Laying drains
Ground water (land) drains are laid in trenches at depths of 0.6 and 0.9 m in heavy soils and 0.9 […]
Glossary
Glossary
Foundations on sloping sites
The natural surface of ground is rarely level to the extent that there may be an appreciable slope either across
Glossary
double vault
A vault, usually domical, consisting of an inner shell separated from a higher outer shell.
Glossary
double tenons
1. Two tenons, side by side, at one end of a member; also called a divided tenon. 2. Two tenons,
Glossary
double-lock seam
A type of seam between the edges of adjacent metal sheets; formed by making a double fold, then dressing down to form a
Glossary
double-hung window, double-hung sash window
A window having two vertically sliding sashes, each closing a different part of the window; the weight of each sash is counterbalanced for
Glossary
double-headed nail, scaffold nail, form nail
A nail having two heads, one above the other; the upper head is driven with a hammer, and it is
Glossary
double return stair, side flights
A stair having one flight from the main floor to an intermediate landing and two side flights from that landing to the floor
Glossary
double header
A header joist made of two pieces of lumber, fixed together by bolts or nails, to provide greater strength than a single