“Should I Remodel Or Move?” A St. Louis Homeowner’s Guide to Making the Right Choice (2025)

I just got off the phone with a homeowner—let’s call her Emily—who was genuinely torn up about her family’s situation. She and her husband have a 2.5% interest rate on their Webster Groves bungalow, love their tree-lined street, and their three-year-old daughter walks to daycare every morning. But they’re expecting their second child in four months, and their 1,200 square foot, two-bedroom home is bursting at the seams.

With unease in her voice, Emily asked me the question I hear every single week at J.T. McDermott:

“Should I remodel or move? What makes financial sense?”

It’s not a simple answer. And with today’s interest rates hovering around 7%, limited housing inventory across St. Louis County, and construction costs still elevated from recent years, it’s more complex than ever.

Here’s exactly how we help St. Louis homeowners think through this decision, based on real numbers, thousands of projects, and honest conversations just like Emily’s.

The Three-Scenario Decision Framework

Most homeowners think they have two options when they ask the question: “Should I remodel or move?” But there’s actually a third path many people never consider. Here’s how to think about all three:

Your Best Path	Upfront Investment	Monthly Impact	Home Value Impact	Best If You’re…
Add 400 sq ft + bathroom	$225,000-$260,000	HELOC payment (~$1,500/mo at 8%)	Adds ~$100,000-$125,000 in value	Staying 10+ years, love your location, have strong equity
Sell and move to larger home	$50,000 closing costs + moving	New mortgage ~$800-$1,200/mo higher	N/A	Want turnkey solution, staying 5-7 years, need different neighborhood
Keep as rental + buy new home	Refinance costs + down payment	Rental income offsets new mortgage	Build long-term wealth	Have great rate, home would rent well, think long-term

Now let’s break down how to know which path is right for you.

Understanding Addition Costs in St. Louis (The Real Numbers)

This is the part most homeowners have never researched, and that’s completely normal. But understanding actual costs is critical to making a good decision.

For a professionally designed and built addition with proper engineering, architectural integration, windows, utilities, high-quality finishes, and all permits, here’s what you’re looking at in the St. Louis market:

Small Addition (Living Room, Office, or Playroom)

$175,000–$220,000+

• 200-300 square feet
• Matches existing exterior closely
• Electrical and HVAC added (typically a mini-split)
• Foundation, framing, insulation, drywall, flooring, roofing, etc
• Fits on lot appropriately and meets all code requirements (energy, etc)

Addition with Full Bathroom

$225,000–$260,000+

• Same as above, plus plumbing rough-in
• New bathroom fixtures and finishes
• Ties to existing plumbing systems – potentially work in basement or crawl to do this
• Typically 400-500 square feet total

Second-Story Addition

$400,000–$600,000+

• Requires structural analysis of existing foundation/structure
• Often requires temporary relocation (3-4+ months)
• Stairs, additional HVAC zone
• Roof removal and reconstruction
• Most complex type of addition
  
  

A word on pricing: These numbers aren’t unique to McDermott Remodeling. Any legitimate design-build firm in St. Louis—whether it’s Mosby, Killeen Studio, Sandberg, or others—will be within 10-20% of each other because the actual work required is the same. If someone quotes you $100,000 for a 400-square-foot addition with a bathroom, there are likely significant things missing from that scope.

St. Louis Neighborhood Considerations

Where you live matters significantly:

South City Bungalows (The Hill, Lindenwood Park, Southampton) These 1920s-1940s homes often have basements and simpler roof lines, making additions somewhat more straightforward. However, many have knob-and-tube wiring and old plumbing that needs updating when walls are opened.

Central West End / Skinker-DeBaliviere Older homes with complex architecture and strict historic district requirements. Additions must match existing character, which adds design complexity and cost.

Clayton, Ladue, Town & Country, Chesterfield, Creve Coeur Larger lot sizes give more flexibility, but these neighborhoods have higher finish expectations. Your addition needs to match the quality level of surrounding homes.

Webster Groves, Glendale, Kirkwood, Maplewood Mix of bungalows and ranches. Great for additions, but municipal code requirements vary significantly. You will need an architect or an engineer and will need to pay attention to exterior finishes and the percentage of green space on the lot.

Why Additions Almost Never “Pay for Themselves”

Here’s the truth that most remodelers won’t tell you:

Additions rarely return their full cost when you sell.

