Home additions and dormers in Frontenac, MO
Frontenac is a part of St. Louis County where homes were architect-designed. The mid-century moderns from the 1950s and 1960s, the contemporary homes through the 1990s and 2000s, and the recent custom builds all share an architectural sensibility that treats every line as intentional. An addition to a Frontenac home is rarely a casual project. It’s a design problem, and it has to be solved at the level at which the original was solved.
Why Frontenac, MO homeowners trust Aleto with home additions
Frontenac’s architectural housing stock spans several distinct vocabularies. Mid-century moderns, often single-story with flat or low-pitched roofs, deep eaves, and large glazing, designed in the international and contemporary idioms. Custom contemporary homes from the 1990s and 2000s that carry that DNA forward with current materials. Traditional homes from various eras, often built at higher design intent than typical subdivision construction. Recent custom builds in modernist, transitional, and revival vocabularies. Adding to any of these means understanding which vocabulary the home is in and designing the addition to belong inside it.
A Frontenac mid-century modern addition is fundamentally different from a Webster Groves bungalow addition. The mid-century home has horizontal emphasis, deep overhangs, walls of glass, and often a strong relationship to the landscape. The addition has to extend that vocabulary, not interrupt it. Pavilion-style additions connected to the original home through a glazed connector. Lateral expansions that extend the existing roof line. Detached studios or guest pavilions designed in the same architectural family. Anything that introduces a different vocabulary reads as a transplant and diminishes the home.
Aleto Construction Group has been working in Frontenac and across St. Louis County since 1955. As a design-build firm, we collaborate with outside architects and designers when clients have already engaged them, and we provide full design services internally when they haven’t. The construction discipline (tolerances, sequencing, shop drawing review, finish substrate prep) is the same regardless: appropriate to a home that was designed, not just built. Frontenac homeowners expect that, and we deliver to it.
What an addition in Frontenac, MO can include
Every project is scoped to the home and the homeowner. Here are the addition types we complete most often in Frontenac:
Pavilion-style additions
Lateral additions designed as architecturally distinct pavilions connected to the original home, often through glazed connectors that preserve the reading of both volumes
Glazed connectors and transitions
Glass-and-steel transition spaces between the original home and the addition are sometimes the most architecturally significant element of the project
Contemporary primary suite wings
Primary suite additions designed to extend mid-century or contemporary vocabularies, with horizontal emphasis, large glazing, and continuous roof and floor planes
Detached studios and guest pavilions
Standalone structures (artist studios, home offices, guest accommodations) designed in the home’s architectural family, often sited as deliberate landscape elements
Architect and designer collaboration
Building from outside architectural drawings and finish schedules, including shop drawing coordination, RFI management, and construction administration through the architect of record
Roof extension and re-formation
Extending or carefully re-forming the original home’s roof to integrate with addition volumes, requiring structural and waterproofing detail consistent with the original construction
Custom millwork and integrated finishes
Rift-cut and quarter-sawn casework, integrated lighting, recessed niches with stone reveals, and surface-applied plumbing valves with millimeter tolerances
Landscape integration
Addition siting that acknowledges existing landscape architecture, mature trees, view corridors, and the home’s existing relationship to the property
What additions look like in Frontenac, MO
Frontenac additions tend to be design-led projects in homes with strong architectural identity. Here are the scenarios we see most often.
Designing a pavilion that completes a mid-century home
A specifically Frontenac scenario: a 1962 mid-century modern with original architect-designed living spaces and an undersized primary bedroom. The right addition isn’t a typical primary suite wing tacked on to the side. It’s a deliberately designed pavilion, often one or one-and-a-half stories tall depending on the original home’s roof line, set lateral to the existing volume and connected through a glazed corridor. The pavilion gets its own architectural reading: clean rectangular volume, deep overhangs that match the original, large glazing oriented to a specific landscape view. Inside the pavilion is the new primary suite at full scale. The original home isn’t compromised; it’s complemented. Done well, this kind of addition reads as if the original architect had simply designed more of the home than was originally built.
