"What will an addition actually cost?" is one of the hardest questions to answer in a text message, because it depends on so much. But homeowners deserve a real starting point, not just "it depends." Here is an honest, Utah County-specific breakdown.
I am Dakota. My crews have built home additions across Utah County for over 13 years, bump-outs, second stories, and full new wings, from older Provo and Springville lots to newer builds in Saratoga Springs and Eagle Mountain. Here is what actually drives the price.
Rough starting point: most Utah County home additions run $150 to $300 per square foot, depending on scope, finishes, and whether the new space includes a kitchen or bathroom. A simple bump-out lands toward the lower end. A second story with new plumbing tends to land higher.
Cost per square foot
Every addition is different, but here is the general range I quote Utah County homeowners, based on scope.
- Simple bump-out (no plumbing, basic finishes): roughly $150 to $200 per square foot.
- Standard room addition (bedroom, office, living space): roughly $180 to $250 per square foot.
- Addition with a kitchen or bathroom: roughly $220 to $300-plus per square foot, since plumbing, venting, and finishes drive the cost up.
- Second-story addition: roughly $175 to $350-plus per square foot for the new level, plus any structural work needed below it.
An example: an 800 to 1,200 square foot second-story addition with a bedroom and bathroom often lands somewhere around $175,000 to $350,000-plus depending on finishes. These are ballpark ranges for planning, not a quote. Every lot and every home is different.
Bump-outs: the smaller, more affordable option
A bump-out extends an existing room by a few feet, often for a bigger kitchen, a larger primary bedroom, or a bay window nook. It is usually the most budget-friendly type of addition because it does not require a full new foundation footprint or a full roof structure. If you love your layout but one room just feels too small, a bump-out is worth a serious look before jumping straight to a full addition.
Second-story additions: what people get wrong about the cost
A lot of homeowners assume a second story is automatically cheaper than a ground-floor addition since you are not paying for a new foundation. That is only part of the picture. A second story needs an engineer to confirm your existing foundation and main-floor framing can actually carry the extra weight. Sometimes that means reinforcing what is already there before we can build up. You are also temporarily without part of your roof during construction, which adds complexity most ground-floor additions do not have. Those factors often offset the foundation savings.
"Dakota did such an amazing job on my project. He handled all the subcontractors and would call me when they were coming next. The workmanship is excellent and I am very happy with the process and end result. Dakota was very easy to work with and always ready to answer my questions."
Vikki Masters · Full project, managed subcontractorsFoundation type and Utah County soil
Foundation choice matters more here than in a lot of places, because Utah County's soil is not the same from city to city. Newer growth areas like Saratoga Springs, Eagle Mountain, and parts of Vineyard sit on expansive clay or collapsible soils that shift with moisture. Building on soil like that without the right footing design can lead to cracking and settling years down the road.
A soil test before we design your foundation tells us exactly what your lot needs, whether that is a standard spread footing, a deeper footing, or in some cases a more engineered foundation system. It is a cost worth spending, since fixing a foundation problem after the fact costs far more than getting it right the first time.
Permits and city review
Any addition that adds square footage needs a building permit, plus sub-permits for plumbing, electrical, and mechanical if the new space includes them. Utah County cities each run their own permit desk with their own review timeline. Provo, Orem, Lehi, American Fork, and the rest each move at a slightly different pace, and unincorporated Utah County goes through the county office directly. If your lot sits in a newer development in Saratoga Springs, Eagle Mountain, or Vineyard, check your HOA's rules too, since many of these communities have their own review process for exterior additions on top of city permitting.
We handle the permit paperwork and factor realistic review time into your schedule so there are no surprises.
What drives your final number the most: whether the addition includes a kitchen or bathroom, whether it is single-story or a second story, and what your specific lot's soil requires for the foundation. Those three factors matter more than any other line item.
Utility lines and irrigation you might not think about
Many Utah County homes, especially in Spanish Fork, Payson, and other established areas, run on secondary or pressurized irrigation for the lawn, separate from culinary water. An addition that extends into the yard can mean rerouting a sprinkler line or a shared irrigation main, which is easy to plan for if we know about it early and a real headache if we find it mid-excavation. We locate utilities and irrigation lines before we ever break ground, so your addition does not turn into an unplanned sprinkler repair.
How long does a home addition take
Most single-story additions run 8 to 14 weeks from the start of construction, not counting design and permitting time up front. A second-story addition or one with a kitchen or bathroom typically runs longer, often 12 to 20 weeks, because of the added plumbing, electrical, and structural work involved. Permit review adds time before construction ever starts, and it varies by city, so we build a realistic full timeline into your written proposal, not just a construction estimate.
Get a real number for your addition
The only way to give you an accurate price is to look at your lot, your home's existing structure, and your goals for the new space. I will walk your property, talk through what you are picturing, and give you one honest, itemized price in writing.
See our home additions page for what we do, or check out home additions in Eagle Mountain and home additions in Saratoga Springs.