Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
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AfterFast, Reliable Home Additions & ADU Across Bloomington
A home addition or ADU in Bloomington, CA typically runs $45,000 to $220,000 depending on scope, and most families we work with in the 92316 ZIP code need both design and county-level permitting handled from day one. You’re not calling a call center. You’re calling Tom Barrett’s sons and their crews, who know that Bloomington parcels answer to San Bernardino County Building and Safety, not a local city hall. If you’re thinking about a room addition, a detached ADU, or a garage conversion, call (877) 610-1318 and we’ll walk the property, talk through what the county will actually require, and give you a written scope with real allowances before anyone swings a hammer.
The homes here were mostly built between the late 1940s and the 1970s. That means post-and-beam framing, aging stucco, original slab foundations, and wiring that sometimes predates your grandparents’ refrigerator. Opening up a Bloomington wall for an addition or ADU tie-in isn’t a weekend puzzle. It’s a county-permitted job that rewards patience, paperwork, and a contractor who’s done it here before. We have.
Why Barrett & Sons Construction Is Bloomington’s Preferred Home Additions & ADU Company
Tom Barrett founded Barrett & Sons Construction in 1998, and the name on the truck is the name on the license. His sons run the crews, and we publish Tom’s name, address, and license number so you can look it up before signing anything. That matters in Bloomington, where homeowners have dealt with out-of-area contractors who assume city permits, file with the wrong jurisdiction, and stall the county inspection calendar for weeks. We don’t guess. We file with San Bernardino County the first time.
Every Bloomington job follows the same structure: written scope, written allowances, written change orders. The permit inspector works for you, not for us, and we like it that way. When a Bloomington homeowner asks us to open up a 1960s stucco wall and tie in a new detached ADU, we know the county inspector will want to see what’s behind that lath. So do we. That’s why our contracts include inspection-first language and time-and-materials allowances for the surprises older homes hide.
Reviews from Bloomington customers tend to mention the same things: the live person answering the phone at (877) 610-1318, the crew showing up in Barrett & Sons uniforms, and the written change order that arrived before any scope changed. We’re not a franchise dispatching strangers. We’re an owner-operated crew that has worked Bloomington’s mid-century homes long enough to know which ones still carry original knob-and-tube and which slabs are going to need deeper footings.
Our Home Additions & ADU Services in Bloomington
Here’s what we handle most often for homeowners across Bloomington. Each project starts with a free estimate and a written scope. No allowances that aren’t on paper.
ADU Design & Permitting
An ADU in Bloomington isn’t just a set of plans. It’s a county submittal that has to account for San Bernardino County Building and Safety requirements, and increasingly for rezoning pressure as logistics and warehouse developers push industrial projects into historically residential parcels. We prepare the drawing set, file the county permit, and manage the inspection schedule. When the inspector red-tags something, we fix it and get the reinspection scheduled. That’s the job.
New Detached ADU
A new detached ADU on a Bloomington lot usually runs $90,000 to $220,000. On oversized semi-rural lots that once held citrus or poultry, we often site the unit to preserve driveway access and rear-yard privacy. The expansive clay soil here means we don’t pour a detached ADU slab without a soil report and pre-pour saturation. Skip that and the slab moves within two wet-dry cycles. We don’t skip it.
Garage Conversion ADU
Converting a 1950s or 1960s garage in Bloomington runs $30,000 to $80,000. These garages were rarely built to living-space code. We typically find undersized footings, no vapor barrier, and a roofline that won’t meet current insulation requirements. The county will require upgrades once walls are open, and our written allowance process covers exactly that. You’ll know what the rewire, the footing upgrade, and the shear wall will cost before we start, not after.
Junior ADU & Interior Conversion
A junior ADU carved out of an existing Bloomington home can run $45,000 to $130,000 when it involves bedroom conversion, a kitchenette, and a separate entrance. We handle the egress, the fire separation, and the sound attenuation the county wants. If the home still has original stucco and single-pane windows, we’ll also talk honestly about whether those need to be addressed as part of the scope.
Room Additions
Room additions in Bloomington start around $45,000 and climb with square footage and foundation complexity. Adding over an old slab without a soil report is the most common mistake we correct from other contractors. The clay and silty loam across Bloomington’s flatlands heaves and shrinks dramatically between wet winters and dry summers. We use deeper continuous footings and pre-pour soil saturation as standard practice. Ask anyone on your street whose addition cracked within two years. Then ask how their contractor handled the footing depth.
What happens when you call
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A real person answersNo phone trees - you reach a local pro.
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You get an upfront price rangeHonest numbers before anyone is dispatched.
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A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
Trusted Brands We Service in Bloomington
When an addition or ADU calls for tile work, shower systems, or roofing tie-ins, we install brands you can look up. We work with Schluter waterproofing systems in ADU bathrooms and kitchenettes, and we’ve used Grohe fixtures across several Bloomington additions and conversions. These aren’t mystery materials off a van. They’re names you can verify, backed by our 90-Day Done Right Promise. If something isn’t right, Tom comes back and makes it right.
Common Home Additions & ADU Problems We See in Bloomington Homes
- Wrong jurisdiction filings. A contractor assumes Bloomington has local city permits and files with the wrong office. The county inspection calendar stalls for weeks, and the homeowner is left holding an unpermitted addition.