Let me show you the actual math with a real Webster Groves example:

Your home today: Worth $350,000 (3 bed, 2 bath, 1,200 sq ft)
Addition cost: $225,000 (adds 400 sq ft + full bathroom)
Your total investment: $575,000
Appraised value after: $450,000-$475,000
“Loss” on paper: $100,000-$125,000

But here’s the reframe: If you’re staying 15 years and that addition gave you a home office, a playroom for your kids, and a second bathroom so you’re not fighting for the shower every morning, you’ve essentially paid $555/month ($100,000 ÷ 180 months) for a dramatic quality of life improvement.

For many families, that’s absolutely worth it. For others, especially those moving in 3-5 years, it’s not.

The stay-put timeline:

• 10+ years: Additions and major renovations make sense
• 5-7 years: You need to carefully evaluate the numbers
• Fewer than 5 years: Moving is almost always the better financial choice

How You Would Actually Pay for This (And Why Banks Say No Sometimes)

Most homeowners fund additions using:

• Home equity line of credit (HELOC)
• Cash savings
• Cash-out refinance
• 203(k) renovation loan
• Home equity loan

But here’s what catches people off guard: Lenders have limits based on your home’s after-improved value.

Banks typically won’t lend you more than 80-90% of what your home will be worth after the addition. Using our Webster Groves example:

After-improved value: $450,000
Maximum loan (at 85% LTV): $382,500
Your existing mortgage: $250,000
Maximum you can borrow: $132,500
Addition cost: $225,000
Gap you need to cover in cash: $92,500

This is where many homeowners hit a wall. The math simply doesn’t work without significant cash reserves.

When Moving Makes More Sense (Emily’s Situation)

In Emily’s case, here’s why the math pointed toward moving:

1. Current home: 3-bedroom, 2-bath Webster Groves ranch worth $380,000
2. What they need: More living space—family room feels cramped, no home office, want larger kitchen
3. Addition needed: At minimum $200,000-$225,000 to add 400-500 sq ft family room + office space
4. After-improved value: Maybe $500,000-$520,000
5. Timeline: Planning to stay approximately 5-7 years
6. The problem: They’d spend $200K+ to gain space, but still wouldn’t have the layout they really want
7. Financing gap: Would need $60,000+ in cash after maxing HELOC

But here’s what changed the conversation: We ran the numbers on keeping her current home as a rental.

The “Keep Your Home as a Rental” Strategy

Important caveat: This strategy only works if you have the cash available for a down payment on your new home, or if you can refinance your existing home to convert it to a rental property loan. Many homeowners don’t realize that most lenders require 20-25% down on a new primary residence if you’re keeping your current home. Additionally, being a landlord comes with responsibilities—maintenance calls, repairs, tenant management, potential vacancies—that aren’t for everyone. Factor in 10-15% of rental income for ongoing repairs and maintenance.

Her 3-bed, 2-bath Webster Groves ranch would rent for $2,600-$2,800/month. Her current mortgage payment is $1,750/month (thanks to that 2.5% rate). That’s $850-$1,050/month in positive cash flow.

Here’s the strategy we mapped out:

1. Keep the current home, keep the incredible 2.5% interest rate
2. Use available equity ($120,000 available) for down payment on larger home
3. Rent current home to cover its mortgage plus generate $850-1,050/month passive income
4. Buy a 4-bedroom, 3-bath home with better layout in nearby neighborhood
5. Build long-term wealth while getting the space and layout they actually want today

The real math: That rental income ($850-1,050/month) essentially subsidizes $200-250/month of their new mortgage payment. Over 10 years, that’s $102,000-$126,000 in rental income, plus they still own an appreciating asset. Meanwhile, they’re living in a home that actually fits their family’s needs.

Keep in mind: You’ll need to budget for property management (typically 8-10% of rent if you hire it out), occasional vacancy periods, and unexpected repairs like HVAC replacements or roof issues. Not everyone wants to be a landlord, and that’s perfectly okay—this strategy isn’t for everyone.

For many St. Louis homeowners with sub-3% interest rates, this is the smartest financial move of all. You’re not “losing” your rate, you’re leveraging it.

