

Our detached structures range from basic storage sheds to multi-bay garages with room for ATVs, snowmobiles, and full-size vehicles. Need a garden shed? We’ll match your home’s style and add venting, shelving, or even windows. Want a full-scale garage with electric, insulation, and loft space? We’ll design it to fit your lot and your lifestyle. Every structure is engineered for snow load and built to meet or exceed Montana’s building codes.
We don’t build kits we build real, framed structures with long-term performance in mind. Whether it’s a backyard garden shed, a firewood shelter, or a multi-car garage with workshop space, every building starts with proper planning and solid materials. Our Montana-built garages and sheds include options for slab or pier foundations, ventilation, custom doors, and energy-smart finishes.
Framed, insulated, and built to local code
Snow-rated roofs, vented soffits, and weather-sealed siding
Add-ons like lofts, shelving, or workspace available

We start with a site visit and layout plan making sure your new shed or garage fits your yard, setbacks, and goals. From there, we prep the foundation, frame to spec, install durable siding and roofing, and finish with doors, windows, and trim. You pick the size, style, and materials. We handle the build, the permits, and the final walkthrough.

We design sheds and garages to work with your space not overwhelm it. Need a compact garden shed under 120 sq ft? Done. Want a two-bay garage with an attic loft and workshop? We’ll draft plans to match your needs, zoning, and site layout. Every project includes proper drainage, access planning, and snow-rated structure design. You tell us how you want to use it we’ll build it right.
Montana weather means you need timelines that stick. That’s why we manage every phase of construction in-house or with trusted local partners. From site prep and concrete to framing, siding, and overhead doors, we deliver start-to-finish service with no finger-pointing. You’ll get a dedicated build schedule, clear communication, and one local team responsible for it all.

Custom Floor Plans: You choose the size, doors, roof, and storage layout.
Built for Snow Load: Every structure framed and roofed to handle Montana winters.
Foundation to Finish: We manage concrete, framing, roofing, and trim.
Permit-Ready Plans: We draw and submit all plans to meet local code.
Fit to Match Your Home: Roofing, siding, and colors aligned with your house or cabin.
Don't worry, we can help!
A well-built shed or garage gives you more than just space—it gives you peace of mind. Whether you’re storing tools, winter gear, vehicles, or firewood, our structures keep things safe, dry, and out of your main living space. We build them to handle Montana’s seasons—and to look like they belong on your property.
Add-ons like windows, attic space, or lighting available
Works great for workshops, toy storage, or garden tools
Blends with existing home style and scale
We build every shed and garage to suit Montana terrain and elevation. That means deeper footings, frost protection, weather-rated siding, and snow-shedding roofs. Whether your property is in the valley, on a slope, or exposed to high winds, we engineer each outbuilding for performance, access, and longevity. It’s not just a box it’s a structure designed for your land.
Here are answers to the most common questions we get about detached garages and outbuildings across Montana:
Most of the time, yes especially for anything over 200 sq ft or with utilities. We handle the entire permitting process.
Absolutely. We match materials, colors, pitch, and trim for a seamless look.
We offer slab, pier, or compacted gravel depending on structure size and use.
Most sheds are done in 1–2 weeks. Garages can take 3–6 weeks depending on size and weather.

We design and build custom decks tailored to your home, lifestyle, and outdoor space—built for comfort, code, and long-term value.

Durable, low-maintenance decking in brands like Trex and TimberTech. We install with expert framing and clean finishes.

Traditional wood decks built from cedar or pressure-treated lumber, sealed for longevity and built with care.

We replace rotted joists, tighten loose rails, and restore sagging stairs—bringing your deck back to safe, usable shape.

We clean, sand, and seal old decks to restore natural color and extend the life of your outdoor space.

Tiered decks add dimension and function. We build secure, attractive multi-level systems with unified stairs and rails.

We extend existing decks or replace worn boards with modern composite or sealed wood—saving the foundation when possible.

From pergola-style shade to full patio roofs, we protect your deck space from rain, sun, and snow with stylish coverage.

Enjoy fresh air without the bugs. We build screened rooms and glass-walled sunrooms for relaxing in all weather.

We build grilling areas, outdoor sinks, and kitchen setups into decks—complete with fire-safe materials and smart layout.

Add architectural charm and functional shade with custom pergolas, gazebos, or arbors—built freestanding or integrated.

Slip-resistant, water-safe decks designed to wrap hot tubs or pool edges with beauty and durability.

We construct code-compliant outbuildings including garages, workshops, and storage sheds with matching exterior finishes.

We fabricate and install deck railings and stairs to match your design goals and meet local safety codes.

From rooftop lounges to restaurant patios, we build commercial-grade decks that handle heavy use and meet ADA compliance.

Innovation
Fresh, creative solutions.

Integrity
Honesty and transparency.

Excellence
Top-notch services.
Whether you're looking to add a sun-soaked patio, rebuild a storm-damaged deck, or design a multi-level masterpiece, we’re ready to help. Alliance Deck Builders of Montana brings expertise, materials, and trust to every job no matter the size. Contact us today to schedule your free consultation and let’s bring your outdoor vision to life.

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