What is a flood spillway?
A flood spillway is a deliberately lowered section of embankment over which floodwater is allowed to flow in a controlled way. How it works and how it is sized.
What is culverting?
Culverting is covering over a watercourse, road or square with a structure so the space above becomes usable. Applications and maintenance issues.
What is diagonal placement?
Diagonal placement means set at an angle, usually 45 degrees. Where it is used in brickwork, tiling, buttresses and timber joints, and what to watch.
What is overhand bricklaying?
Overhand bricklaying means laying brick from the inside face while the outside stays fair-faced. How it works, why it is used and what to watch.
What is surface resistance?
Surface resistance is the thermal resistance of the air layer at a building surface (Rsi and Rse). Standard values and how it relates to the U-value.
What is overpressure?
Overpressure is a pressure above the surrounding pressure. What it means in drainage, in a sealed heating system and in a blower door test.
What is oversizing?
Oversizing is deliberately making a component larger than strictly required. Where the margin is worth having and where it costs money and performance.
What is an encroachment?
An encroachment is a building part that extends over, on or under a neighbouring property. What it means legally and structurally, and how to avoid one.
What is an ornament?
An ornament is a decorative building element with no load-bearing function. Types, materials, style clues and how to repair ornamentation.
What is orientation?
Orientation is the position of a building relative to the sun and prevailing wind. What each facade direction does, and how to avoid overheating.