When an Addition DOES Make Perfect Sense

There are absolutely situations where building an addition is the right choice:

You should strongly consider an addition if:

✓ You’re planning to stay 10+ years (or indefinitely)
✓ You have strong equity or cash reserves available
✓ Your home already has 3+ bedrooms and 2+ baths (good foundation)
✓ You genuinely love your home, neighborhood and location
✓ The addition solves a daily frustration (not just adds space)
✓ Your lot can accommodate the addition without sacrificing yard
✓ You’ve maxed out interior remodeling options

Real example where an addition made sense:

A Sunset Hills family with four kids in a 4-bedroom, 3 bath home. They loved their street, excellent schools, family was close, they had been there for several years. They added onto their kitchen to create a dining area and a drop zone/additional storage for $305,000. Plan to stay another 10-15 years minimum. This was a perfect fit.

“Couldn’t We Just Hire a Cheaper Contractor?” (What You Need to Know)

Yes, you absolutely could hire a less expensive contractor. And for some homeowners, that’s the right call. But you need to understand exactly what you’re trading off.

Here’s what typically gets cut when a bid comes in 30-40% lower:

No pre-construction investigation – Walls aren’t opened (we inspect with a scope tool) before estimating, so surprises become change orders
Basic structural approach – May not properly tie into existing foundation or framing
“Allowances” everywhere – Flooring, fixtures, trim all listed as “allowance TBD,” which always goes over
Contractor-grade finishes – Not bad, but noticeably different quality than design-build firms
You manage everything – Separate architect, separate engineer, you coordinate some or all trades
“Contractor to verify” notes – Risk gets shifted back to you throughout the project

When a lower-cost approach might work:

• You have construction experience yourself
• You’re willing to act as your own general contractor
• The addition is very simple (single-story, no bathroom)
• You have time to manage multiple subcontractors
• You’re comfortable with some finish-level compromises

When it’s risky:

• Addition connects to tricky existing structure (common in older St. Louis homes)
• You need to live in the home during construction
• Structural unknowns are likely (pre-1960s homes)
• Your budget has no contingency cushion
• Timeline is critical

The connection between old structure and new structure is everything with additions. Cheap upfront often means expensive surprises later, especially in St. Louis homes built before 1970.

Your Decision Framework: A Simple Quiz

Answer these questions honestly:

1. How long are you planning to stay in your current home?

• 10+ years → Point toward addition
• 5-7 years → Depends on other factors
• Under 5 years → Point toward moving

2. What’s your home worth now, and what would it be worth after the addition?

• Addition adds 50%+ of its cost in value → Good
• Addition adds 30-50% of its cost → Marginal
• Addition adds less than 30% → Red flag

3. Can you comfortably fund the project without overextending?

• Yes, with equity/cash reserves → Green light
• Need to max out all borrowing → Caution
• Would need to compromise on other goals → Red flag

4. Does your home have good “bones” already?

• 3+ bedrooms, 2+ baths already → Addition makes sense
• 2 bedrooms, 1 bath → Moving often better
• Functional layout issues beyond size → Moving likely better

5. Is this really about the house, or the neighborhood?

• Neighborhood is irreplaceable → Addition makes sense
• Neighborhood is nice but flexible → Moving is viable
• You’d prefer a different area anyway → Move

If you scored mostly “green lights,” an addition likely makes sense. If you have multiple “red flags,” moving is probably your better path.

What Problems Could Go Wrong? (The Questions Homeowners Actually Ask)

“What if you open the walls and find major structural issues?”

This happens on about 15-20% of additions in older St. Louis homes. Common discoveries:

• Rotten sill plates from moisture
• Undersized floor joists
• No foundation footer where we need to tie in
• Knob-and-tube wiring that needs full replacement
• Termite damage in rim joists

This is why design-build firms open walls during the design phase before finalizing pricing. We’d rather find problems early when we can plan for them, not mid-construction when they become expensive emergencies. We cut pilot holes wherever possible. This doesn’t allow us to see everything, but it does expose a lot that can be planned for. A good design build project should have less than 2% of the cost be in “change orders” or surprises. 

“Can we actually live in the house during construction?”

Single-story additions: Usually yes, though it’s disruptive. Expect dust, noise from 7am-4pm, portable toilet on site, dumpster on site, and limited access to part of your house.

Second-story additions: Almost always requires moving out for 2-4 months plus. Your roof comes off, and living below active construction isn’t safe or practical. Also often requires work on the first floor.

