main level
- Blocking in bathroom walls for grab bars, installed during framing and never seen until needed
- A stair location that allows a future lift or a second-floor separation
- Utility capacity sized above current load, including panel space and water heating
Sequencing decisions against the build schedule
Yes. Most of the function problems were decisions made too late in the process and therefore end up becoming a schedule problem. The typical new home builder of custom homes in Greensboro NC issues to the homeowner a “Selections Calendar” listing all of the homeowner selections and the time frame in which each selection needs to be made. If you are still comparing builders, it is worth reviewing how established firms that build custom homes in Greensboro NC structure that calendar before you sign anything. The time frames on the homeowner’s selections calendar become the real construction schedule and the builder counts on the homeowner to adhere to the contracted dates as if they were forecasted.
- Lock the plan and elevations before permit submission, since changes after this restart review
- Confirm plumbing fixture locations and appliance specifications before rough-in, not before installation
- Order long-lead items, typically windows, exterior doors, and custom cabinetry, as soon as the plan is final
- Walk the framed house before insulation and verify outlets, switches, and openings against actual furniture plans
- Reserve a contingency of roughly ten percent and release it only against documented changes
The homes of real value are the ones where the critical decisions were made early on in the process, and the homeowner views the schedule as a series of commitments and not something that can be changed along the way.
