Skip to content
Wood framing for a room addition going up beside an attached garage

Home Additions

Room Additions in Ventura County

A new bedroom, a family room or an office built onto the side or back of the house, on our own foundation, framed and finished to match the rest of your home.

Get a Free Estimate Call (805) 921-0405
BBB Accredited Business A+ rating5.017 Google reviews

Request a Free Quote

Licensed CSLB #920095 · Free estimates

Room Additions

A ground-floor room addition is the most straightforward way to add space. The new room sits on its own foundation, connects to the house through an existing wall or a new opening, and gets a roof that ties into the existing one. Because nothing is built on top of the existing house, the old structure usually needs less reinforcement than a second story would.

The two big questions are where the room can go and how it connects. Zoning setbacks and lot coverage decide the first. The existing roofline, floor height and room layout decide the second. We check both at the first visit, before you pay for drawings.

Where an addition can go

Every lot has setbacks from the front, side and rear property lines, and limits on how much of the lot can be covered. On a typical tract lot, the back yard is the most common place for an addition, with side additions possible on wider lots. Easements for utilities and drainage can also block an area. We look at your lot survey or measure the property, then confirm the rules with your city or the County.

Tying the new room to the old house

Matching floor heights avoids a step between old and new. In a raised-floor house, the addition can be built on a raised floor too; in a slab house, the new slab is set to match. The roof is the trickiest connection: the new roof has to shed water past the old one without a low spot, and the roof pitch and eave details should match from the street.

  • Foundation

    Footings and slab or stem walls poured under our C-8 license, designed for your soil.

  • Roof tie-in

    Framing and flashing that carry water away from the joint between old and new roofs.

  • Exterior match

    Stucco texture, siding, windows and trim chosen to match the existing house.

  • Heating and cooling

    Extending existing ducts if the system can handle it, or a separate system for the new room.

What adds cost

Plumbing is the biggest cost difference between room types: a bedroom or office costs less per square foot than a room with a bathroom. Soil conditions that need deeper footings, a long distance to the electrical panel, and exterior finishes that are hard to match also add cost. California school districts charge a fee on residential additions over 500 square feet, so a slightly smaller addition can save that fee.

From our clients

Real Google reviews from LE Construction clients, quoted word for word.

EXCELLENT

5.0 out of 5, based on 17 Google reviews

  • Richard Torres

    April 2024 · Google review

    "All work was constructed via architect design. We eliminated a bay window and slider and extended an exterior wall making room for a stand alone tub and facilities relocation to accommodate more closet space. All new tile was installed throughout."
  • Oscar A. Ramirez

    February 2025 · Google review

    "I have collaborated with LE Construction on several project through the years. I highly recommend this builder, they are affordable, they have excellent customer services and do great quality finish work."

Read all reviews on Google

See what fits on your lot

We will check setbacks and how a new room would connect, then give you a realistic budget before you pay for plans.

Get a Free Estimate

Room Additions: FAQs

How big can my room addition be?

That depends on your lot's setbacks, lot coverage limits and any height or floor-area rules in your city or the County, plus association rules if you have one. On many tract lots, there is room for a bedroom or family room at the back. We check the numbers for your property before design starts.

Can my existing heating and cooling handle a new room?

Sometimes. If the system has spare capacity and ducts can reach the room, extending it is the simplest option. If not, a separate ductless system for the addition is common. California's energy code applies to additions, so we account for insulation, windows and equipment in the design.

Will the addition match my house from the street?

That is the goal. We match roof pitch, eave depth, stucco or siding texture, window style and trim. Stucco texture and color are tested on small areas first. A well-matched addition looks like part of the original house.

Do I need an architect for a room addition?

An addition needs plans that show the layout, structure and energy compliance, plus structural engineering. A residential designer or architect usually draws them. We can recommend people to work with and stay involved during design so the plans are buildable and priced.

Related services

Home Additions near you

Related pages

Call NowFree Estimate