How to Build a Brick Arch: A Practical Guide for the Eco-Conscious DIYer

Look, if you’re eyeing a charming brick archway for your home renovation but feel swamped by jargon like embodied energy and U-values, or worried about the cost of going green, you’re not alone. I’ve been in the trenches of sustainable building for 15 years, and believe me, brick arches are more than just pretty curves—they’re a smart, time-tested, and surprisingly affordable way to add character and durability to your home while keeping your environmental footprint in check.

Why Brick? Why an Arch?

Let’s start with the basics. Concrete often gets the blame for high carbon footprints, and timber isn’t always the best fit depending on your climate and maintenance preferences. Brick, especially from reputable sources like Glen-Gery or Belden Brick Company, offers a middle ground. Bricks typically cost between $0.50 to $2.50 per brick, so depending on the size and style of your arch, you can budget accordingly.

Bricks are made from natural clay or shale fired at high temperatures, giving them excellent thermal mass. Think of bricks like a slow cooker in your wall—they absorb heat during the day and release it slowly at night, helping regulate indoor temperatures naturally. This reduces your heating and cooling needs, which is a win for your wallet and the planet.

Now, the arch itself is a marvel of ancient engineering, dating back to Roman aqueducts. It distributes weight evenly, allowing for wider openings without heavy lintels or steel supports. This means you can create a stunning doorway or window that lasts centuries with minimal maintenance.

Common Types of Brick Arches

Before diving into building, it helps to know your options. Here are some popular types of brick arches suited for DIY projects:

Semi-circular (Roman) Arch: A classic half-circle arch, elegant and structurally sound. Segmental Arch: Less than a half-circle, flatter and often used over doorways. Pointed (Gothic) Arch: Two arcs meeting at a point, more complex but striking. Flat Arch: A shallow curve that looks almost straight, requiring precise brick cutting.

For DIYers, I recommend starting with a segmental or semi-circular arch. They’re easier to form and forgiving if your bricks aren’t perfectly uniform.

Step 1: Planning Your Brick Arch

Planning is everything. Measure the width and height of your intended archway. Remember, the wider the span, the more challenging the build. Keep it manageable for your skill level—say, a 3 to 4-foot opening.

Calculate the number of bricks you’ll need. For example, a 3-foot wide semi-circular arch about 1.5 feet tall might require around 40-50 bricks, depending on brick size and mortar joints.

Also, consider the type of brick. Glen-Gery and Belden Brick Company both offer high-quality bricks with good durability and consistent sizing, which makes laying arches easier and your final product stronger.

Step 2: Building a Form for a Brick Arch

This is the backbone of your arch construction, literally. The form (or centering) supports the bricks until the arch is self-supporting.

Materials Needed for the Form:

Plywood or MDF sheet 2x4 lumber for framing Wood screws and nails Jigsaw or handsaw Measuring tape and pencil

How to Build the Form:

Draw the arch shape on your plywood according to your measurements. For a semi-circular arch, you can use a string tied to a pencil to draw a perfect half-circle. Cut out the arch shape carefully with a jigsaw. Attach 2x4 lumber to the back to create a sturdy frame. This frame will rest on your wall or opening and hold the bricks in place during construction. Make sure the form fits snugly within the opening where the arch will go. Optional: Apply a release agent like cooking oil or wax paper on the form surface where bricks will rest, so the form can be removed easily after the mortar cures.

Building a strong, accurate form is crucial. Think of it like the baking pan for your arch—if the pan’s off, the shape won’t hold.

Step 3: Laying the Bricks

Now for the fun part—actually building the arch!

Materials Needed:

Bricks (preferably from Glen-Gery or Belden for quality) Masonry mortar (use a mix suitable for your climate—Type N mortar is common for above-grade applications) Trowel Level and rubber mallet Chalk line or string Brush for cleanup

Step-by-Step Bricklaying:

Start by laying bricks on either side of the opening, creating the vertical supports or "abutments." Spread a bed of mortar on the form, then place the first brick at one side of the arch, pressing it gently into place. Continue laying bricks along the arch, working from both sides toward the center. The bricks should be laid with the narrow edge facing outward (called the "header" or "voussoir" bricks in arch terminology). The final brick placed at the center is the "keystone." This brick locks the arch in place and carries the load. Use the rubber mallet to gently tap bricks into position and check the level frequently. Fill joints with mortar and smooth out for a clean finish.

Patience is key here. Mortar typically takes 24-48 hours to cure enough to remove the form.

Step 4: Removing the Form and Finishing Touches

Once the mortar has cured, carefully remove the wooden form. If you applied a release agent, this should be straightforward.

Inspect the arch for any loose bricks or gaps in mortar. Fill gaps with additional mortar or tuckpointing as needed.

Depending on your aesthetic, you can leave the brick raw for that authentic rustic look or seal it with an eco-friendly masonry sealant to protect against weathering.

Cost and Environmental Impact: The Real Numbers

Material Approximate Cost Environmental Notes Brick (Glen-Gery, Belden) $0.50 - $2.50 per brick Made from natural clay; long lifespan; recyclable Masonry Mortar $8 - $12 per 80 lb bag Contains cement; moderate embodied carbon Wood for Form $20 - $50 (reusable) Can use reclaimed wood to reduce impact

Embodied energy is the total energy required to produce a building material. Bricks have higher embodied energy than timber but much lower than concrete when you factor in durability and lifespan. Plus, bricks’ thermal mass helps with energy savings over time—which timber or concrete alone can’t match.

Pros and Cons of Building a Brick Arch

Pros:
Durable and long-lasting (often outlives the house) Excellent thermal mass for energy efficiency Visually appealing with timeless character Allows wider openings without steel lintels Materials can be sourced locally to reduce carbon footprint
Cons:
Requires skill and patience—building the form and laying bricks is labor-intensive Upfront cost of quality bricks and mortar can be higher than basic timber frames Mortar contains cement, which has a carbon footprint Formwork is temporary but adds time and material use

Final Thoughts: Is a Brick Arch Right for You?

If you want a feature that blends historical charm, practical sustainability, and structural soundness, a brick arch is a fantastic choice. It’s not a “miracle” material—no brick will solve all your green building challenges—but it’s a proven, beautiful solution that makes sense for many DIY home builders who want to avoid plastic-based or high-carbon materials like concrete.

Remember, the key to success is careful planning, quality materials, and patience. Build your form well, choose reliable bricks, and re-thinkingthefuture.com take your time laying each brick with care. Your effort will pay off in a feature that’s as sturdy as a Roman aqueduct and as environmentally friendly as a well-placed garden tree.

And hey, if you want to geek out on arches and bricks, I always carry around a small, worn-out brick sample—don’t hesitate to ask about the Romans sometime!