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Quikrete Home Additions & ADU: The Thousand Oaks Owner’s Guide
If you’re planning a home addition or ADU on a Thousand Oaks property where Quikrete concrete products anchor the foundation, slab, or retaining walls, we can help. Mason Remodeling Co Thousand Oaks handles full home additions and ADU construction in the $45,000 – $130,000 installed range, and we work with Quikrete mixes and concrete products daily. Most homeowners contact us because a previous pour failed, a slab cracked beyond expected settling, or a foundation wasn’t mixed right for Ventura County’s clay-heavy soil. The fix isn’t a parts swap. It’s knowing how the concrete interacts with everything built on top of it.
We’re an independent general contractor in Thousand Oaks, not affiliated with Quikrete. But we’ve poured, patched, and replaced enough Quikrete work to know what holds up here and what doesn’t. If you’re dealing with a failing slab, a cracked stem wall, or an ADU foundation that’s shifting, call us at (805) 309-3386. We’ll tell you what it costs and how long it takes, then we’ll do exactly that.
Which Quikrete Products This Applies To

Quikrete isn’t one product. It’s a family: fast-setting concrete, standard 5000 PSI mix, crack-resistant concrete, mortar mixes, and surface bonding cement. For home additions and ADUs in Thousand Oaks, the products that matter most are the structural ones: Quikrete 5000, Quikrete Crack-Resistant Concrete, and Quikrete FastSet Concrete for footings and repair work. Each behaves differently under load, and the wrong mix in the wrong place shows up within months, not years.
Identification: Check the bag. The PSI rating is printed on the front. 5000 PSI is the minimum you want for load-bearing slabs and stem walls in addition construction. FastSet sets in 20 – 40 minutes and is meant for fence posts, mailboxes, and small pad repairs, not foundation work. Crack-Resistant has polymer fibers mixed in and handles the minor ground movement common in Thousand Oaks neighborhoods like Newbury Park and the Conejo Valley floor. If you’re unsure which product was used originally, a core sample or a chip test tells us fast.
OEM vs aftermarket for Quikrete: Concrete doesn’t have OEM parts the way a dishwasher does, but the mix matters just as much. Quikrete products are engineered and consistent. Generic bagged concrete from a big-box store can have inconsistent aggregate size and variable cement content. For anything structural, we spec Quikrete by name or a commercial ready-mix supplier. For small cosmetic patches and non-load-bearing work, a standard Quikrete mix works fine.
Styles & brands we work with







Signs Your Quikrete Foundation or Slab Is Failing
- Diagonal cracks wider than a hairline at wall corners. This usually means differential settling, where one section of the slab dropped while another held. In Thousand Oaks, clay soil expands when wet and shrinks when dry, and that cycle pulls slabs apart.
- Doors or windows that stick seasonally. The framing hasn’t warped. The slab under one side of the opening moved enough to throw the opening out of square.
- Visible efflorescence (white chalky residue) on stem walls. Water is moving through the concrete and depositing minerals on the surface. It means the mix was porous or the drainage around the addition is wrong.
- Hollow-sounding tapping on a patio or walkway slab. The slab has delaminated from its base. Once that void forms, the concrete will crack under weight it used to carry without thinking.
- Water pooling against the foundation after rain. In Thousand Oaks winters, that pooled water saturates the soil, which swells, which pushes against the foundation. The concrete wasn’t the problem. The drainage detail was.
See the difference
Before
After
Before
After
Before
AfterReplacement Cost & What’s Included

A home addition in Thousand Oaks runs $45,000 – $130,000. ADU construction starts higher: $90,000 – $220,000 when built as a permitted dwelling unit with kitchen, bath, and separate entrance. What drives the range isn’t just square footage. It’s what’s underground: soil compaction, drainage correction, and whether the existing foundation can carry the new load or needs piers and a new stem wall. Those are the conversations we have before we quote, not after.
Every proposal from Mason Remodeling Co Thousand Oaks includes a written price before work starts. That price covers the concrete work, the framing, the tie-in to existing utilities, the permits, and the finish work. No surprise invoices. No verbal estimate that grows on the final bill. If the work isn’t right within 365 days of completion, our 365-Day Done Right Promise means we make it right at no cost to you.
| Project Type | Thousand Oaks Installed Range |
|---|---|
| Home Addition | $45,000 – $130,000 |
| ADU Construction | $90,000 – $220,000 |
| Garage Conversion | $30,000 – $80,000 |
| Foundation Repair (crack, small slab) | $400 – $1,800 |
The cost above includes labor, materials, permits, and disposal. We also stock and install other brands on addition interiors: KraftMaid cabinetry, Cambria and Silestone countertops. If your addition includes a kitchen or bath, those specs get locked into the same written price before we start.
DIY or Call Us?
Here’s the honest split. If you’re patching a hairline crack in a non-structural patio slab, a Quikrete crack sealant and an afternoon is a reasonable DIY job. If you’re asking whether a cracked stem wall under a load-bearing wall can wait, you need a structural assessment, and that’s not a bag-of-mix fix. Concrete work on foundations, footings, and anything holding up habitable space requires permits and inspections in Thousand Oaks. Get the mix wrong, and the failed inspection costs more than the pour.
We’ve seen additions where a homeowner or handyman poured a footing with FastSet because it was cheaper and faster. Within a season, the wall above it cracked, and the fix cost triple what the right mix would have. Don’t be that project. If you’re unsure, call us at (805) 309-3386. We’ll look, tell you what’s actually wrong, and give you a written price. Estimates are free.
FAQs

A properly poured Quikrete 5000 slab on compacted, drained soil lasts 50+ years in this climate. The failure point in Thousand Oaks is rarely the concrete itself. It’s the soil preparation and drainage underneath.
Sometimes. If the crack is non-structural and the slab isn’t carrying load, crack injection and sealing works. If the crack extends through a stem wall or a load path, replacement or piering is the honest fix. Call (805) 309-3386 for an assessment, and we’ll tell you which one applies to your situation.
An ADU takes 6 – 12 months including permits and inspections. A home addition takes 3 – 8 months depending on scope. The city’s plan check and inspection schedule in Thousand Oaks typically adds 4 – 8 weeks to the timeline, and we build that into our schedule from day one.
Yes. We carry Quikrete 5000, Crack-Resistant, and FastSet mixes on our trucks for repair and small pour work. For large pours on additions and ADUs, we order commercial ready-mix to spec with the same structural requirements, so the concrete arrives mixed, tested, and ready to place.
Tell me what you need done. We’ll tell you what it costs and how long it takes, then we’ll do exactly that. Call Mason Remodeling Co Thousand Oaks at (805) 309-3386 for your free estimate on a Quikrete home addition or ADU project. Isaac Pruett and the crew have been serving Thousand Oaks for years, from whole-home additions near Lang Ranch to ADU builds off Lynn Road. A real person answers the phone, every time.
Written by Isaac Pruett, Owner, Mason Remodeling Co – Thousand Oaks, CA at Mason Remodeling Co Thousand Oaks, serving Thousand Oaks and nearby areas.


