It’s a common conundrum: Your Denver bungalow was cozy when you bought it, but is downright cramped now that your family has grown—and spent the past year cooped up together inside. Do you sell it and hope to score a new house of your dreams in Denver’s competitive market—assuming the proceeds can cover the cost of sizing up in a city where the average single-family home price is quickly approaching $675,000? Or do you work with what you have by finding ways to stretch your square footage?

Justin Bride, principal of Ascent Contracting, Inc., has helped many clients navigate the latter path since founding his Denver-based residential and commercial contracting company in 2012, and has become a proponent of the practice along the way. “Popping the top gives homeowners the opportunity to have a brand-new house in a historic neighborhood or an area of town that they already have grown to love,” he explains. “Most of the time, people want to open up their whole first floor, and having that pop top to accommodate bedrooms really justifies creating the first-floor layout you’ve always envisioned. It gives you more of a blank slate so you can get what you want—a really functional and energy-efficient home where there wasn’t one before.”

Justin Bride, founder and principal of Ascent Contracting, Inc. Photo by Westward Photography

While many people associate popping the top with removing the entire roof to accommodate a full second story, Bride notes that smaller projects can have a big impact, too, from incorporating dormers to transform a partially used second floor into a spacious bedroom suite, to adding a back-of-house addition with a rooftop deck.

Imagining the possibilities is the easy part. For help with the practical considerations, we asked Bride to share his insights and advice:

5280 Home: What are the benefits of vertically expanding a home?
Justin Bride: Any time you add square footage to your home, especially in today’s market, you’re adding value to your property—whereas with an interior remodel, the value add may be more subjective. One of the reasons why [popping the top] is so prevalent in the city of Denver is that if there are site constraints—a smaller lot, or part of the site is already occupied by a detached garage, which you see all over Denver proper—sometimes it makes more sense to go vertical to get the square footage you want.

Does it cost less to build vertically? 
In terms of the price-per-square-foot cost for new construction, it’s similar to go up versus out. However, this cost is always closely related to the nature of the remodel—in particular, how much remodeling of the existing square footage needs to be done to accommodate the new square footage. Sometimes, a single-story, or even double-story, back-of-house addition can be less expensive than a pop top on a per-square-foot basis because the owners may not need to remodel their existing home, resulting in a lower overall project cost.

In Denver’s hot housing market, can homeowners expect to quickly recoup their investment in a pop top?
It would be fantastic if they could recoup all of their construction costs by the time the project is done. But it’s safer to hope that within two to five years, they will have recouped all of their construction costs and be net positive—with the understanding that everything is market dependent. We know that the property values of homes with pop tops we’ve done in 2016 and 2017 are already much higher than the owners’ total investments.

Before and After: A Sunnyside Pop Top

By Ascent Contracting, Inc., architect John Collins, and Studio 8.18 Engineering

Does popping the top take less time than expanding outward—or even starting from scratch?
Building a new house requires the longest timeline: When we do a scrape-and-build, we project 12-14 months, and sometimes they go over that. Our pop tops tend to fall below a year, but anymore—because there’s so much demand, not to mention the challenges of getting materials in the COVID world—below 10 months is a pretty aggressive schedule.

Building out [with a new addition] can have a similar overall timeline. Our back-of-house additions might peak at nine or 10 months and can be six to eight months. But with a back-of-house addition, the homeowner has the ability to live in the house for a certain portion of time. With a pop top, you really have to be out the entire time for everyone’s safety.

What are the structural requirements for a pop top, and does the typical century-old Wash Park bungalow meet them?
Many Denver houses, especially those that were built between the early 1900s and about 1930 or so, were really well built. Whether they have brick or concrete foundations, they can almost always accommodate a pop top. In the best-case scenario, if all the conditions are right and the house was built later than the mid-1920s, which was when they started to use concrete foundation walls with continuous footers, there doesn’t have to be anything done structurally to accommodate the pop top. But most of the time, it’s good to anticipate that light to moderate foundation support will be needed, in the form of helical piers or concrete pads.

Is it necessary to hire an architect?
For a pop top, an architect is really necessary because we’re adding square footage, there are rooflines and stairways to be considered, and most importantly, we’re stylistically blending old with new, which requires expertise. That’s not to say that a homeowner needs to start by engaging an architect. It’s just as good to engage a reputable contractor, who can then recommend an architect and start the project collaboratively.

Who hires the structural engineer?
The architect facilitates working with the structural engineer because structural design is typically part of the architectural design phase. The same is true with mechanical design, as in HVAC design. That wasn’t a necessity a few years ago, but in 2018, Denver began requiring a certain level of mechanical design with any project adding more than 30 percent to the existing square footage.

Before and After: A University Pop Top

By Ascent Contracting, Inc., architect John Collins, and Studio 8.18 Engineering

Speaking of rules, does zoning limit how much you can expand?
Absolutely. In addition to setback requirements, there are two big factors that come into play: Most of the Denver residential zoning classifications limit building coverage such that you can only have about 32.5 percent of your lot covered with a covered space. So, if you have a 10,000-square-foot lot, your house can only have a 3,250-square-foot footprint. If you have a two-story house, that’s 6,500 square feet. Most lots in Denver are more like 5,000 to 7,500 square feet, and so most houses with pop tops have them because their footprint was maxed out at around 2,000 square feet.

The other constraint is what’s called the bulk plane envelope, which you can visualize by imagining a tent, with 45-degree roofs, over a house. In most Denver residential zoning classifications, the tent can have a peak height of 30 feet, but at the property lines, the peak height is about 17 feet. The newly expanded house has to fit within that tent.

In Denver, do you have to bring the entire house up to code once you start adding on?
You have to bring every area of the house, or even wall of the house, that you touch up to code. But these codes aren’t just there to give government code-writers something to do. Most are really well written and make a lot of sense. The energy codes, for example, are written so people don’t have $400-per-month heating bills in the winter.

Are there other regulatory responsibilities to consider?
The homeowner typically doesn’t need to be concerned with [managing] things like plan submissions, building permits, and inspections, besides the time commitment that will be required. These days in Denver, the timeline from submitting plans to having the permit in hand is normally about three months. However, if the house happens to be a historic home or is located in a historic neighborhood, the project also has to be approved by the city’s Landmark Preservation Commission to ensure the addition will be built in accordance with the character of the neighborhood. That can add a good chunk of time.

It’s a big commitment. How can homeowners decide if it’s right for them?
We’ve had so many clients get into the process and realize it’s not worthwhile because their existing house just isn’t right for them, or because other neighborhoods make more sense, or because they just don’t want to go through the long, arduous journey to complete the project. But for the clients who do pull the trigger, the following are always the biggest reasons why:

Community. They have a strong bond with their neighborhood and neighbors, they love their schools and parks and local shops, and feel this is where they want to see their family grow.

Love for the process. Homeowners who really enjoy the remodels we get into are those who love going to showrooms and getting immersed in the world of options; people who really relish making those selections and being a part of it. For those who don’t like that process, the best thing to do is hire an interior designer. But it’s important to remember that every final decision still has to be made by the homeowner.

Creating a legacy. Clients who opt to pop the top often like the idea that the changes they’ll make will be enjoyed not just by their family, but potentially by generations and families to come.

A sense of history. This is where I get to be a little bit of a romantic. I love construction and imagining the skilled craftsmen who put their blood, sweat, and tears into building these homes. There’s a real piece of history in each one of these Denver homes. I love the idea of contributing to it, and good candidates for a pop top do too.