Finished spalted maple bar with a beautiful natural edge and rustic finish

DIY Spalted Maple Basement Bar - Build a Custom Rustic Bar

I knew that I wanted to build a bar in the speakeasy but I wasn't exactly sure of the style. My initial thought was to make a walnut topped bar but then I walked into my local miller's shop and fell in love with the figure of this spalted maple slab. Let's be clear, it did not look this way when I bought it but the figure was there. It had natural curves and wasn't too live edgy. Spalted maple can have some beautiful lines created by fungi - the lines are a result of the nutrient trails of the fungus rotting the wood. The key is to find wood that is rotted enough to look cool but not so much that it causes structural issues.

Project difficulty illustration with cartoon cat

Project Overview

Difficulty Level: Intermediate

Time Required: Weekend Project

Note: Multiple steps over several days to allow for finishing

Understanding Spalted Maple

Spalted maple is a fascinating material created when fungi begin to colonize maple wood. The black lines you see are actually barriers that the fungi create to defend their territory from other fungi. Woodworkers prize these unique patterns, but timing is everything.

For this project, you want wood that has enough spalting to display beautiful patterns but hasn't degraded to the point where it's soft or punky. When selecting a slab:

Look for well-defined dark lines with contrasting light areas
Avoid areas that feel soft when you press firmly with your thumbnail
Choose a piece with a moisture content under 12% to prevent warping
Consider both the top and edges of the slab for visual interest

The warm polyurethane finish I chose enhances these natural patterns without obscuring them, giving the wood a rich amber glow that complements my speakeasy's overall aesthetic.

Close-up of spalted maple grain pattern showing fungal lines

Video Walkthrough

This 3D rendering shows the basic construction approach for the bar. It provides a visual guide to help you understand the frame structure and how the components fit together.

Pro Tips for a Perfect Finish

Expert advice to ensure your spalted maple bar comes out looking professional

Temperature Matters

Apply polyurethane in a well-ventilated area between 65-75°F (18-24°C) with moderate humidity. Extreme temperatures or humidity can cause bubbling or slow drying.

Dust Is Your Enemy

After sanding, vacuum thoroughly, then wipe with mineral spirits on a lint-free rag. Allow it to dry completely before applying finish. Consider a tack cloth for final dust removal.

Multi-Layer Reinforcement

For extra stability, consider adding a plywood backer underneath the spalted maple. This provides additional support for any potentially weaker spalted areas.

Spalted Maple Bar FAQs

Common questions about building with spalted maple

Yes, spalted maple is safe to use for a bar top once properly sealed with polyurethane. The fungi that create the spalting are no longer active after the wood is dried, and the polyurethane creates a food-safe barrier that prevents any interaction with the wood. Just ensure your wood is properly dried (below 12% moisture content) before finishing.

For minor soft spots in spalted maple:

Use thin CA glue (cyanoacrylate) to harden soft areas - apply a few drops and let it soak in
For larger soft areas, consider epoxy stabilization - pour thinned epoxy over the area and let it penetrate
Allow plenty of drying time between applications
Sand carefully after hardening to avoid creating depressions

Very soft or punky areas may indicate the wood is too degraded and should be avoided entirely.

A properly applied oil-based polyurethane finish on a bar top should last 5-10 years under normal use. The durability depends on usage, exposure to direct sunlight, and maintenance. To extend the life of your finish, use coasters for hot items, clean spills promptly (especially alcohol), and avoid abrasive cleaners. You can refresh the finish by lightly sanding and applying a new top coat after several years.

Spalted maple slabs can be found through several sources: local sawmills and specialty wood suppliers often carry them; search Facebook Marketplace or Craigslist for local woodworkers or millers; woodworking specialty stores sometimes stock character woods; online retailers like Bell Forest Products or Cook Woods offer spalted maple slabs with shipping. Prices vary widely based on size, figure, and extent of spalting, typically ranging from $8-20 per board foot.

