Do You Need a Permit to Build a Deck in Colorado? Rules Cost and More

Have you got a big decking project in mind? Good for you! Getting a deck built or building your own deck can be a source of pride and joy for many homeowners. If your question is whether or not you need a permit to start, then do I have the info for you. Everywhere is a little bit different, but it’s good to have a look at the rules you need to abide by. That’s why we’re taking a closer look at the permit process in Colorado.

You will need to obtain a building permit to build a deck in the state of Colorado. You may require additional permits if installing a feature that has a connection to water, electricity, or gas. However, a small free-standing deck that is no more than 30 inches in height does not require a permit.

The process of obtaining a building permit for your deck is fairly similar across Colorado. There are also costs involved and consequences if you build without a permit, which I will explain.

Colorado Building Permits for Decking

After all the effort of planning and building a deck for your home, you definitely want to make sure it is up to code. Permits are required by law to ensure the safety of your home for you and any subsequent homeowners.

A four-year study revealed that, of all the injuries involving decking, approximately 19,690 cases were caused by structural failure or collapse. The local government is keeping up to date with the latest safety standards so that they can pass these standards onto homeowners when they apply for a building permit.

Each permit will be slightly different depending on what city you are living in. There are state guidelines for Colorado, but these guidelines branch out into each county and city. The best thing to do is to type into Google ‘building permit for a deck in [insert your city here]’, or browse your city’s government website.

The following is based on permit law from Fort Collins in Larimer County, however, all permits are derived from international standards. These are outlined in the International Residential Code (IRC) and the International Building Code (IBC), written by the International Code Council (ICC).

What You Will Need
The following list outlines what is required for the permit to be reviewed. It is your responsibility to gather these documents and provide them to your city council with your application form. 

  • Permit application form
  • Homeowner affidavit
  • Deck information/materials used
  • Site plan (where the deck sits on your lot)
  • Floor plan (house and decking)
  • Side view/elevation plan (shows the foundations and wall attachments if relevant)
  • Connection details (how you are connecting to the wall)
  • Photo of area where you plan to build the deck

This checklist has been taken from the Fort Collins Residential Deck Guide. Just remember that your specific city may differ slightly. In Fort Collins, these documents are all provided for you to sign and fill in. For the drawn plans of your deck, they give examples of what details you should be providing.

Cost
The cost of the permit depends on many factors. On average, you’ll be looking at somewhere around $225-$500 in Colorado.

Permit prices are based on the value of the deck as well as the services required during the inspection period. For example, if you need an inspection outside normal working hours, you will be charged around $50 per hour for the inspector. Or if you fail an inspection and need to repeat it, you will again be charged per hour for the inspector to come out.

You will also require additional permits for any gas, electricity, or water services.  For example, you may want to gas heater on the deck. These start at approximately $25 per permit.

The Process
Here is a step-by-step process of what you can expect when applying for a permit.

  1. Draw up plans for decking.
  2. Prepare all documents mentioned previously.
  3. Submit the application form with supporting documents and payment.
  4. Application is reviewed, including Historic Preservation review if your home is over 50 years old.
  5. Permit is issued and valid for 180 days. You can request one free extension period of a further 180 days. This should be displayed somewhere near the construction.
  6. Begin construction.
  7. First inspection when the setback and footings are established.
  8. Second inspection when the foundation is complete (the concrete piers and pillars are in place)
  9. Third inspection when the frame and any utilities are established (minus flooring of the deck).
  10. Final inspection when the deck is complete.

Rules for Building a Deck
There are many things to consider when designing your deck. By studying the rules specific to your area, you will save yourself the hassle of failing inspections and repeating each step of the building process. Below are a few of the rules you might find.

  • Guardrails: essential if the deck is more than 30 inches above ground. Guardrails should be a minimum 36 inches in height.
  • Stairs: Must be at least 36 inches wide. If more than four risers, stairs must have a 34-36 inch handrail. Risers can range between 4-7 ¾ inch and treads should be at least 10 inches. Stairs must be illuminated.
  • Piers: Concrete piers must be a minimum of 30 inches deep and 8 inches in diameter. Concrete should protrude at least 8 inches above ground. Anchor bolt should be embedded at least 7 inches into concrete. Wooden pillars must be treated to prevent corrosion.

These are the major rules regarding the construction of your deck. These rules may change as the ICC updates their codes every three years. There are also many finer details covered in the ICC’s building code, such as handrail specifications and joists. I suggest you look up the rules specific to your city immediately prior to planning so that you have the most up to date building codes.

Building a Deck without a Permit

Building a deck without a permit is risky. I’m sure there are people who have done it before, but rules have been tightening to ensure that those who have built without a permit are caught. Being caught means paying a hefty fine as well as other consequences.

However, if you are building a floating or ground-level deck, you do not require a permit. The floating deck must be free-standing (not attached to the house), no more than 30 inches high, and have less than 120 feet of flooring.

Regular decking that is not up to code may be reported by anyone. The deck may cause serious harm to someone, leaving you liable for their injuries and open to being sued. This is going to cost far more than getting a permit and having regular inspections.

Your insurance company will also refuse to pay for damages if they found out that your deck was built without a permit. So if you were to be sued, you’d be paying for everything yourself.

Decks that are up to code, but built without a permit, might go unnoticed. However, if you were to ever try to sell your home, you might be required to provide proof of obtaining a permit. 

Some financial institutions will insist on an inspection report before the purchase can be made. If there is no evidence that the deck was built with a permit, there’s a high chance you will be asked to dismantle it and start again. There’s also a chance that the value of your home will be forced down if buyers find out about it.

If you already have a deck that does not have a permit, you can obtain one for the existing structure. This process involves drawing up all the plans for the deck as if you were building it yourself, applying through your local city, and having an inspector look at it. 

If it is not up to code, which may have changed since it was built, you will be required to tear down the sub-standard sections and rebuild as directed by the inspector.

I’m sure the reason you’re reading this article is because you want to do the right thing when you build your deck. I hope you’ve found the answers you were looking for and enjoy the process of building your very own deck.

Click here to visit our Deck Building Services page to learn more about what we do.

Hey NoCo, interested in talking to someone here at TNT today about your project, give us a call at 970-663-2868. You can also reach us right here on the website for instant chat (bottom right) or email us at sales@tnthomeimprovements.com