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Additions & ADU’s

Smart, Seamless Additions and ADUs Tailored to Fit Your Life

Additions & ADUs | Custom Expansions & Designs

Create the space you need without the stress. Abstract Residential Design+Build plans, designs, and builds high-end additions and ADUs with a true design-build process that aligns drawings, selections, budget, and schedule before construction begins. With in-house architectural design, disciplined pre-construction planning, and 22 years of construction experience, you get a predictable path and a finished space that feels seamless with your home.

Schedule a Discovery Call
Request a Pre-Construction Planning Consult

The Problems We Solve (Before They Derail a Project)

Additions and ADUs fail when scopes are vague, selections are late, or permitting surprises the team. We remove those risks up front.

  • Budget creep from incomplete scopes to replaced with a line-item budget
  • Decision fatigue- guided selections roadmap with clear deadlines
  • Permitting/lot coverage/height limits- early feasibility and code checks
  • Structural and utility conflicts- coordinated drawings before mobilization
  • Dust, noise, and site safety- a written habitation plan if you will live on site
About Us

Why Abstract: One Accountable Team

You work with a single, integrated team from first sketch to final walkthrough.

  • In-house architectural design coordinated with interiors, engineering, and construction

  • 22 years of construction experience informing practical detailing and sequencing

  • Weekly owner meetings with agendas, decisions, and next steps documented

  • Planned site walks (electrical, plumbing, cabinetry) before close-up

  • Third-party Maverick warranty registered at closeout and transferable

Integration is how we reduce change orders, shorten decision cycles, and keep momentum.

The Abstract Plan (3 Clear Steps)

1) Discover

 We listen first: goals, budget, how you live today, and how the new space should perform.

2) Define (Pre-Construction Agreement)

We lead a structured design and pricing effort with drawings, engineering, selections, vendor quotes, and a buildable schedule, so the numbers are real and the path is clear.

3) Deliver

We build with weekly updates, proactive site walks, dust and safety controls, and disciplined cost management. Final walkthrough and punch are documented, followed by warranty registration.

4) Permit & Pricing Package

You receive a pricing-ready set for competitive bids and permit submission coordinated drawings, outline specs, finish schedules, and a documented scope ready for a fixed-price or open-book contract.

Start with a 30-Minute Discovery Cal

The Pre-Construction Advantage (Where Risk Is Removed)

Before we mobilize, you receive a complete plan tailored to additions and ADUs:

  • Pricing-ready drawings prepared for permitting and competitive bids
  • Selections roadmap with due dates to prevent last-minute scrambling
  • Line-item budget with allowances and contingencies clearly defined
  • Locked-in subcontractor pricing through detailed scopes of work
  • Procurement strategy (we pre-purchase and store long-lead items when appropriate)
  • Integrated build schedule aligned with inspections, utilities, and lead times
  • Habitation plan for dust control, safety zones, temporary walls, and access if you’ll occupy the home

Front-loaded clarity means fewer surprises, faster decisions, and a smoother build.

About Us

Transparent Contract Options

Different projects call for different commercial terms. We offer Fixed-Price and Cost-Plus (open-book) agreements and guide you to the model that best fits your scope and risk profile.

Fixed‑Price

Best when drawings and selections are fully defined. Predictable total cost and clear inclusions.

Cost-Plus (Open-Book)

Best for longer or evolving scopes and when markets may shift. You see every invoice and pay actual costs, avoiding padding for unknowns.

What’s at Stake (and What’s Possible)

Choosing the wrong partner can lead to unfinished work, budget overruns, and disputes. The most expensive project is the one that doesn’t finish.

With the right plan and team, you get:

  • Space that truly solves your daily needs
  • A predictable budget and schedule
  • A clean, safe, and respectful jobsite
  • A seamless integration that adds lasting value
Our Services

Abstract Residential Design+Build plans, designs, and constructs additions and ADUs with integrated architectural design, rigorous pre-construction, and transparent project management that keep budgets and schedules on track across Boise, Eagle, McCall, Garden Valley, and the greater Treasure Valley.

Ready to Plan Your
Addition or ADU?

Build with clarity, control, and a team that finishes.

Schedule a Discovery Call
Request a Pre-Construction Planning Consult