Construction Technology Flashcards
(26 cards)
What is the typical buildup of a green roof?
Soil / growing medium – for vegetation.
Filter fabric – prevents small particles from blocking the drainage layer.
Drainage layer – provides an optimal balance between water and air in the system. Affects the amount of storm water which will be retained on the roof. Aims to remove excess water from the substrate.
Root barrier – protects the integrity of the roof from roots of plants that could penetrate the roof’s upper layers.
Waterproof membrane.
What are the different types of green roofs?
Extensive – A green roof with a growing medium of less than 6 inches.
Intensive – A green roof with a growing medium of more than 6 inches.
What are advantages and disadvantages of a green roof?
Advantages:
* Range of Environmental benefits.
* Decreases surface water runoff
* Aesthetically pleasing.
Disadvantages:
* Increased construction costs.
* Increased structural load.
* Requires specialist subcontractors.
What is the typical buildup of a blue roof?
Finish – green roof or paving
Filter fabric - prevents small particles from blocking the drainage layer.
Blue roof attenuation cells
Water flow reducing layer – barrier to rainwater.
Roof Structure & Insulation
What is a blue roof?
A blue roof is a roof intended to control the release of water – typically rainwater. They temporarily store the water for use and control its release.
What is a brown roof?
A brown roof is where soil or a growing medium is left on a roof and is left as it - allowing it to self-seed.
What are the advantages and disadvantages of a blue roof?
Advantages:
* Reuse of water.
* Controls surface water runoff – aids in preventing flooding.
Disadvantages:
* Increased construction costs.
* Increased structural load.
* Requires specialist subcontractors.
How much does a green roof cost?
Around £600/m2 for an intensive green roof, slightly less for an extensive.
How much does a blue roof cost?
Around £400/m2 without a finish
What is a green roof?
Roofs that are purposely fitted or cultivated with vegetation
What are the advantages and disadvantages of using a Steel frame?
Advantages:
* High tensile strength – therefore less need for columns, so increased NIA.
* Off-site manufacture – offers programme advantages.
* Integration of services within the structural elements (castellations – openings in the web)
* Lightweight frame – aids in foundation design.
Disadvantages:
* Poor fire resistance – need for protection.
* Energy intensive to produce.
* Steel price is volatile.
What are the advantages and disadvantages of a concrete frame?
Advantages:
* Better fire resistance than steel.
* Long service life – low maintenance.
* Can be cast to any shape.
* Very high compressive strength.
Disadvantages:
* Low tensile strength.
* Heavy – increased load on substructure.
* Not very environmentally sustainable.
* Creating moulds can be expensive and time-consuming.
What are the advantages and disadvantages of a timber frame?
Advantages:
* Lightweight
* Sustainable.
* Prefabricated – positive affect on programme.
Disadvantages:
* Fire treatment required.
What is a brick slip? And how much would one typically cost?
What buildup of a slab did you used for 8 Canada Square?
- Metal Deck with Shear studs
- RC
- Allowance for connections
- Screed
What are some examples of Replacement piling?
What is Curtain Walling?
What is a Stick system?
What is a Unitised system?
What is the typical buildup of a facade?
What was the buildup of the facade on High Holborn?
What are the advantages and disadvantages of precast?
What are the grades of waterproofing?
Why might you use a replacement or displacement pile?
