Osburn Horizon Wood Fireplace with Prairie Style Faceplate and Refractory Brick Panels

Built-in wood fireplaces are factory built and tested units designed for new construction, remodels, or additions. If you’re upgrading an existing masonry wood fireplace, you may actually need a wood insert instead.

Built-In Wood Fireplaces

• Designed to be framed into a wall or chase
• Require a complete, model-specific chimney system (double or triple-wall metal pipe) 
• Open-hearth models provide the classic ambiance of a traditional wood fire, while EPA-certified fireplaces deliver higher efficiency and greater heat output.

Confirming the Right Fit

• Review required framing dimensions and combustible clearances in the manual
• Most installations allow standard wood framing as long as clearances are followed
• Not sure if this model fits your project? Our NFI-Certified team can quickly verify compatibility and recommend the correct components

A properly designed chimney system is essential for safety, code compliance, and consistent performance. Wood fireplaces rely on natural draft, which makes chimney design especially important — height, location, and the components used all impact how well the fireplace burns and how easily it starts.

Certified Chimney System

• Must use the listed and approved chimney pipe for that specific fireplace
• Some manufacturers require their own branded components; others approve compatible systems such as DuraVent
• Mixing pipe brands or series is unsafe and will void the warranty
• A complete chimney system typically includes: pipe sections, firestops, attic insulation shield, roof flashing, storm collar, and chimney cap

Chimney Height 

• Wood fireplaces must follow the 3-2-10 rule: the chimney termination needs to extend at least 3 ft above the roof and be 2 ft higher than anything within 10 ft
• Each fireplace also has a minimum chimney height requirement, regardless of the home’s roofline or overall height

Chimney Location

• Home layout can affect draft — the stack effect (warm air rising inside the home) can create negative pressure on lower levels, making the fireplace harder to light or more prone to smoke spillage
• Wind patterns, rooflines, and nearby trees or structures can also influence airflow and impact how well the chimney drafts

Building codes for wood fireplaces vary widely by state, county, and even city, and they can affect everything from chimney height to required components and installation methods. Some jurisdictions mandate specific chimney systems, outside air kits, inspections, or additional clearances beyond the manufacturer’s instructions. Because each authority interprets the code differently, it’s important to verify the requirements for your location. When in doubt, check with your local authority having jurisdiction (AHJ) or reach out to us and we can help point you in the right direction.

Choosing the right wood fireplace is only the first step — the chimney system is what makes the installation safe, code-compliant, and reliable for years to come. Ordering everything together ensures all components are compatible and arrive at the same time.

Typical Chimney Packages Include

• Chimney pipe sections in various lengths
• Elbows for navigating around framing or structural obstacles (30° maximum per offset)
• Firestops when passing through upper floors or between stories
• Roof flashing and storm collar to seal the roof penetration and prevent water intrusion
• Chimney termination cap to protect the system and ensure proper draft

Outside Air Kit

• Required or strongly recommended on many fireplaces
• Provides dedicated combustion air for better draft
• Especially important in newer or tightly sealed homes

Floor Protection

• Most wood fireplaces require a hearth extension in front of the opening
• Protects the floor from hot embers or logs that may fall forward

Blower Fan

• Available on select models and a simple way to increase comfort
• Helps circulate warm air from the firebox back into the room

Glass Doors

• Available on many open-hearth wood fireplaces
• Must be used fully open or fully closed during operation
• Provide a more finished, custom look

Chase Cover

• Used when the chimney pipe is enclosed in an exterior chase
• Provides a clean, finished look and protects the chimney system
• Seals the top of the chase and keeps water, snow, and debris out

Vented Gas Logs

• Many wood fireplaces can also accept a vented gas log set as an alternative fuel option
• Provides the look of a natural wood fire with the convenience of gas
• Must be paired with a working chimney system, just like burning real wood

We can map out the chimney system specific to both your home and the fireplace you’ve chosen. Request our planning sheet for a quick overview of the variables to consider, then send us a sketch or a few photos — we’ll take it from there.

Why Reach Out?

• Ensure all components are correct the first time
• Avoid costly installation delays or last-minute parts
• Have everything ship together, reducing damage risk and simplifying delivery
• Prevent accidentally ordering incompatible chimney parts

Our NFI-Certified team is ready to help. Call, chat, or email us today!