Chapter 10 | Building Structures, Finishes, and Site Flashcards
What is the purpose of a foundation?
Distributes the weight of the building so that the building does not experience excessive shifting or settling
What is the enemy of foundations?
Water
What exterior system is exposed to the harshest conditions?
Roof
What are the effects of the 7 environmental conditions on roofing materials?
- Direct sun: can destroy water proofing materials
- Rain: Can pool on flat roofs, or build an ice dam
- Snow: Can build up and cause the roof to collapse
- Ice: Can crack and lift the roofing material
- Wind: Can lift and remove roofing material
- Dirt and pollution: Can destroy the roofing material
- Workers walking on the roof: Possibly damaging to the UV light protection or water proofing later
What is the function of a roof deck?
Supports the roofing and prevents excessive shifting and deformation of the roofing
What are the four types of materials that roof decks are commonly made from?
- Wood
- Steel
- Concrete
- Gypsum-Concrete
Describe WOOD as a roof deck material
- Typically a composite material, it is light and relatively inexpensive
- A slip sheet must be installed between the deck and the roofing to prevent changes in the wood from damaging the roofing
Describe STEEL as a roof deck material
- Strong and stiff
2. Frequently used for flat roofs
Describe CONCRETE as a roof deck material
- Can be cast in place or preset
2. Concrete shingles are also available for pitched roofs
Describe GYPSUM-CONCRETE as a roof deck material
- Similar to concrete, but usually lighter
2. Not strong and not suitable for buildings with high humidity interiors
What is the function of the vapor barrier in a roofing system and where should it be located?
Function: Prevents moisture from condensing in the insulation or on the surface of the deck
Location: Placed between the warm interior of the building and the insulation
What is the function of the air gap and where should it be located?
Function: Air moves through the gap, carrying heat away that has moved through the roof. Helps keep your roof cool
Location Between insulation and the roof deck
What is the difference between coal-tar pitch and asphalt?
- Asphalt is stronger, more rigid, and doesn’t require UV protection
- Coal-tar is self-sealing but does require UV protection (layer of gravel usually)
What are the four different types of materials used on pitched roofs?
- Composite shingles: Fiberglass reinforced asphalt shingles
- Exotic shingles: wood, concrete, slate, tile, etc.
- Rolled roofing: Can have same appearance as composite shingles
- Metal: Can be rolled or shingles
What happens if a roof covered in fiberglass reinforced asphalt shingles gets too hot?
The shingles will curl and crack