- Slab cracking from expansive soil. Bloomington’s clay and silty loam heaves in winter and shrinks in summer. Add a room over an old slab without a soil report and deeper footings, and the new floor cracks within a couple of wet-dry cycles.
- Knob-and-tube discoveries behind stucco walls. Mid-century homes in the 92316 flatlands still carry original wiring. Open an exterior wall to tie in an ADU and the county inspector will require the exposed branch circuits to be addressed. That’s a code upgrade, not an optional extra.
- Santa Ana heat shrinking the build window. Summer temps hit 108 to 112°F and drying winds shorten workable time for concrete pours, exterior coatings, and adhesives. We schedule pours early and adjust mixes for the heat. Out-of-town crews sometimes pour at noon and wonder why the slab checks.
Pricing for Home Additions & ADU in Bloomington, CA
| Project Type | Bloomington Price Range |
|---|---|
| Home Addition | $45,000 - $130,000 |
| ADU Construction | $90,000 - $220,000 |
| Garage Conversion ADU | $30,000 - $80,000 |
What moves the price? Foundation depth on expansive clay, the wiring and panel upgrades a county inspector tags once walls are open, roof tie-in complexity on mid-century framing, and interior finish level. Every scope we write includes allowances in writing, and every price change arrives as a written change order before work proceeds. Call (877) 610-1318 for a free estimate and a line-item scope you can hold us to.
We Also Serve Cities Near Bloomington
Our crews work Home Additions & ADU in Bloomington and the surrounding Inland Empire communities. If you’re in Fontana, Rialto, Glen Avon, or Pedley, we bring the same written-scope process and the same county permitting discipline. Scheduling and dispatch are coordinated from our Inland Empire office, and our crews live and work throughout this corridor.
Serving Bloomington, CA - Our Local Coverage Area
We’re based in the Bloomington area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs - Home Additions & ADU in Bloomington
What extra code upgrades does a Bloomington ADU trigger when the county inspector sees the opened walls?
A Bloomington ADU tie-in that opens an exterior wall on a mid-century home typically triggers smoke and CO2 detector retrofits, AFCI circuit protection on exposed branch wiring, and sometimes shear-wall or footing upgrades once the inspector sees what the original construction looks like. The county field inspector works for you, not for us, and if the wall hides knob-and-tube or undersized framing, the inspector will note it on the rough-in card. We write a time-and-materials allowance into the contract so that upgrade is a known line item, not a surprise invoice. Call (877) 610-1318 and we’ll explain exactly what we’d expect on your home.
Why do Bloomington slabs crack more than coastal LA homes, and how does that affect a room addition?
Bloomington sits on expansive clay and silty loam that heaves in wet winters and shrinks during dry summers, while coastal LA builds on sandier, better-drained soil. That movement stresses older slabs and the original footings poured in the 1950s and 1960s. A room addition on that soil needs a soil report, deeper continuous footings, and pre-pour saturation before any concrete goes down. We make that standard practice here. It’s also why we never skip the county soil review on an addition permit.
How do the Santa Ana winds and 108°F summers shorten the build window for a Bloomington ADU?
Summer temperatures in Bloomington regularly hit 108 to 112°F, and Santa Ana wind events dry out concrete and exterior coatings far faster than the product specs allow. That shortens the viable window for slab pours, stucco patches, and roofing adhesives to early mornings and select days. We adjust mix designs for heat, schedule pours before 9 a.m., and keep spray-down curing going through the first 48 hours. An out-of-town crew that pours at noon in August will get checking and cracking, and the county inspector will see it.
Do I need both residential and heavy commercial permits for a garage conversion ADU in Bloomington?
Sometimes, yes, because Bloomington is unincorporated and governed by San Bernardino County, and the rezoning pressure from logistics and warehouse developers means some historically residential parcels now carry mixed-use or commercial overlay designations. A garage conversion ADU on a 92316 parcel can require a dual-scope permit set that addresses both residential remodel code and heavy commercial setback requirements under county review. We file the correct set the first time. Guessing wrong stalls your inspection calendar for weeks.
If my Bloomington home was built in the 1950s, will an ADU addition require a whole-house rewire?
Not necessarily. A Bloomington ADU addition usually requires upgrading only the branch circuits that are exposed by the work and whatever the county inspector flags on the rough-in. If we open a wall and find original knob-and-tube still feeding the circuit, that branch gets rewired and brought to current code, but we won’t invent a whole-house rewire you don’t need. The rewire scope goes in the contract as a written allowance before the wall comes open, so you approve the number in writing, not after the fact.
Get a Written Estimate for Your Bloomington Home Addition or ADU
If you’re planning a room addition, a detached ADU, or a garage conversion in Bloomington, call (877) 610-1318. We’ll schedule a walkthrough, talk through what San Bernardino County will require, and hand you a written scope with real allowances and real line items. Every price change comes in writing before work proceeds. Every job is backed by our 90-Day Done Right Promise. Tom’s name, address, and license number are published for you to verify. Ask anyone on your street, or look up the license yourself.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving Bloomington and the Inland Empire since 1998.