How to Install a Wood Burning Insert: A Comprehensive Guide

Installing a wood burning insert is a significant home improvement project that can dramatically improve the efficiency and ambiance of your fireplace. Done correctly, it transforms an existing, often inefficient open fireplace into a powerful heating source. This guide, drawing upon my decades of experience in chimney and fireplace installation, will walk you through the entire process, ensuring a safe and successful installation.

Preparing for Installation

Before you even think about touching a wrench, thorough preparation is key. This stage involves assessment, planning, and gathering the necessary materials.

Assessing Your Fireplace and Chimney

The first and most crucial step is assessing your existing fireplace and chimney. This isn’t just about measuring dimensions; it’s about determining compatibility and safety.

• Fireplace Dimensions: Precisely measure the fireplace opening (height, width, and depth). These measurements are critical for selecting an insert that fits snugly and safely. Ensure the insert’s firebox will fit through the existing opening and that there’s sufficient clearance around the insert once installed.
• Chimney Condition: Inspect the chimney’s interior. Look for cracks, crumbling mortar, or creosote buildup. A compromised chimney can lead to dangerous carbon monoxide leaks or even chimney fires. A professional chimney sweep should be consulted for a thorough inspection and cleaning. Creosote removal is essential before installation.
• Chimney Liner: Most modern codes require a stainless steel chimney liner specifically sized for the insert. This liner extends from the insert’s flue collar all the way to the top of the chimney, providing a dedicated pathway for exhaust and preventing dangerous gases from escaping into your home. Avoid skipping this crucial step for any old chimney.

Selecting the Right Wood Burning Insert

Choosing the right insert is paramount for efficient heating and safety. Consider the following factors:

• Heating Capacity: Calculate the square footage you need to heat. Inserts are rated by their BTU (British Thermal Unit) output, which indicates their heating power. Choose an insert that matches your heating needs, factoring in your home’s insulation levels.
• Insert Dimensions: As mentioned earlier, ensure the insert’s dimensions are compatible with your fireplace opening. Allow for some wiggle room for installation, but avoid selecting an insert that’s significantly smaller than the opening, as this will reduce efficiency.
• EPA Certification: Look for inserts that are EPA-certified. This certification ensures the insert meets stringent emission standards, burning wood more cleanly and efficiently, and reducing pollution.
• Style and Features: Consider the aesthetic appeal of the insert and any desired features, such as blowers (which circulate heated air), thermostats, or catalytic combustors (which further reduce emissions).

Gathering Necessary Tools and Materials

Having the right tools and materials on hand will streamline the installation process. Here’s a checklist:

• Wood Burning Insert: Obviously!
• Stainless Steel Chimney Liner: Of the correct diameter and length, as recommended by the insert manufacturer.
• Chimney Liner Insulation Wrap (Optional): Can improve draft and further reduce creosote buildup.
• Top Plate (Chimney Cap): To seal the chimney opening and prevent water and debris from entering.
• Block-Off Plate: To seal off the area between the fireplace and the chimney, preventing heat loss and drafts.
• High-Temperature Sealant: For sealing connections.
• Measuring Tape, Level, Wrench Set, Screwdrivers, Drill, Hammer, Safety Glasses, Work Gloves.
• Masonry Drill Bits (if needed): For drilling into brick or stone.
• Flashlight or Headlamp: Essential for working inside the chimney.
• Moving Dolly or Appliance Dolly: For moving the heavy insert.
• Helper: This is a two-person job!

Installing the Wood Burning Insert

With your preparations complete, it’s time to install the insert.

Preparing the Fireplace Opening

• Clean the Fireplace: Remove all ashes, debris, and loose mortar from the fireplace opening.
• Prepare the Hearth: Ensure the hearth is level and structurally sound. It needs to be able to support the weight of the insert. If necessary, reinforce the hearth.
• Remove the Damper: The existing fireplace damper should be removed or permanently locked in the open position. This allows for the unimpeded passage of the chimney liner.

Installing the Chimney Liner

This is arguably the most critical step and requires precision.

• Lower the Liner: Carefully lower the stainless steel chimney liner down the chimney, starting from the top. Use ropes or straps to control the descent and prevent damage to the liner. This is where the second person is indispensable.
• Secure the Top Plate: Attach the top plate to the top of the chimney, sealing it to prevent water and debris from entering. Connect the liner to the top plate securely.
• Connect to the Insert: At the bottom, connect the liner to the insert’s flue collar using appropriate connectors and high-temperature sealant. Ensure a tight, airtight seal.

