047 Wood Siding Boot Camp: Types, Woods & How They Were Made

Wood siding is easy to overlook. We see it on barns, houses, workshops, and historic buildings and often think of it simply as the material covering the outside.

But wood siding is much more interesting than that.

The shape of a siding board determines how water moves across a wall. The species of wood affects durability, movement, weight, workability, and appearance. The way siding was sawn and milled can provide clues about when a building was constructed or remodeled.

And on some old buildings, siding wasn't installed over layers of modern sheathing and house wrap. It could be a much more important part of the wall itself.

Welcome to Wood Siding Boot Camp.

What Does Siding Actually Do?

The most obvious job of siding is to protect a building from weather.

Rain hits the wall, runs downward, and needs to be directed away from the structure. Good siding accomplishes this by overlapping boards, interlocking edges, or creating joints that resist water penetration.

Siding also protects the framing from sunlight and physical damage while giving a building much of its architectural character.

Before modern plywood, OSB, house wrap, flashing tapes, and manufactured siding systems, builders accomplished all of this with remarkably simple combinations of wood, nails, geometry, and good craftsmanship.

Clapboard and Bevel Siding

Clapboard is one of the classic forms of American wood siding.

A clapboard is installed horizontally, with each board overlapping the board below it. This creates a series of small slopes that naturally shed rainwater.

Bevel siding is closely related. A bevel siding board is thicker along its lower edge, or butt, and becomes progressively thinner toward its upper edge.

That taper allows the upper portion of one board to slide underneath the board above it while leaving a substantial exposed lower edge.

The result is simple, attractive, and remarkably effective.

How Were Beveled Boards Made?

There are several ways to produce tapered siding.

Historically, clapboards could be split from logs, producing boards that followed the natural grain of the tree. Later, sawmills made it possible to produce siding much more rapidly and consistently.

A board or cant could be sawn in a way that produced alternating tapered pieces, allowing much of the original wood to be used rather than planing away a large portion of it.

As woodworking machinery improved, specialized siding machines and planers could produce consistent profiles in large quantities.

The tool marks left behind can sometimes provide clues about how old siding was manufactured.

Dutch Lap Siding

Dutch lap siding has a more pronounced profile than ordinary bevel siding.

The upper portion of the board is shaped so that the next board overlaps it while creating a distinctive shadow line.

Depending on the particular profile, Dutch lap siding may also be called German siding, cove siding, novelty siding, or by other regional and trade names.

Those names can become confusing because mills sometimes used different names for very similar profiles.

The important thing is to look at the actual shape of the board rather than relying entirely on the name.

Tongue-and-Groove Siding

Tongue-and-groove siding works differently.

One edge of the board has a projecting tongue while the opposite edge contains a matching groove. When the boards are installed, the tongue of one board fits into the groove of the next.

This helps align the boards and closes much of the joint between them.

Tongue-and-groove boards can be installed horizontally, vertically, and sometimes diagonally depending upon the building and design.

The profile is also commonly used for interior walls, ceilings, porch ceilings, and flooring.

Shiplap

Shiplap is often confused with tongue-and-groove siding, but the joint is different.

Instead of a tongue fitting into a groove, each board has a rabbet along its edge. The rabbets overlap when the boards are installed.

The joint is simple to manufacture and provides good coverage while still allowing the boards to expand and contract.

Long before shiplap became an interior decorating trend, it was a practical building material.

Board-and-Batten

Board-and-batten siding takes another approach.

Wide boards are installed vertically with small gaps between them. Narrower strips called battens are then installed over those joints.

The battens protect the gaps from direct rain while allowing relatively wide boards to be used.

Board-and-batten siding became particularly common on barns, agricultural buildings, workshops, and houses where a strong vertical appearance was desired.

Novelty Siding

As woodworking machinery became increasingly sophisticated, mills developed many siding profiles.

These are often grouped under the broad term novelty siding.

A novelty siding board might incorporate a rabbet, bevel, cove, channel, or decorative edge. Some profiles were designed to imitate traditional clapboards while allowing faster installation.

When restoring an old building, matching an obsolete novelty siding profile can sometimes become a woodworking project of its own.

Why Wood Species Matters

Not every wood makes equally good siding.

Builders traditionally favored woods that were locally available, relatively stable, reasonably easy to work, and capable of surviving repeated exposure to moisture.

Transportation also mattered enormously.

A builder in nineteenth-century Pennsylvania or New York normally had little reason to purchase expensive lumber transported across the continent when enormous quantities of suitable timber were available much closer to home.

As railroads expanded and regional lumber supplies changed, however, wood increasingly traveled long distances.

Eastern White Pine

Eastern white pine was one of the great building woods of northeastern North America.

It is lightweight, relatively stable, easy to saw and plane, and available in large dimensions from mature trees.

White pine was used for siding, trim, doors, windows, paneling, flooring, framing, and countless other parts of buildings.

Properly maintained and kept from remaining wet, old-growth white pine siding can survive for an extraordinary length of time.

Yellow Pine

The name yellow pine can refer to several related southern pine species rather than one particular tree.

Southern yellow pine is generally harder, heavier, stronger, and more resinous than eastern white pine.

Its pronounced growth rings can produce an attractive grain, and the harder latewood bands are often immediately noticeable when working it.

Yellow pine has been used for framing, flooring, trim, siding, and many other building applications.

Cedar

Cedar became highly valued for exterior applications because several cedar species have good natural resistance to decay.

Cedar has been used for clapboards, shingles, shakes, trim, fences, and other components exposed to weather.