Adding a bathroom: You can absolutely stay as you will still have access to your existing bathroom in most cases. 

“What if our neighbor complains about the addition?”

In St. Louis County, setback requirements are:

• 10 feet from side property lines (typically)
• 25-30 feet from rear property line
• Height restrictions vary by municipality

We always recommend talking to neighbors before starting, especially if the addition impacts their views or sunlight. Most disputes can be avoided with early communication with your HOA and the governing bodies. 

“What happens if we run out of money halfway through?”

You should know the costs up front in a fixed-price contract prior to moving forward with any construction contract. So this is not a scenario that should happen as long as you have the proper cash requirements and borrowing instruments (HELOC, etc) in place prior to starting. 

If You DO Decide to Move: What to Look For

If moving makes more sense for your situation, here’s what typically gives St. Louis families the best value:

Best value neighborhoods for growing families (2025):

High Value / More Affordable:

• Affton, Lemay, Oakville: Most house for your money, good schools, larger lots
• South County (Concord, Mehlville): Strong school districts, 1990s-2000s homes need less updating
• Florissant, Hazelwood: Undervalued, larger homes, improving neighborhoods
• St. Charles County (Wentzville, O’Fallon): New construction, great schools, family-focused

Established Neighborhoods (Higher Investment, Strong Resale):

• Webster Groves, Glendale, Kirkwood: Tree-lined streets, walkable downtowns, excellent schools, strong community feel. Expect $400K-$700K+ for move-in ready homes with the space you need.
• Clayton, Ladue, Town & Country: Premium neighborhoods with top-tier schools, larger lots, and homes that hold value exceptionally well. Budget $600K-$1.5M+ for homes that fit growing families.
• Maplewood, Richmond Heights: Great walkability, diverse communities, good restaurants and amenities. More affordable than Clayton/Webster but still a strong resale. $300K-$500K range.
• Chesterfield, Creve Coeur: Newer housing stock (1980s-2000s), excellent Parkway schools, larger lots with modern layouts. $450K-$800K for family-sized homes.
• Central West End, Skinker-DeBaliviere: Urban living with historic charm, walkable to Forest Park, great for families who want city amenities. $400K-$900K depending on condition and size.

What to prioritize when buying your “next” home:

• One more bedroom than you think you need (gives flexibility)
• 2.5+ bathrooms minimum for families
• Finished basement (adds functional space cheaply)
• Strong school district (helps resale even if you don’t have kids)
• Garage and storage (you’ll accumulate stuff)
• Open floor plan if possible (matches modern living better than choppy layouts)

Our Promise to St. Louis Homeowners

No matter what your answer is to “Should I remodel or move”, our goal is the same:

Give you the real information you need to make the best decision for your family—even if that means advising you not to remodel.

That’s exactly how we handled Emily’s call. After running through all the numbers, we told her honestly: “Based on your timeline, your current home size, and the cost of what you’d need to add, moving makes more financial sense. And if you can keep your current home as a rental, that’s probably your smartest long-term wealth-building move.”

She thanked us for our honesty. And when she’s ready for her next remodeling project in her new home—whether it’s a kitchen, a basement, or a bathroom—we’ll be the first call she makes. Because she knows we’ll tell her the truth.

Need Help Deciding Whether to Move or Remodel?

We offer free consultation calls where we can walk through:

✓ Addition costs specific to your home and neighborhood
✓ How banks evaluate remodeling loans and HELOCs
✓ Local comparable sales and value trends in your area
✓ Whether your planned changes actually solve your needs
✓ The “keep as rental” strategy and if it works for you

No pressure. No sales pitch. Just clarity.

We’ve helped hundreds of St. Louis families make this exact decision. About half end up remodeling with us. The other half thank us for our honesty and move forward with moving—and many come back later when they’re in their “forever home.” Instead of stressing about the question: “Should I remodel or move?”, give us a call for an honest evaluation!

Call us at 314-797-8215 or schedule a consultation at www.mcdermottremodeling.com

About J.T. McDermott Remodeling

We’re a design-build remodeling company serving St. Louis homeowners since 1995. We specialize in additions, kitchens, bathrooms, and whole-home remodels. Our approach: tell you the truth first, even if it means talking you out of a project.