Gas riser diagram questions, answered
Common questions from the Denver-area GCs, architects, and contractors we work with. Don't see yours? Start your project and ask us directly.
What is a gas riser diagram, and when does a Denver-area permit require one?
A gas riser diagram is a drawing of your gas piping system showing every run from the meter (the point of delivery) to the most remote appliance, with pipe sizes and the total connected load in BTUs. Denver-area building departments won't accept a gas permit application without one. You'll typically need a diagram for new construction, additions, ADUs, and any project that adds or relocates gas appliances. If gas piping is part of the permit, the diagram almost always comes with it.
Who is allowed to prepare and stamp a gas riser diagram in Colorado?
Mechanical engineers, some architects, and master plumbers can prepare a gas riser diagram. What sets a stamped diagram apart is the seal of a licensed professional engineer. It tells the building department that a licensed engineer has verified the pipe sizing. Your diagram from us is drawn and stamped by a licensed Colorado mechanical engineer, with a stamp accepted across Denver-metro jurisdictions.
What code does my gas diagram need to comply with?
Colorado adopts the International Fuel Gas Code (IFGC) statewide, and local jurisdictions adopt and amend it. Denver enforces its own amended version, the Denver Fuel Gas Code, based on the 2021 IFGC with Denver amendments. We size and stamp every diagram to the edition your specific jurisdiction enforces, so what you submit matches what your reviewer expects.
How long does it take?
Most residential projects are completed within two business days of submission. Larger or more complex projects can take longer, but we'll tell you up front. The whole service is built around keeping your permit timeline moving.
What does it cost?
Flat-rate pricing: $799 for projects under 4,000 square feet, $999 for projects over 4,000 square feet. No hourly billing and no surprises. You know your cost before you start. No payment is required to submit your project.
What do you need from me to start?
Your floor plans, a list of the gas appliances, and the BTU input for each appliance. We work entirely from your documentation and don't come onsite, so the cleaner your plans, the less we'll need from you. If your floor plans aren't to scale, we may ask you for a few dimensions or distances so the sizing is accurate. It's low-effort on your end, not zero, and we'll tell you exactly what we need.
Which Denver-metro building departments accept your stamp?
Our licensed PE stamp is accepted across Denver-metro jurisdictions. See our Service Areas page for the areas we regularly work in. If you're not sure about your specific department, just ask when you submit.
Can you size pipe for a tankless water heater, a new ADU, or an addition?
Yes. These are some of the most common projects we see. Adding a tankless water heater, building an ADU, or putting on an addition usually changes your total connected gas load, which is exactly what the riser diagram has to account for. Send us the appliance details and we'll size it correctly.