Installing the Wood Burning Insert

• Position the Insert: Carefully move the insert into position in front of the fireplace opening. Use a moving dolly to avoid back strain.
• Slide the Insert In: Slowly and carefully slide the insert into the fireplace opening, ensuring it’s properly aligned with the chimney liner.
• Install the Block-Off Plate: Secure the block-off plate to seal the area around the insert, preventing heat loss and drafts. Use high-temperature sealant to ensure an airtight seal.
• Final Adjustments: Make any necessary adjustments to ensure the insert is level and securely in place.
• Connect Electrical Components (if applicable): If your insert has a blower or other electrical components, connect them to a dedicated electrical circuit according to the manufacturer’s instructions.

Final Inspection and Testing

• Inspect All Connections: Double-check all connections, ensuring they are tight and secure.
• Conduct a Test Burn: Start a small fire and observe the draft. Smoke should rise quickly and cleanly up the chimney. Monitor the insert and surrounding areas for any signs of leaks or overheating.
• Carbon Monoxide Detectors: Ensure you have working carbon monoxide detectors in your home, especially near sleeping areas.

Frequently Asked Questions (FAQs)

Here are some frequently asked questions to further clarify the installation process:

1. Can I install a wood burning insert myself, or do I need a professional?

While technically possible to DIY, installing a wood burning insert is a complex and potentially dangerous project. I strongly recommend hiring a certified professional to ensure proper installation and compliance with local codes. Incorrect installation can lead to chimney fires, carbon monoxide poisoning, and voided warranties.

2. How much does it cost to install a wood burning insert?

The cost can vary widely depending on factors such as the insert’s price, the complexity of the installation, and labor costs in your area. Expect to pay anywhere from $2,000 to $5,000 or more, including the insert, liner, and professional installation.

3. How often should I clean my chimney after installing a wood burning insert?

Chimney cleaning frequency depends on how often you use the insert and the type of wood you burn. At a minimum, have your chimney inspected and cleaned annually. If you burn a lot of wood, especially unseasoned wood, you may need to clean it more frequently.

4. What type of wood should I burn in my wood burning insert?

Always burn seasoned hardwoods, such as oak, maple, and ash. Seasoned wood has a moisture content of less than 20%, which burns hotter and cleaner, producing less creosote. Avoid burning softwoods, painted wood, or treated wood.

5. What is creosote, and why is it dangerous?

Creosote is a highly flammable byproduct of burning wood. It builds up in the chimney and can ignite, causing a dangerous chimney fire. Regular chimney cleaning is essential to remove creosote buildup.

6. What is a chimney liner, and why is it necessary?

A chimney liner is a protective barrier that lines the inside of your chimney. It prevents corrosive gases from damaging the chimney structure and helps contain any chimney fires. It also ensures proper draft for your insert.

7. How do I know if my wood burning insert is working properly?

A properly functioning insert will produce a strong draft, burning wood efficiently and cleanly. The exhaust should be clear or light gray. If you notice excessive smoke, poor draft, or a strong odor of wood smoke in your home, there may be a problem.

8. What are the signs of a chimney fire?

Signs of a chimney fire include a loud roaring sound, dense smoke coming from the chimney, sparks or flames shooting from the chimney, and a strong burning odor. If you suspect a chimney fire, evacuate the house and call 911 immediately.

9. Can I vent my wood burning insert into an existing fireplace flue?

Generally, no. Modern codes require a dedicated stainless steel chimney liner for wood burning inserts. Using the existing fireplace flue can be dangerous and is often against code.

10. Do I need a permit to install a wood burning insert?

Yes, in most jurisdictions. Contact your local building department to obtain the necessary permits before starting the installation. This ensures that the installation meets all safety codes and regulations.

11. What is a block-off plate, and why is it important?

A block-off plate seals the area between the insert and the chimney, preventing heat loss up the chimney and cold air from entering the room. This improves the efficiency of the insert and reduces drafts.

12. How can I improve the efficiency of my wood burning insert?

Use seasoned wood, clean your chimney regularly, ensure proper airflow, and consider using a catalytic combustor insert or adding a blower. Also, ensure your home is well-insulated to prevent heat loss.

By following these steps and consulting with qualified professionals, you can safely and effectively install a wood burning insert and enjoy the warmth and ambiance it provides for years to come. Remember that safety should always be your top priority.