Its relatively low weight and dimensional stability also make it well suited to siding.

Hemlock

Eastern hemlock was abundant throughout much of the Northeast and became an important construction lumber.

It was commonly used for framing, sheathing, barns, and other utilitarian construction.

Hemlock can be coarse, splintery, and sometimes frustrating to work. Its tendency to produce stubborn splinters is familiar to anyone who has handled much rough hemlock lumber.

Although it could be used for exterior boards, it was not necessarily the first choice for high-quality finished siding when better material was available.

Spruce and Fir

Spruce and true fir species have also been used for building materials, particularly in northern regions where they were readily available.

Balsam fir is native to northeastern North America. Its wood is generally lightweight, relatively soft, and light colored when freshly cut.

Douglas-fir presents a completely different story.

Despite its name, Douglas-fir is not a true fir. It is a western North American species renowned for its strength and structural properties. As transportation networks developed, Douglas-fir eventually became an important building material far beyond its natural range.

When identifying siding on a nineteenth-century eastern building, therefore, geography and construction date can be almost as important as the appearance of the wood itself.

Three Buildings, Three Siding Stories

Our own projects provide three interesting examples of traditional wood siding.

Zehr Escape — White Pine Tongue-and-Groove

Zehr Escape uses white pine tongue-and-groove siding.

The interlocking profile helps align the boards and creates a clean exterior surface while allowing the natural character of white pine to remain an important part of the building.

Zehr Retreat — Yellow Pine Dutch Lap

Zehr Retreat uses yellow pine Dutch lap siding.

The harder, more pronounced grain of yellow pine gives the siding a different character from white pine, while the Dutch lap profile creates strong horizontal shadow lines.

Zehr Estate — Historic Beveled Clapboard

Zehr Estate presents a much older and more mysterious example.

The main house dates to 1854, with substantial work occurring around 1874. Its exterior uses beveled clapboard siding approximately six inches wide, with boards tapering from a thicker lower edge to a much thinner upper edge.

The species has not yet been positively identified.

The wood is relatively lightweight, darker in appearance, and can be noticeably stringy. Possibilities worth investigating include regional softwoods and, perhaps, fir species.

Original pieces have been saved, making future comparison of end grain and freshly exposed surfaces possible.

A Fascinating Clue From 1950

An addition constructed at Zehr Estate around 1950 also uses wood siding that appears remarkably similar to the siding on the older house.

The later boards are somewhat wider, but the wood itself looks and feels very similar.

If samples from both sections prove to be the same species, that could provide an important clue. By 1950, lumber distribution was dramatically different from what it had been in 1854 or 1874.

On the other hand, matching species would not necessarily mean that both sets of siding were installed at the same time. Builders repairing or expanding an old house often tried to match existing materials.

The two samples may eventually help tell us more about both the wood and the history of the building.

When the Siding Is More Than a Covering

Modern wall construction often consists of studs, structural sheathing, a weather-resistant barrier, and finally the exterior siding.

Historic construction can be very different.

At Zehr Estate, portions of the house have solid boards on the inside of the wall framing while the exterior clapboards are attached directly to the framing. There is no second layer of exterior board sheathing hiding underneath the siding.

This makes the original siding especially important.

Removing it would expose the framing itself, and replacing all of it around the elaborate architectural details of the house would have been a considerable undertaking.

Construction details like these can become valuable evidence when trying to determine whether siding is original or represents a later remodeling.

Sometimes Old Builders and Modern Woodworkers Reach the Same Solution

There is an interesting personal connection to the wall construction at Zehr Estate.

About twenty years before purchasing the Estate, I built my own woodshop using a similar idea: solid boards on the inside with siding forming the exterior surface.

I had no idea at the time that builders working on Zehr Estate generations earlier had used essentially the same approach.

That is one of the fascinating things about woodworking and construction. Sometimes a practical problem leads builders separated by more than a century toward surprisingly similar solutions.

Old Siding Can Help Date a Building

When investigating historic siding, don't look only at the wood species.

Look at everything.

• Board width and thickness
• Siding profile
• Saw marks
• Planer and molding-machine marks
• Nail type and nail placement
• Paint layers
• Weathering
• End grain
• Growth-ring patterns
• Joints around windows and doors
• Evidence of earlier siding underneath
• Changes where additions meet the original building

A single clue rarely proves the age of siding, but many clues considered together can tell a surprisingly detailed story.

Don't Throw Away That Old Board

When restoring an old building, even a damaged piece of original siding can be valuable.

A saved section provides a physical record of the original profile, thickness, exposure, nail placement, wood species, tool marks, and construction technique.

It can also become the pattern needed to reproduce replacement siding decades later.

Whenever practical, label saved pieces with their original location and approximate date of removal. What looks like scrap today may become extremely useful evidence tomorrow.

Wood Siding Is a History Lesson

A piece of siding can tell us much more than what color a house used to be.

It can tell us about the trees growing in a region, the capabilities of local sawmills, changing woodworking machinery, transportation networks, architectural styles, and the decisions made by builders generations ago.

White pine tongue-and-groove at Zehr Escape, yellow pine Dutch lap at Zehr Retreat, and unidentified nineteenth-century clapboard at Zehr Estate represent three different approaches to the same basic problem:

How do we use wood to protect a building from the weather?

The profiles change. The species change. The tools change.

But the basic woodworking principles remain remarkably familiar.

And sometimes, without ever seeing the old builder's work, a modern woodworker arrives at the very same solution.