Home Addition FAQs Answered By A Licensed Contractor
These home addition FAQs answer what homeowners ask us most — space limits, costs, permits, timelines and living at home during the work. Answered by H&A My Design, a licensed California general contractor (CSLB #999603), family-owned for more than 20 years. Serving Southern California and the surrounding areas.
Ask us anything — the first conversation and the on-site consultation are free.
Home Addition FAQs Grouped By What You Need To Know
We have grouped these home addition FAQs into four areas: planning and limits, cost and value, permits and timelines, and construction and daily life. Where the honest answer is “it depends”, we explain exactly what it depends on.
Why Honest Uncertainty Beats False Precision
A contractor who quotes a confident price or schedule before seeing your house is guessing. That guess gets corrected later — usually upward, usually after you have committed. We would rather explain the variables now.
What A Good Answer Looks Like
It names the factors, explains which apply to your house and tells you what needs to happen to narrow the range.
Questions Worth Asking Any Contractor
Whoever you hire, these questions separate a professional operation from an optimistic one.
- What is your licence number, and can I verify it?
- Who prepares the drawings and files the permit?
- What is included, what is an allowance, and what is excluded?
- How are changes priced and approved?
- Who runs the site day to day?
Home Addition FAQs: Planning And Limits
How much can I add to my house?
It depends on your lot size, setbacks, height limits, lot coverage and any floor-area rules in your city. We confirm the realistic maximum for your property during the consultation.
Should I build out or build up?
Building out usually costs less per square foot but uses yard; building up keeps the yard but needs structural work and a stair. See home expansion planning for how we compare them.
Can my house support a second storey?
Many can with some reinforcement. Structural engineering confirms what is needed before design is finalised. See second-story additions.
Do floor-area rules apply in Los Angeles?
Yes. Single-family zones in the City of Los Angeles carry floor-area limits published by Los Angeles City Planning. Other cities apply their own rules.
Is an addition or an ADU better for me?
Family living usually suits an addition; independence or rental income often suits an ADU. We compare both for your lot.
Home Addition FAQs: Cost And Value
How much does a home addition cost?
It depends on size, whether you build out or up, the condition of the existing house, plumbing and finish level. We give a realistic range after the consultation and a detailed proposal once the scope is set.
Why will you not quote a price per square foot?
Because foundations, structural work, plumbing and finishes drive cost more than floor area. A per-square-foot figure would mislead you.
Which kind of addition costs the most?
Rooms with plumbing — kitchens and bathrooms — and second storeys with structural reinforcement usually cost the most per square foot.
Are engineering and permit fees included?
Your proposal states clearly what is included and what is paid directly, so nothing is hidden.
Does an addition add value?
A permitted, well-built addition adds usable space and broadens the appeal of the house. Unpermitted work can become a liability, which is why every addition we build goes through plan check and inspection.
Home Addition FAQs: Permits And Timelines
Who handles the permits?
We do, as part of the contract. See addition design and permits.
How long does permitting take?
It varies by city. In our experience review typically takes about 6 to 14 weeks. Houses in the City of Los Angeles are reviewed by LADBS.
How long does construction take?
As a guide, major additions typically take five to eight months of construction, depending on size, terrain and finish package.
Can work start before the permit is issued?
No structural work can begin without an issued permit. We plan the schedule around issuance.
What if my house has unpermitted past work?
We identify it during the survey and explain the options before the permit is submitted.
Home Addition FAQs: Construction And Daily Life
Can we live at home during construction?
Usually yes. We build and weather in the addition before opening into the house. Some second-story stages may call for a short move-out, and we tell you early.
How do you control dust and noise?
Sealed barriers, floor protection and permitted working hours. The site is cleaned and secured at the end of every day.
Will the addition match my house?
That is the goal from the start. Rooflines, siding, windows, trim and flooring are matched so the new space looks original.
Are you licensed and insured?
Yes. H&A My Design is a licensed California general contractor, CSLB #999603, and carries bonding and insurance.
Which areas do you serve?
We build home additions throughout Los Angeles, the San Fernando Valley, Sherman Oaks, Encino, Tarzana, Woodland Hills, Calabasas, Westlake, Pasadena, Glendale, Culver City, the South Bay, Santa Clarita Valley, Ventura County, Thousand Oaks, Beverly Hills, West Hollywood, Santa Monica, Malibu, Agoura Hills, Simi Valley, Burbank, Granada Hills, Canoga Park, Reseda and the surrounding areas.
Home Addition FAQs: The Terms People Ask Us To Explain
Many home addition FAQs are really vocabulary questions. Here are the terms that come up most, explained without jargon.
Setback And Lot Coverage
A setback is the minimum distance a building must sit from a property line. Lot coverage is the share of the lot that buildings may cover. Together they decide where ground-level additions can go.
Floor-Area Ratio
The total floor area allowed relative to the size of the lot. It caps how much you can add, whether you build out or up.
Tie-In
Where the new structure joins the existing house — foundations, framing, roof and weatherproofing. It is the most important detail of any addition.
Why It Matters
A well-detailed tie-in is invisible and dry. A poor one shows cracks, leaks and a visible seam for years.
Title 24 And Final Inspection
Title 24 is California’s energy standard, documented with your permit. Final inspection confirms the addition is complete and approved for use.
Real Projects Behind These Answers
Our West Hills full-house renovation and addition, one of the projects these answers come from.
Ask The Addition Question That Is Not Listed
If your question is not among these home addition FAQs, ask it directly. The first conversation and the on-site consultation cost nothing and carry no obligation.
Where To Go Next
Home Addition Construction
How additions are built and inspected.
Homeowner Experiences
Hear directly from Southern California clients who trusted H&A My Design with their custom homes, ADUs, and additions.
Walk the finished home — navy kitchen with brass fittings, an open living space and a new double-vanity bathroom.
“We’re extremely happy with the results. Without a shadow of doubt, we’ve already recommended them to other neighbors.”
“Everybody was phenomenal to work with, a pleasure to have. Totally fair and wonderful company and great family.”
“H&A made the entire process transparent. Having one GC manage blueprints, city permits, and the build was night and day.”
“Their Canoga Park showroom made selecting our cabinets, quartz, and fixtures so easy. Finished right on schedule.”
“Converted our garage into a 2-bedroom rental. Flawless craftsmanship and leased immediately after final inspection.”
See the full before and after — the original kitchen, the opened-up living space and the finished bathrooms.
“From 3D plans to final city sign-off, H&A handled everything. No surprise change orders, no stress.”
“Built a modern ADU for my parents. The accessibility and aesthetic details exceeded all our expectations.”
Serving Southern California
Licensed throughout Los Angeles & Ventura Counties. HQ Showroom at 6723 Variel Ave, Canoga Park, CA.
MORE SPACE.
MORE VALUE.
Design, permits, showroom selections, and master construction—managed by one accountable team.