Yes, LED strip lighting works excellently under a bar overhang. Plan for this during construction by creating a small channel or recessed area to hide the LED strips. Use warm white LEDs (2700-3000K) to complement the amber tones of the spalted maple with warm polyurethane. Be sure to include access for power and potentially a switch or dimmer. Diffused LED strips provide the most even lighting without visible hotspots.

Project Cost Breakdown

Estimated expenses for building a spalted maple bar

Item	Cost
Spalted Maple Slab (30-40 board feet)	$300-500
2x4 Framing Lumber	$30-50
1x3 and 1x6 Boards for Facade	$40-80
Wood Stain and Polyurethane	$40-60
Hardware (Screws, Glue, etc.)	$20-30
Total	$430-720

*Costs will vary based on your location, wood source, and specific materials chosen

Background image of finished speakeasy bar arcade

Complete Your Speakeasy

This bar is just one element of our complete DIY basement speakeasy arcade project. Discover how to build the hidden bookcase door, install rustic lighting, and create the ultimate entertainment space.

View Complete Speakeasy Project

Tools You'll Need

Circular Saw

For cutting 2x4 framing and panels

Orbital Sander

Essential for surface preparation

Drill

For screwing components together

Belt Sander

Optional but helpful for shaping edges

Materials Needed

Spalted Maple Slab

1.5" thick or greater for the bar top

2x4 Lumber

For the frame construction

1x3 and 1x6 Boards

For façade and decorative elements

Minwax Warm Polyurethane

For finishing and protecting the bar top

Wood Screws

Various sizes for assembly

Wood Glue

For reinforcing joints

Step-by-Step Instructions

Raw spalted maple slab showing fungal patterns

1Choose the Right Slab

Look for kiln-dried spalted maple with interesting figure and minimal moisture content (under 12%). The slab should be planed and relatively flat without major dips or wobbles. Avoid excessively rotted areas that might compromise structural integrity.

Sanded spalted maple showing improved grain pattern

2Sand the Slab

Start with 80-grit sandpaper on an orbital sander to smooth the surface. Use flap sanding wheels to address any small areas of rot. Work up to 120-grit for the final surface. For edges, a belt sander can help shape natural curves, but move quickly to avoid creating uneven areas.

Planning the layout of the bar top pieces

3Plan and Cut the Bar Layout

Visualize how the slab can be used to create a flowing bar design. For mine, I cut the slab on one side and split that cut in half to create side pieces. Clamp pieces together and sand across seams to create a unified flow, even if grain doesn't precisely match.

4Build the Frame Base

Create a sturdy 2x4 frame core with dimensions that properly support your bar top. For my bar, I used 49" lengths for the front and back, with 27" cross pieces. Ensure the frame has supports positioned where they'll be hidden by the bar top.

Decorated front panel with vertical slat design

5Create Decorative Panels

Build three panels (front and sides) using 1x3s and 1x6s in a pattern that matches your aesthetic. I arranged mine vertically with a 1x6 horizontal support. Secure panels to the 2x4 frame, making sure to nail from the interior so no nails show on the exterior.

6Stain the Base

Sand the entire base with 120-grit sandpaper. Apply wood stain with a rag, wiping off excess immediately. For added character, I dabbed small amounts of contrasting stains on select boards before applying the main stain to create subtle depth.

Bar top mounted to base before final finishing

7Mount and Shape the Bar Top

Temporarily secure the main slab with screws from underneath, then position side pieces. Sand across all pieces as a unit to create smooth transitions between sections, particularly at the corners which should be rounded for a natural flow.

Applying polyurethane finish to the spalted maple

8Apply Polyurethane Finish

Clean the slab thoroughly with mineral spirits. Apply 3 thin coats of Minwax Warm Polyurethane using a quality brush. Use the feathering technique (light brush strokes from end to end) to eliminate bubbles and ensure an even coat. Allow proper drying time between coats.

Completed spalted maple bar installed in basement

9Final Assembly

Once the polyurethane has dried sufficiently (allow at least 48 hours after the final coat), apply wood glue to the support frame, align all pieces precisely, and secure with clamps or weights. Drive additional screws through the base into the slab for permanent attachment.