SAH Archipedia uses terms from the Getty Art and Architecture Thesaurus (AAT) to categorize and classify metadata for the entries in the database. For more information on the Getty AAT, click here

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half-timber construction

The vernacular building technique in which the spaces between the heavy supporting timbers are filled with brick, wattle and daub, or other material. The term is also used to describe buildings with a false-timber frame attached to the outside wall to give the appearance of half-timber construction.

hammer-beam trusses

Trusses of the type utilized in hammer-beam roofs, with a combination of hammer beams, hammer posts, and braces taking the place of the beam at the base of the roof.

handmade brick

Any brick molded by hand before firing; a brick mold or stock may be used. Due to the fact that it is less uniform than machine-made brick, it is sometimes preferred for facing.

hard-burned brick

A brick that has been burned at high temperature, yielding high compressive strength and durability and low absorption.


Wood produced from broad-leaved deciduous trees, varying widely in color and grain pattern; usually but not always harder than softwood. Examples of hardwood trees are ash, beech, birch, cherry, mahogany, maple, oak, poplar, and walnut. Hardwood trees are found in temperate and tropical climate zones. Most of the wood used for cabinetry, furniture and flooring is obtained from hardwood trees; only a small amount of hardwood is used for paper pulp. The term hardwood is somewhat confusing since some deciduous trees, such as basswood, have timber that is softer than some coniferous trees, such as yellow pine.

hay (material)

General term for material comprising grass that has been mown, cut, and cured; often used as fodder.

heat-absorbing glass

Glass that absorbs heat because it is opaque to infrared radiation; it nevertheless retains a reasonable degree of transparency to most other radiation.


Lines of closely spaced hedges typically interspersed with trees, usually planted on a low earthen wall or base and trained to form a barrier or mark the boundary of an area, particularly in fields or between properties.

hematite (mineral)

A metallic black-gray or dark red mineral primarily composed of iron oxide found throughout the world, although the largest source is a sedimentary deposit in the Lake Superior district in North America. It occurs in many physical forms: specular ore (steel gray color, shiny crystals); micaceous hematite (gray, scaly flakes), red ocher (soft, fine-grain, red powder); kidney ore (massive, gray botryoidal form), and pencil ore (gray, fibrous crystals). Because hematite has a high iron content (70%), it is primarily used for smelting iron. It also has been used since ancient times as a red pigment in paints and glazes, for seals, beads, and small carvings since the early 3rd millineum. It is also used as jewelers' rouge for polishing glass and to produce the sparkle in aventurine ceramic glazes.

hemlock (wood)

Wood of the tree from the genus Tsuga. The bark contains tannin, used in the tanning industry, and the timber is mostly light in color with a pinkish tinge, and the soft, and coarse-grained, used in construction of boxes.

herbaceous plants

Perennial plants which have no woody stem, and which can be divided into three types: annuals, biennials, and herbaceous perennials.


Any chemical agent that is toxic to some or all plants, particularly those categorized as weeds. Historically a variety of substances have been used including salts, carbon disulfide, borax, pyridine, mercurials, and arsenic trioxide. After 1945 synthetic varieties emerged including: amitrole, picloram, 2,4-D, DDT, atrazine, glyphosate, diquat, and paraquat. Herbicides do not always decompose and have created environmental hazards.

hickory (wood)

Wood of the tree belonging to the genus Carya, valued because it is strong, elastic, and shock resistant. The reddish brown wood has a straight grain and a fine texture that polishes well; used for flooring, tool handles, farm implements, chairs, wheel spokes, golf clubs, baseball bats, and for flavoring smoked food. It is also split into thin canes for weaving. The heartwood is white.


Small hills, small elevations in the earth's surface, or small mounds or heaps of earth or stones.

hip roofs

Roofs which rise to a peak or ridge by inclined planes on all, usually four, sides, therefore requiring hip rafters.

hollow brick

A hollow clay masonry unit whose net cross-sectional area in every plane parallel to the bearing surface is not less than 60% of its gross cross-sectional area measured in the same plane. In British usage it refers to a brick with holes in it that total at least 25% of its volume, the holes being not less than 3/4 in. (1.91 cm) wide or 3/4 sq. in. (4.84 sq. cm) in area.

hollow masonry units

Masonry units whose net corss-sectioned area in any plane parallel to the bearing surface is less than 75% of its gross cross-sectional area measured in the same plane.

honey locust (wood)

Wood of the species Gleditsia triacanthos, native to regions in North and South America, Africa, and Asia. It produces a high quality wood that polishes well, but is lighter and weaker than most locust wood. It is used for specialty furniture, wheel spokes, and posts.

hyacinth (zircon)

A transparent red or brown variety of zircon, sometimes used as a gem.