Building from an outside architect’s drawings
Many Frontenac homeowners come to a renovation having already engaged an architect or designer. The drawings, finish schedules, and specifications arrive complete. Our job at that point is to build exactly what’s drawn, with construction-administration discipline: shop drawing review, RFI management, mockups for any condition that benefits from one, daily coordination with the architect, and submittal review for every long-lead specialty product. The relationship works best when the construction team treats the architect as a peer rather than as an obstacle. We build that way, and our scope of work documentation reflects the level of detail the construction has to hold to.
Holding architectural tolerance on the connection
The connection point between an existing home and an addition is where most additions are exposed. The original siding and the new siding meet. The original roofline and the new roofline transition. The original window proportions and the new window proportions sit next to each other and either relate or don’t. Frontenac additions, more than additions in any other St. Louis County market, have to land these connections precisely. A glazed connector that’s an inch too narrow reads wrong. A roof return that doesn’t match the original pitch within a degree reads wrong. The trades and the construction documents have to support that level of precision.
Adding a detached pavilion as a deliberate landscape element
Many Frontenac properties have lot space and architectural language that support a detached structure: a studio, a home office, a guest house, a pool pavilion. Designed well, the detached structure becomes a deliberate landscape element rather than a utility building. It’s sited to relate to the main house, the topography, the mature trees, and any existing landscape architecture. It’s designed in the same vocabulary at an appropriate scale. The path between the main house and the detached structure is itself a design move. We’ve completed these projects with both outside architects and through internal design, and the consistent characteristic is that the detached structure feels intentional, not auxiliary.
What our clients are saying…
“Aleto made our dream home come true and they made the four months renovation period smooth, pleasant, and seamless. Mike was a dream contractor – he kept in communication with us every single day. We received daily updates and he responded immediately to any and all messages we sent him. They hired the best workers, they worked with the best companies, and we could not be happier with our finished project. We recommend Aleto 100%.”
Mary – Houzz Review
Featured home addition project
Lindenwood Park Upgrade
A home in the Lindenwood Park neighborhood just got an elevated upgrade—literally. This second-story addition features a spacious owner’s retreat with a light-filled bedroom, a walk-in closet, and a beautifully tiled full bathroom.
Custom details include 5×5 ceramic wall tile, a 1″ hex mosaic floor with 2′ square rug insets, and warm wood-look LVP throughout. A custom staircase ties it all together with elegance and craftsmanship.
Frequently asked questions
Do you work with our architect or designer?
Yes, frequently. A meaningful share of our Frontenac work is design-build with an outside architect or interior designer leading the design effort. We treat the architect as the design author and ourselves as the construction author. That means we build to the drawings, raise RFIs when something needs clarification, propose alternatives only when there’s a real construction reason, and protect the design intent through the trades. Where clients prefer a single design-build relationship, we provide design services in-house at the same level.
Can you execute a contemporary addition with the precision the design requires?
Yes. Contemporary Frontenac additions are often designed with reveals, alignments, and tolerances that depend on careful execution. The slab joint has to land exactly where the drawing says. The connector roof has to match the original pitch within a fraction of a degree. The window head and the door head have to align across the threshold. None of this is hard for a construction team that takes it seriously and works with trades who understand the standard. Our subcontractor relationships and our construction administration practices are oriented to this level of work.
Will the addition respect the architectural language of our Frontenac home?
That’s the priority. The most common failure mode in Frontenac additions is a current-trend design that ignores the home’s actual architectural language, which dates the addition quickly and reads as a transplant. We start every project by understanding what the home is, architecturally, and design or build the addition as an extension of that home rather than apart from it. This applies whether the home is a 1960s mid-century, a 1990s contemporary, or a recent custom build.
More home renovation services in Frontenac, MO
Looking at a different scope? Explore our other services available in Frontenac, MO:
Kitchen renovation
We rethink how your kitchen flows, functions, and feels from layout to custom storage and premium appliances.
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Whole-home renovation
Full reimagining of your home from top to bottom, designed and built as one cohesive project.
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Bathroom renovation
Convert dated bathrooms into spa-like retreats with custom tile, modern fixtures, and intelligent layouts.
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Ready to add space to your Frontenac, MO home?
A home addition starts with a conversation about how your home isn’t working today and what it could become. Tell us what you’re thinking, and we’ll take it from there.