How do I calculate epoxy for a live edge table with irregular edges?

Measure the channel at its widest point (length × max width × depth), then reduce by your void fill percentage. For heavily organic edges with lots of natural character: use 70–78% void fill. For moderately irregular live edges: 78–85%. For relatively clean live edges: 85–90%. This accounts for the wood material that protrudes into the channel.

What void fill percentage should I use for a live edge slab?

Very rough, gnarly live edge with bark: 65–75%. Typical organic live edge: 78–85%. Clean, mostly straight live edge: 85–92%. Bookmatched straight slabs: 88–95%. When uncertain, use 80% and buy 15% extra — running short on a unique slab pour is a costly mistake.

Should I include bark in my live edge table?

Bark that is firmly attached and dense can be left in. Loose, flaky bark should be removed — it will eventually detach and create voids under the epoxy that crack over time. Treat remaining bark with a penetrating sealer before pouring to prevent air and sap from causing bubbles.

Live Edge Table Resin Calculator — Natural Slab Edge Guide

Live edge tables are the most challenging epoxy calculation because no two slabs are identical. The irregular, organic edges mean your river channel is never a simple rectangle — wood protrudes unevenly into the void, bark may or may not be included, and knots can add unexpected volume. This guide explains how to measure correctly and select the right void fill percentage for your specific slab. Use the River Table Calculator with these guidelines for your final volume estimate.

Select River Table mode and enter your channel dimensions — adjust the void fill % based on your edge style below.

🪵 Calculate Live Edge Epoxy ⟶

📐 How to Measure a Live Edge Channel

Getting Accurate Dimensions on Irregular Slabs

Standard river table measurement rules don't account for the organic variation of live edge slabs. Follow this approach for more accurate results:

Measure length: The full length of the channel from end to end — straightforward even on irregular slabs.
Measure width at multiple points: Take width measurements every 6–12 inches along the channel. Average them. This is your channel width input.
Measure pour depth: This is how deep you plan to fill — not always the full slab depth.
Select void fill %: Based on your edge style (see table below). This is the most important adjustment for live edge work.

Epoxy (fl oz) = L × avg_W × D × void_fill% ÷ 1.805 × (1 + waste%)

🌿 Void Fill % by Edge Style

Choosing the Right Void Fill for Your Slab

The void fill percentage is the most critical variable for live edge work. It compensates for wood material intruding into the channel space:

Edge Style	Void Fill %	Description
Very gnarly, deeply sculpted	65–72%	Heavy undulations, deep pockets of wood
Rough organic live edge with bark	72–78%	Bark intact, irregular protrusions
Typical organic live edge	78–85%	Most common — moderate undulations
Relatively smooth live edge	85–90%	Natural but less dramatic edge character
Clean live edge, minimal features	88–93%	Lightly profiled, nearly straight
Bookmatched straight slabs	90–96%	Paired slabs, mirror image cut

When in doubt, use a lower void fill % (meaning more epoxy) and buy extra. Overestimating void fill leads to running short — a serious problem with unique slabs where you can't easily match a second batch.

🪵 Preparation Tips

Getting Your Live Edge Slab Ready for Epoxy

Remove loose bark: Only keep bark that is firmly attached and dense. Loose bark will detach under epoxy, creating invisible voids that crack later.
Seal the wood first: Apply a thin seal coat (brush or roll) to all wood surfaces that will contact epoxy 24 hours before the main pour. This prevents air pockets from escaping wood grain during curing.
Fill cracks and knots: Use a heat gun or torch to pop small bubbles rising from the wood during and after each pour. Cracks in the wood can also be pre-filled with a thin epoxy pour to stabilize them.
Check moisture content: Wood moisture above 12–15% causes bubbling and adhesion problems. Let freshly milled slabs dry for several months or kiln-dry before pouring.
Build a dam: Tape the underside and edges of the slab to contain the pour. Melamine-coated boards work well — epoxy won't stick to them.

📊 Example Estimates by Slab Size

Live Edge Table Epoxy Estimates

Using 80% void fill, 1.5″ depth, 10% waste buffer — typical for a standard organic live edge channel:

Table Length	Avg Channel Width	Net (fl oz)	With 10% Buffer
4 ft (48″)	7″	149 fl oz	164 fl oz (1.3 gal)
5 ft (60″)	8″	213 fl oz	235 fl oz (1.8 gal)
6 ft (72″)	9″	289 fl oz	318 fl oz (2.5 gal)
7 ft (84″)	10″	373 fl oz	410 fl oz (3.2 gal)
8 ft (96″)	11″	468 fl oz	515 fl oz (4.0 gal)

Use your actual averaged channel width and adjust void fill % per the table above for a more accurate estimate.

Frequently Asked Questions

How do I calculate epoxy for irregular live edge slabs?

Measure channel length, average width (multiple measurements), and pour depth. Apply a void fill % between 70–90% based on your edge style (use the table above). Divide cubic inches by 1.805 for fl oz, then add a 15% waste buffer. The River Table Calculator handles all of this automatically.

What void fill % for a typical live edge table?

For most organic live edge slabs with moderate natural character: use 78–85%. For heavily sculpted, gnarly edges: drop to 70–75%. For clean, relatively straight live edge: use 87–92%. When unsure, always go lower (more epoxy) and buy an extra 15% buffer.

Should I keep the bark on my live edge table?

Only if the bark is firmly attached, dense, and dry. Test by pressing a fingernail firmly against the bark — if it separates easily, remove it. Loose bark detaches under epoxy pressure and thermal cycling, creating hidden voids that eventually cause cracks or delamination.