A-106 · Deliverables
The part of the job that outlives the equipment.
Air conditioning is the only major system in a house that routinely gets replaced with no record of why it was sized the way it was. Fifteen years later the next contractor stands in the same attic with the same lack of information and guesses again. We would like that to stop, so we write ours down.
What you are handed
A folder, and the same thing as a PDF. One copy goes in the air handler closet in a sleeve, because that is where the next person will look.
Nothing in it is proprietary and none of it is written to be hard to read. If you get three other quotes on the strength of our drawings, that is a fair use of them. We would rather compete against a contractor who knows what your house needs than against one who is guessing low.
Contents
A typical set
- M-001Cover & titleblock Address, date, who drew it, revision number, design conditions used.
- M-101Room-by-room load calculation Sensible and latent load per room, the assumptions behind each figure, and the whole-house total.
- M-102Equipment selection Model numbers, the AHRI match certificate, and the manufacturer's expanded performance data at our design conditions.
- M-201Duct layout Trunk and branch sizes, register types and locations, design airflow to every room.
- M-301Commissioning report Measured static pressure, total and per-room airflow, superheat, subcooling, and the technician's name and date.
- M-401Warranty & registration Manufacturer registration confirmations, our labour warranty terms, the permit number and the inspection sign-off.
Why it is worth something later
- When you sell. A buyer's inspector who can see the system was designed rather than swapped tends to write a shorter list.
- When something changes. Add a room, glaze in a porch, or replace the windows and the calculation can be revised rather than redone.
- When it eventually fails. Whoever replaces it in 2040 starts from measurements instead of the nameplate on a dead condenser.
- When we are wrong. If the house does not behave the way the drawing said it would, we have written down exactly what we expected, so the argument is about facts.
The honest limits
- A calculation is a model. It assumes your insulation is what it looks like from the attic hatch, and occasionally it is not.
- Blower-door and duct-leakage testing tighten the model considerably. We recommend both and we do not always win that argument on price.
- The commissioning numbers are true on the day they were taken. That is what the maintenance visits are for.
See a real set before you commit.
Ask and we will send you a full redacted drawing set from a recent Baton Rouge house, so you know what you would be buying.