Updated 10/09/2026
The seven most common home additions are a garage conversion, a bump-out, a room addition, an attic conversion, a second story addition, an attached in-law suite, and a detached casita or guest house. A garage or attic conversion is usually the least expensive way to add living space because it uses space you already have under a roof. A second story addition usually costs the most but adds the most square footage without using any yard.
Master Remodelers is a family-owned home addition and remodeling company that has served Houston, Pearland, Friendswood, League City, Clear Lake and Galveston since 1998. If you love your neighborhood and your kids’ schools but need more room, adding on is often simpler than selling, buying and moving. Here’s how the seven options compare.
Table of Contents
The 7 Home Additions at a Glance
Addition | Space added | Relative cost | Best for |
|---|---|---|---|
Garage conversion | One or two rooms | $ | Game room, office, gym, in-law suite |
Bump-out | A few feet onto one room | $ | A bigger kitchen, bathroom or closet |
Attic conversion | One or two rooms | $$ | Bedroom, office or playroom upstairs |
Room addition | One or more rooms | $$$ | Family room, primary suite, bigger kitchen |
In-law suite | Bedroom, bath and sitting area | $$$ | An aging parent or adult child |
Casita or guest house | A separate small home | $$$$ | Guests, a parent, a home office or a pool house |
Second story addition | A full new floor | $$$$ | Several bedrooms on a small lot |
1. Garage Conversion
What it is: turning an attached garage into finished, air-conditioned living space. We insulate the walls and ceiling, raise and finish the floor, add electrical and cooling, and replace the garage door with a wall, windows or an entry door.
Why homeowners choose it: the slab, walls and roof already exist, so a garage conversion usually costs less and takes less time than building new. In Houston, a ductless mini-split is often the simplest way to cool the space.
Things to know: you lose covered parking, and some HOAs and deed restrictions require a garage-door look from the street or a set number of parking spaces. We check those rules before design.
2. Bump-Out Addition
What it is: a small addition that pushes one wall out a few feet to enlarge a single room.
Why homeowners choose it: a bump-out can make room for a kitchen island, a walk-in shower, a breakfast nook or a bigger closet without the cost of a full addition.
Things to know: it is still new construction, so it needs a foundation, a roof tie-in and a permit.
3. Attic Conversion
What it is: finishing an attic into a bedroom, office or playroom.
Why homeowners choose it: it adds rooms inside the house you already have, with no change to your footprint or yard.
Things to know: not every attic qualifies. It needs enough headroom, floor joists that can carry living space (or can be reinforced), and room for a permanent staircase. In Texas, an attic gets very hot, so it needs good insulation and its own cooling zone. Dormers or skylights add light and headroom.
4. Room Addition
What it is: a new room or wing built onto the side or back of the house, with its own foundation, walls and roof.
Why homeowners choose it: a room addition gives you the most freedom in layout. Common uses are a family room, a larger kitchen and dining area, a home office, or a new primary suite.
Things to know: it uses yard space and must fit within your lot’s setback and lot coverage rules. A good addition matches the existing brick or siding, roof pitch and windows so it looks original to the house.
5. In-Law Suite
What it is: an attached suite with a bedroom, full bathroom, sitting area and sometimes a kitchenette and private entrance, built for an aging parent, adult child or long-term guest.
Why homeowners choose it: both households get privacy while staying under one roof. Most in-law suites are built on one level with a curbless shower, wider doorways and grab bars, so a parent can age in place.
Things to know: some cities and deed restrictions limit a second full kitchen or a separate entrance. Read our full guide to second master and in-law suite additions.
6. Casita, Guest House or Pool House
What it is: a small, separate building on your lot. Depending on the plan, it can be a guest house with a bedroom and bathroom, a pool house, a home office or studio, or a full accessory dwelling unit (ADU) with its own kitchen.
Why homeowners choose it: it offers the most privacy of any addition, and it can serve guests, a parent, a home business or, where allowed, a long-term tenant.
Things to know: a detached unit needs its own foundation, utilities and permits, and many deed restrictions and HOAs regulate whether a second dwelling is allowed and how it can be used.
7. Second Story Addition
What it is: removing all or part of the roof and building a new floor on top of the house.
Why homeowners choose it: it can add several bedrooms and bathrooms without giving up any yard, which makes it a strong option on smaller lots inside the Loop and in established neighborhoods.
Things to know: it is the most involved addition. A structural engineer must confirm that the foundation and walls can carry the new floor, the family may need to move out during part of the work, and the house needs room for a new staircase.
How to Choose the Right Addition
Ask four questions:
- Who is the space for, and for how long? A parent who may need a walker later needs single-level space. Teens may be happy upstairs.
- What space do you already have? An unused garage or a tall attic is usually the least expensive starting point.
- How much yard can you give up? If the answer is none, look at a garage, attic or second story addition.
- What do your deed restrictions, HOA and city allow? The City of Houston has no zoning ordinance, but deed restrictions often control additions. Pearland, Friendswood and League City have zoning, setback and lot coverage rules.
Should You Add On or Move?
Adding on lets you stay in your neighborhood and school district and avoid real estate commissions, moving costs and a higher mortgage rate on a new loan. Moving can make more sense if your lot or deed restrictions won’t allow the space you need, or if the addition would cost more than the neighborhood can support at resale. A free consultation can tell you which side of that line you’re on.
Our Home Addition Process
- Free consultation. We visit, measure and talk through how you’ll use the space and what you want to spend.
- Design and engineering. Drawings, and a structural engineer where the project needs one.
- Written estimate. An itemized estimate covering materials, labor and timeline.
- HOA approval and permits. We prepare the HOA submittal and pull the permits.
- Construction and inspections.
- Final walkthrough.
Master Remodelers also offers home improvement financing, including 0% options for qualified buyers.
Why Houston Families Choose Master Remodelers
- Family-owned and led by President Donald “Don” Borden.
- 35+ years of experience remodeling Houston-area homes.
- Licensed, bonded, and insured, A+ BBB rating, and 2025 and 2026 Pulse of the City Award winner.
- One team for design and build, so you have one point of contact for the whole job.
- Financing for every credit situation.
Frequently Asked Questions
A garage conversion or attic conversion is usually the cheapest way to add square footage, because the foundation, walls and roof already exist. A bump-out is the least expensive way to enlarge a single room.
A bump-out extends one existing room by a few feet, while a room addition creates one or more new rooms with their own foundation, walls and roof. A bump-out costs less but adds less space.
The cost depends on the type of addition, its size, the plumbing it needs and the finishes. Garage and attic conversions are usually the least expensive, and second story additions are usually the most. Master Remodelers provides a free, itemized estimate.
Yes. Every home addition and garage conversion needs a building permit, plus electrical, plumbing and mechanical permits where that work is included. Many neighborhoods also require HOA approval. Master Remodelers pulls the permits and schedules the inspections.
Many can, but a structural engineer has to confirm it. The engineer checks whether the foundation and walls can carry the new floor and recommends any reinforcement before design is finalized.
Adding on is usually better if you like your neighborhood and schools, your lot and deed restrictions allow the space you need, and the finished home won’t be priced far above others nearby. Moving can make more sense when the lot or restrictions won’t allow the space.
Find the Right Addition for Your Home
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