Moisture
- Rising dampGround moisture drawn upward through porous masonry by capillary action.
- Penetrating dampMoisture entering horizontally through the building envelope from an external source.
- CondensationMoisture depositing on surfaces that are at or below the dew point of the surrounding air.
- Interstitial condensationCondensation forming within the construction rather than on its surface.
- Dew pointThe temperature at which air becomes saturated and moisture condenses out of it.
- Hygroscopic saltsSalts in masonry that absorb atmospheric moisture, producing damp readings and staining after the original source is gone.
- Damp proof course (DPC)A barrier built into a wall to prevent ground moisture rising through it.
Movement
Fabric
- SpallingConcrete breaking away as the embedded steel reinforcement corrodes and expands.
- CarbonationReaction of atmospheric carbon dioxide with concrete, reducing its alkalinity.
- Chloride attackSalt penetrating concrete and causing the reinforcement to corrode.
- Lime mortarTraditional permeable mortar that allows moisture movement and evaporation.
- BreathabilityThe capacity of a construction to allow moisture vapour to pass through and evaporate.
- Wet rotFungal decay of timber confined to the area kept wet by a moisture source.
- Dry rotFungal decay that can transport moisture and spread through masonry into previously dry timber.
Performance
- Thermal bridgeA path of higher heat loss through the building fabric, creating a locally cold internal surface.
- Temperature factor (fRsi)A measure of how warm an internal surface stays relative to indoor and outdoor temperature, used to assess mould risk.
- U-valueThe rate of heat loss through a building element, in watts per square metre per kelvin.
- Air permeabilityThe rate of uncontrolled air leakage through the building envelope.
- Performance gapThe difference between a building's modelled energy performance and its actual measured consumption.
- EPCEnergy Performance Certificate. An asset rating based on modelled assumptions.
- Embodied carbonCarbon emitted in producing, transporting and constructing a building's materials.
- Fabric firstImproving the building envelope before adding or upgrading services.
Contract
- Schedule of conditionA dated, photographic record of a building's condition at a point in time.
- DilapidationsA claim by a landlord against a tenant for breaches of repairing obligations, usually at lease end.
- Defects liability period (DLP)The period after practical completion during which the contractor remains obliged to rectify defects.
- Practical completionThe point at which works are sufficiently complete for the client to take possession.
- SnaggingIdentification and recording of defects and incomplete work before or at handover.
- RetentionA percentage of the contract sum withheld until defects are rectified.