---
title: "Specification Data"
url: https://ipedeckingsource.com/Ipe-specification
description: "Footage conversion, recommended joist spacing, botanical and common names, weight, mechanical properties and span values by load for Ipe decking."
published: 2026-08-17
updated: 2026-08-17
---

# Specification Data

Published 2026-08-17

The published conversion, span and property figures for Ipe decking and porch flooring, in the order they are used when a deck is drawn.

*Footage conversion*

| Board | Net size | Conversion |
|---|---|---|
| 1 x 6 | 3/4" x 5-1/2" | 100 square feet = 220 lineal feet |
| 1 x 4 T&G | 3/4" x 3-1/2" | 100 square feet = 343 lineal feet |
| 1 x 4 T&G | 3/4" x 3-1/4" | 100 square feet = 370 lineal feet |

*Recommended span*

| Board | Net size | Joist spacing |
|---|---|---|
| 1 x 4 T&G | 3/4" x 3-1/4" | up to 16" on centre |
| 1 x 4 | 3/4" x 3-1/2" | up to 16" on centre |
| 1 x 6 | 3/4" x 5-1/2" | up to 24" on centre |
| 5/4 x 6 | 1" x 5-1/2" | up to 30" on centre |

Recommended joist spacing by board size. Minimum requirements are set locally and are checked before framing.

## Species record

**Family name**: Tabebuia avellandedae, Tabebuia ipe and Tabebuia serratifolia, of the family Bignoniaceae

**Common names**: Ipe, pau d'arco, ipe tabaco, bethabara, lapacho, ebene vert, amata prieto, ironwood, greenheart, amapa, cortez, guayacan, guayacan polvillo, flor amarillo, madera negra, tahuari, lapacho negro, Brazilian walnut

**Height and weight**: Trees routinely grow to 150 feet and can reach 200 feet, with trunk diameters of 6 feet and boles clear to 60 feet or more. Weight varies between 60 and 75 pounds per cubic foot, with a specific gravity of 1.08

**Dimensional stability**: Stable, with minimal checking and warping

**Maintenance**: Low

**Fire rating (NFPA)**: Class A

**Resistance to insects and decay**: High

**Movement in service**: Low

**Weight (lbs per cubic foot)**: 60-75 lbs

**Bending strength (psi)**: 26,000

**Modulus of elasticity (psi)**: 3,308,000

**Hardness (psi)**: 3,650

## Working the material

The material usually air dries rapidly with very slight checking or warping. It can be difficult to work and difficult to saw, and its hardness has a blunting effect on cutting edges. High quality carbide and diamond tipped blades are recommended, as is pre-drilling when surface fastening. Machining generates a fine yellow dust that may cause breathing problems and dermatitis. Ipe is highly resistant to insect and fungal attack.

*Span values, inches by load*

| Nominal size | 40 lbs/sf | 50 lbs/sf | 60 lbs/sf | 100 lbs/sf |
|---|---|---|---|---|
| 1 x 4 | 32 | 30 | 28 | 24 |
| 1 x 6 | 38 | 34 | 32 | 28 |
| 5/4 x 6 | 42 | 38 | 36 | 32 |