Close-up of original quarter sawn riven oak clapboards in leanto attic

Clapboard (), also called bevel siding, lap siding, and weatherboard, with regional variation in the definition of those terms, is wooden siding of a building in the form of horizontal boards, often overlapping. ''Clapboard'', in modern American usage, is a word for long, thin boards used to cover walls and (formerly) roofs of buildings. Historically, it has also been called ''clawboard'' and ''cloboard''. In the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

and

New Zealand New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...

, the term ''weatherboard'' is always used. An older meaning of "clapboard" is small split pieces of oak imported from Germany for use as

barrel A barrel or cask is a hollow cylindrical container with a bulging center, longer than it is wide. They are traditionally made of wooden stave (wood), staves and bound by wooden or metal hoops. The word vat is often used for large containers ...

staves, and the name is a partial translation (from , "to fit") of Middle Dutch and related to German .

Types

Riven

Clapboards were originally riven radially by hand producing triangular or "feather-edged" sections, attached thin side up and overlapped thick over thin to shed water.Heart side of boards
''PopularWoodworking.com''.

Radially sawn

Later, the boards were radially sawn in a type of

sawmill A sawmill (saw mill, saw-mill) or lumber mill is a facility where logging, logs are cut into lumber. Modern sawmills use a motorized saw to cut logs lengthwise to make long pieces, and crosswise to length depending on standard or custom sizes ...

called a ''clapboard mill'', producing '' vertical-grain'' clapboards. The more commonly used boards in

New England New England is a region consisting of six states in the Northeastern United States: Connecticut, Maine, Massachusetts, New Hampshire, Rhode Island, and Vermont. It is bordered by the state of New York (state), New York to the west and by the ...

are vertical-grain boards. Depending on the diameter of the log, cuts are made from deep along the full length of the log. Each time the log turns for the next cut, it is rotated until it has turned 360°. This gives the radially sawn clapboard its taper and true vertical grain.

Flat-sawn

''Flat-grain'' clapboards are cut tangent to the annual growth rings of the tree. As this technique was common in most parts of the

British Isles The British Isles are an archipelago in the Atlantic Ocean, North Atlantic Ocean off the north-western coast of continental Europe, consisting of the islands of Great Britain, Ireland, the Isle of Man, the Inner Hebrides, Inner and Outer Hebr ...

, it was carried by immigrants to their colonies in the

Americas The Americas, sometimes collectively called America, are a landmass comprising the totality of North America and South America.''Webster's New World College Dictionary'', 2010 by Wiley Publishing, Inc., Cleveland, Ohio. When viewed as a sing ...

and in

and

. Flat-sawn wood cups more and does not hold paint as well as radially sawn wood.

Chamferboard

''Chamferboards'' are an Australian form of weatherboarding using tongue-and-groove joints to link the boards together to give a flatter external appearance than regular angled weatherboards.

Finger jointed

Some modern clapboards are made up of shorter pieces of wood

finger joint A finger joint, also known as a comb joint, is a woodworking joint made by cutting a set of complementary, interlocking profiles in two pieces of wood, which are then Adhesive, glued. The cross-section of the joint resembles the interlocking of ...

ed together with an adhesive.

Wood species

In North America clapboards were historically made of split oak, pine and spruce. Modern clapboards are available in red cedar and pine. In some areas, clapboards were traditionally left as raw wood, relying upon good air circulation and the use of 'semi-hardwoods' to keep the boards from rotting. These boards eventually go grey as the tannins are washed out from the wood. More recently clapboard has been tarred or painted—traditionally black or white due to locally occurring minerals or pigments. In modern clapboard these colors remain popular, but with a hugely wider variety due to chemical pigments and stains. Clapboard houses may be found in most parts of the British Isles, and the style may be part of all types of traditional building, from cottages to windmills, shops to workshops, as well as many others. Clapboard is always referred to as ''weatherboard'' in New Zealand, where that type of cladding dominated in buildings constructed before 1960. After the big

earthquakes An earthquakealso called a quake, tremor, or tembloris the shaking of the Earth's surface resulting from a sudden release of energy in the lithosphere that creates seismic waves. Earthquakes can range in intensity, from those so weak they c ...

of 1855 and 1931, wooden buildings were perceived as being less vulnerable to damage, and weatherboard walls with a

corrugated iron Corrugated galvanised iron (CGI) or steel, colloquially corrugated iron (near universal), wriggly tin (taken from UK military slang), pailing (in Caribbean English), corrugated sheet metal (in North America), zinc (in Cyprus and Nigeria) or ...

roof was found to be a cost-effective building style. Newer, cheaper designs often imitate the form of clapboard construction as siding made of

vinyl Vinyl may refer to: Chemistry * Polyvinyl chloride (PVC), a particular vinyl polymer * Vinyl cation, a type of carbocation * Vinyl group, a broad class of organic molecules in chemistry * Vinyl polymer, a group of polymers derived from vinyl ...

( uPVC),

aluminum Aluminium (or aluminum in North American English) is a chemical element; it has chemical symbol, symbol Al and atomic number 13. It has a density lower than that of other common metals, about one-third that of steel. Aluminium has ...

, fiber cement, or other man-made materials. These materials can provide a lightweight alternative to wooden cladding.

References

External links

Research report containing photos of a clapboard roof in Virginia, U.S.A.
{{Wood products, state=expanded Building materials House styles Wood products