Two-level deck on a large home built by Premier Custom Builders near Pittsburgh

Home Additions · Pittsburgh & Western PA

Home Additions in Pittsburgh

Get the space you need without leaving the home and neighborhood you love. We design and build room additions, second stories, in-law suites and garage additions that look like they were always part of the house.

Large brick estate home with columns built by a Pittsburgh area home addition contractor

More Room, Same Address

Home addition contractors who make new space feel original

Home additions in Pittsburgh give a growing family, an aging parent or a busy home office room to breathe, and an addition usually makes more sense than buying land and starting over, since your lot, utilities and foundation are already in place. The hard part is the tie-in: matching rooflines, siding, trim and floor heights so the new space reads as part of the original house.

As a design-build contractor, we handle the drawings, engineering, permits and construction with one team. Owner Joe Donati brings more than 20 years of building experience to every project, and our custom carpentry is done in-house, so millwork and trim in the new rooms can match what you already have.

  • ✓ Design, permits and construction under one contract
  • ✓ Rooflines, siding and trim matched to your home
  • ✓ Custom carpentry and millwork done in-house
  • ✓ Registered Pennsylvania contractor, PA HIC #028559

The Process

How a home addition comes together

Most additions take several months from the first design meeting to final inspection, and we set a realistic schedule for your project with your estimate.

  1. 1

    Design & Engineering

    We measure your home, sketch the layout and check that the structure can support what you want to build.

  2. 2

    Permits & Zoning

    We prepare the drawings your township needs for building and zoning approval, including setbacks and lot coverage.

  3. 3

    Build & Tie-In

    Foundation, framing, roofing and mechanicals, then the careful work of opening up and connecting to the existing house.

  4. 4

    Finishes & Walkthrough

    Insulation, drywall, flooring, trim and paint, then final inspection and a room-by-room walkthrough with you.

Out vs. Up

Building out or building up?

A ground-floor addition extends your home outward onto the lot. A second-story addition builds on top of the house you already have. Here is how the two compare.

Building Out Building Up
Structure New foundation, existing house mostly untouched Existing foundation and walls may need reinforcing
Roof Only the tie-in area is opened up Existing roof is removed and rebuilt
Living at home Usually possible with dust barriers Often easier to move out for part of the job
Yard space Uses part of your lot Keeps your yard, driveway and landscaping
Floor plan Easy access, good for aging in place New stairs take some main-floor space
Best fit Most lots with room to grow Tight lots or strict setback rules
Single-story stone ranch home in Western PennsylvaniaTwo-story home with deck and stairs near PittsburghTwo-story brick estate home with columns in Western PALarge home with a two-level deck built by Premier Custom Builders

Types of Additions

The right addition for the space you need

Every addition starts with how you plan to use the room. A primary suite, a bigger kitchen, a home office and a garage all place different demands on the foundation, plumbing, heating and cooling, and the way the new space connects to the rest of the house.

As a house addition builder, we look at your lot, your home’s structure and your township’s rules, then recommend the approach that gives you the most usable space with the cleanest tie-in.

Home extensions & bump-outs

Push out a wall to enlarge a kitchen, bathroom or living room without a full new wing.

Second-story additions

Add bedrooms or a primary suite above your home when the lot has no room to grow outward.

In-law suites

A bedroom, private bath, living area and often a kitchenette, with its own entrance.

Garage additions

Attached garages that share a wall and roofline with your home, with room above for a bonus space.

Hallway with a sliding barn door and custom trim in a home built by Premier Custom Builders
Hallway and dining area with glass-front cabinets in a Western PA home

Multigenerational & Modular

Multigenerational home additions and modular options

More families around Pittsburgh are bringing parents, grandparents or adult children under one roof. A multigenerational home addition gives everyone privacy and independence while keeping family close, with features like a separate entrance, a step-free entry, wider doorways and a walk-in shower for aging in place.

Modular home additions are built in sections off-site, then set on a foundation we prepare and finished on-site. They can shorten time on site for some projects, though the design choices are more limited. We will walk you through whether a modular or traditionally framed addition fits your home, your lot and your goals.

  • ✓ In-law suites with private entrances
  • ✓ Accessible, aging-in-place layouts
  • ✓ Modular additions set and finished on-site
  • ✓ Trim and finishes matched to the main house

Our Work

Rooms and finishes we build

Wide view of a kitchen with island and arched windowBathroom vanity with mirrorsHallway with a sliding barn doorDining area with glass-front cabinetsDeck with stairs on a two-story home near Pittsburgh

Related Services

More ways we can help with your home

Questions

Home addition FAQs

Is it cheaper to build out or build up?

For an existing home, building out with a ground-floor addition is usually less expensive and less disruptive than building up. A second story often means reinforcing the foundation and walls, removing the roof and extending heating, cooling and plumbing upstairs. Building up still makes sense on tight lots or where setbacks leave no room to expand outward.

How long do home additions in Pittsburgh take?

Most home additions take several months from the first design meeting to final inspection, and larger or second-story additions typically take longer. Design, township permits and construction each take their own stretch of time. We set a realistic schedule with your estimate so you know what to expect.

Do I need a permit for a home addition in Pennsylvania?

Yes. Any addition that increases a home’s floor area or height needs a building permit under the Pennsylvania Uniform Construction Code, along with a zoning review for setbacks, height and lot coverage. Electrical, plumbing and mechanical work usually need their own permits, and adding a bedroom on a septic system may need a sewage review. We prepare the drawings and handle the permit process for you.

Can you live in a house while an addition is being built?

In most cases, yes, especially with a ground-floor addition or bump-out where most of the work happens outside the existing walls. Expect some noise and dust, and short utility interruptions when the new space is tied into the house. With a second-story addition, many families choose to stay elsewhere during the roof and tie-in stages.

Is it cheaper to build an addition or buy a bigger house?

An addition is usually the more economical way to get more space, because you already own the land and the utilities, driveway and much of the infrastructure are in place. You also avoid the costs of selling, buying and moving. The right answer depends on how much space you need and what your lot and home can support.

What is included in an in-law suite addition?

A complete in-law suite typically includes a private bedroom, a full bathroom, a living or sitting area and a separate exterior entrance. Many also have a kitchenette or full kitchen and a stackable washer and dryer. Accessibility features like step-free entries, wider doorways and walk-in showers are common for aging parents.

Is an attached or detached garage better?

An attached garage addition usually costs less to build because it shares a wall, roofline and utilities with the house, and it gives you covered access straight indoors. A detached garage offers more freedom in size and ceiling height and keeps noise and fumes away from living areas. We can help you weigh both against your lot and how you plan to use the space.

How much does a home addition cost?

Every home addition is quoted after we visit the site and review the scope with you. Contact us to schedule a consultation and we’ll give you a written estimate.

Where We Build

Home additions across Pittsburgh and Western Pennsylvania

Based in New Castle, we build home additions anywhere within about 90 minutes of our shop, covering the entire Pittsburgh area and the communities around it.

Premier Custom Builders
4471A Mitchell Road, New Castle, PA 16105
724-944-0920 · By appointment
PA HIC #028559

PittsburghNew CastleCranberry TownshipWexfordSewickleyButlerBeaverMoon TownshipMt. LebanonZelienopleMarsGibsoniaAllison ParkEllwood CityHermitageGrove CitySlippery RockMonroeville