Custom Home Additions & Room Expansions in Houston, TX
Primary master suites, 2nd story expansions, detached in-law suites/ADUs, and sunrooms engineered for Houston soils.
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Custom Home Additions & Room Expansions in Houston, TX
Love your neighborhood but outgrowing your current floor plan? A custom home addition in Houston, TX allows you to expand your living space, increase your property value, and stay in the community you love without the hassle and cost of moving. Coast Design & Build provides full architectural design, structural engineering, foundation work, and construction for ground-up room additions and second-story expansions.
Primary Master Bedroom Suites
Expansive master retreats featuring luxury walk-in dressing rooms, spa bathrooms, private outdoor patios, and morning coffee bars.
In-Law Suites & Guest ADUs
Attached or detached accessory dwelling units designed for multi-generational families, guests, or independent living with full amenities.
Second-Story Vertical Additions
Double your living space without shrinking your yard. Engineered with reinforced foundation tie-ins to satisfy Houston wind-load standards.
Our Latest Home Addition Projects
Explore recent primary suites, second-story vertical expansions, and detached ADUs engineered and built across Greater Houston.
Katy, TXKaty Primary Suite & 2nd Story Expansion
Engineered second-story addition featuring a primary master retreat, walk-in dressing room, ensuite spa bath, and reinforced foundation tie-in piers.
Memorial, HoustonMemorial Architectural Sunroom & Suite Expansion
Ground-floor architectural room expansion and light-filled sunroom engineered to strict City of Houston building codes.
Houston HeightsHeights Multi-Gen Guest Casita (ADU)
Detached luxury guest casita / in-law suite featuring full kitchenette, curbless accessible bathroom, private entry patio, and dedicated HVAC.
Bellaire, TXBellaire Ground-Up Structural Addition
Custom room addition featuring bell-bottom concrete pier foundation engineering and seamless exterior architectural integration.
What’s Included in Every Home Additions Project
Complete peace of mind from a coordinated design-build general contracting team.
3D CAD Architectural Visualization
Contingent upon a signed contract, our design team provides full 3D photorealistic renderings and layout plans so you can approve your finished space before construction begins.
Transparent Line-Item Proposal
Detailed fixed-price contract with an agreed scope of work, documented allowances, and milestone schedules.
Comprehensive Workmanship Warranty
Rigorous punch-list inspection and post-completion warranty terms documented in the project contract.
Home Additions in Your Neighborhood
Explore our local remodeling projects and architectural work in your community:
Questions About Home Additions
Clear answers from our design-build general contracting team.
We design and build primary master bedroom suites, second-story additions, kitchen and family room bump-outs, detached or attached guest suites (ADUs), home offices, and sunrooms.
Building out (ground-level addition) is generally more cost-effective if you have sufficient lot space. Building up (second-story addition) requires foundation and first-floor structural reinforcement to handle Houston soil and wind load standards.
Houston's expansive clay soil requires proper foundation engineering, soil testing, and concrete pier/slab-on-grade tie-ins to prevent settling and ensure lifelong stability. We follow strict Houston engineering codes.
Request Your Home Additions Consultation
Schedule a no-obligation in-home consultation and custom 3D design review across Greater Houston.