Construction Technology and Environmental Services Flashcards
What do you need to consider when specifying cladding?
1) Whether Synergy have PI Cover to specify cladding.
2) Consider the following characteristics:
a. Fire Protection
b. Moisture and movement,
c. Product Performance,
d. Durability,
e. Service life,
f. Impact on adjacent surfaces,
g. Structural limitations of frame.
3) If they do, the following considerations need to be made, where are the fire breaks going to be installed? Is the cladding non-combustible A1, A2 rated? Does the cladding require ventilation to eradicate moisture build-up? Does it comply with Part B?
What are the benefits of timber framed construction, with regards to sustainability?
Timber absorbs carbon and therefore is a more environmentally friendly material.
How can we determine that cladding is safe? What to consider?
- Fire engineering input is recommended for all properties above and below 18m.
- Part B and Approved Document B. Must resist the spread of fire over walls.
- Building Regulation 7 was expanded to restrict use of combustible materials short of Euroclass A2-s1.
- A modern non-load-bearing façade system has three main sections: the external cladding, thermal insulation and the backing wall. All three parts may promote fire spread.
- BR 135 assessment - Testing products in relation to combustibility.
So can you tell what you know about Aluminium composite materials (ACM’s)?
They are attached to the primary structure of a building to form non-structural external surfaces. Are commonly used as a form of rainscreen. Consists of two skins of aluminium bond to a lightweight core or materials such as polyethylene. During a fire, the panels can delaminate exposing the core material which is combustible. The potential issues with rain screens clad in materials such as combustible ACM panels, for instance, include a propensity for rapid external fire spread, which can be accelerated by a ventilated cavity acting as a chimney, and fire compartments that cross over one another. In Grenfell, ACM classing was used and it contributed to the rapid spread of the fire.
What types of Fire Breaks are used for external wall cladding?
Intumescent ventilated fire barrier will quickly expand to seal off the cavity to prevent the spread of fire.
How to identify a composite panel?
ACM can be visually identified at the cut edge by a plastic core sandwiched between two wafer-thin skins of metal. Although such identification is tricky with folded- or tray-profile panels, ACM usually produces a sharp mitred edge in contrast to the shallower radius of a folded, solid-metal panel.
What are the different types of Guarantees and how can it benefit the Client?
Guarantee - Insurance backed guarantee (This means that if the company goes into administration, then the insurance will cover this). Manufacturers Guarantee (NB You must ensure the company has longevity).
What is the difference between a warranty and a guarantee?
1) Guarantee is a promise that attests the quality and durability of a product or service.
2) A warranty is usually a written guarantee and holds the manufacturer or installer responsible for repair or replacement for defective products. Legally binding assurance or promise.
Insurance backed - Basically means if the contractor was to cease trading then the insurance would honour to contractors guarantee up until the expiry of the guarantee.
What are Structurally insulated panels?
These are referred to as SIP panels. They are manufactured off site and foam insulation is installed between two structural skins of oriental stand board (OSB) or other skins in factory controlled conditions. Depending on the scale, the whole building can be constructed within a week for a typical house.
What are the benefits of Structurally Insulated Panels (SIP)?
It has the following benefits:
- Energy efficient strong pre-insulated structure
- Excellent U-Values as low as 0.13
- Typical house erected in 5-7 days, including the roof.
- Increased usable roof space
- High levels of air tightness
- Reduced cold bridging
- 7x stronger than timber frame
- 3x stronger than brick & block
- Cost effective with savings on labour
- Naturally greener than other build types
MMC (Modern Methods of Construction) Advantages
Advantages
- Weather is not an issue,
- Quick on site installation
- Management of timelines to allow simultaneous working,
- Quality control,
- Less safety concerns in controlled environments,
- Reduction of waste,
- Airtight commercial buildings.
MMC (Modern Methods of Construction) disadvantages.
Disadvantage
- Suitability depends on location
- accessibility etc for large vehicles delivering,
- Changes in design and plans are not possible once the project starts,
- demands extreme detailed planning,
- Customisation in modular construction is limited,
Demands more communication between on site and off site workers.
Are you familiar with term Thermally broken and tell me more about this term?
Non thermally broken and thermally broken windows - New technology, reduces condensation and cold bridging. The thermal break in aluminium is a barrier that breaks the aluminium to aluminium contact from the inside to the outside of the window.
Why do they use argon in windows?
Argon gas is an inert gas, which means that it isn’t prone to undesirable chemical reactions. The gas is considerably denser than air and has a much lower thermal conductivity, about a third less than air. Helps stop heat transfer. The glazing gap creates a thermal gap between the conductive element – glass.
Why would you specify aluminium over say PVC?
Aluminium is a recyclable material so it more environmentally friendly. It also has a longer lifespan in commercial buildings and can be powder coated to suit the clients needs.
