Building Enveloppe Flashcards
What is a Building Envelope?
- Separates the interior from the exterior
- Protects buildings from climate
- Maintains an indoor environment according to use/occupancy
What are the Building Envelope Requirements? Name all 12.
- Control water vapour flow
- Control rain penetration
- Control light
- Control heat flow
- Control airflow
- Control sound
- Control solar radiation
- Control noise
- Control fire
- Provide strength and rigidity
- Adjust to movement
- Weather gracefully
What are the basic principles and key elements of a building envelope?
The basic principle is an insulated exterior wall with air and vapour barriers to control the flow of air, heat, and moisture.
- Roofing materials that provide a water-resistant covering
- Flashing materials that prevent water ingress and leaking
- Exterior walls that provide protection from the weather
- Insulating materials that control heat loss and heat gain
- Air and vapour barriers that control the flow and air moisture
- Expansion joints that allow building materials to expand and contract due to temperature variations
Building envelope design is a process that merges _________, __________, and ___________.
- Art
- Science
- Craft
The first line of defence against the movement of water vapour is called the ____________.
Vapour Barrier
When designing a building envelope, how do you arrange the materials according to their permeability?
a. From inside to outside: Most permeable to least permeable.
b. From inside to outside: Least permeable to most permeable.
b. From inside to outside: Least permeable to most permeable.
Water vapour can move in two ways. Name them.
- Air Current
- Vapour Diffusion
Must an air barrier membrane be vapour permeable? Why/Why not?
Yes. An air barrier can be a vapour barrier, but a vapour barrier can’t be an air barrier.
Name the 3 principal methods of heat transmission.
- Convection
- Conduction
- Radiation
What is the basic principle of how thermal insulation works?
Heat moves from warmer to colder areas.
What are the 3 requirements for a vapour barrier?
- Interior humidity levels
- Exterior temperature
- Wall assembly
What are the 3 sources of water in any wall?
- Studs
- Concrete
- Ext. and Int. moisture
Define “R-value”
The R-value is the measure of the ability of a material to resist heat flow.
Define “U-value”
The U-value is the measure of the ability of a material to conduct heat flow.
What is a vapour barrier?
A vapour barrier is any material used for damp proofing, typically a plastic or foil sheet, that resists diffusion of moisture through the wall, floor, ceiling, or roof assemblies of buildings and of packaging to prevent interstitial condensation.
