EY4106/WT5912 week11

transcript

Department of Design & Manufacturing TechnologyLecturer/Teacher: Mr. Joseph Lyster Academic Year 2011: Spring SemesterTechnical Support: Mr. Joe Murray & Mr. Richie Hennessy

Notes prepared by: Mr. Joseph Lyster

WT5912/EY4106MATERIALS AND CONSTRUCTIONWeek 11 Services & Others Areas of Interest

Department of Design & Manufacturing Technology

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Building ServicesSyllabus Outline:1. Services and External Works – Mechanical services,

electricity, wastewater treatment, sewage, etc…2. Heat and Thermal Effects In Buildings – Construction type,

Insulation, material conductivity, air tightness etc…3. Illumination In Buildings – Natural Light, glazing, LUX, heat

transfer, dwelling orientation etc…4. Sound In Buildings – Insulation etc…

Construction Studies Additional Areas

• Construction industry roles - the key people involved in creating a house• Safety on site - the importance of managing safety, accident rates, training, risk assessment,

safety statements etc.• Social impact of planning - how planning can improve (and worsen) the lives of ordinary people• Natural construction materials (NB sustainable forestry sources etc.)• Manufactured construction materials (NB waste, embodied energy etc.)• Eco’ construction materials (NB waste, embodied energy etc.)• Structural systems (concrete cavity) (NB airtightness, insulation)• Windows & doors (modern designs only e.g. triple glazed)• Energy sources: on grid energy• Structural systems (timber frame cavity) (NB airtightness, insulation)• Structural systems (Steel frame cavity) (NB airtightness, insulation)• Structural systems (straw bale) (NB airtightness, insulation)• Structural systems (SIP) (NB airtightness, insulation)• Structural systems (ICF) (NB airtightness, insulation)

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• Energy sources: off grid energy• Energy performance of houses - house design & energy consumption - looking at ordinary

houses to explore factors that impinge on energy performance (use real world examples)• Passive design (e.g. passivhaus standards)• Zero carbon housing• Building energy rating - the purpose and process - comparing examples water sources &

treatment in Ireland (use real world Irish examples)• Grey water supply (e.g. bord na mona rainsava)• Hot water supply (boiler & solar)• Drainage (municipal treatment of wastewater - use a real world example)• Drainage (additional measures for one-off treatment - e.g. puraflow/ reed bed etc.)• Air flow, ventilation, m.v.h.r• Airtightness, air pressure testing etc.• Sound - insulation details

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• Electricity - domestic wiring• The benefits of improving thermal insulation & retrofitting insulation to improve roofs• The benefits of improving thermal insulation & retrofitting insulation to improve walls.• Heat TGD L 2010 (key terms and calculations)

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Construction Studies

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T4 Recommendation

(T4, 2009)

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T4 Recommendation

(T4, 2009)

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T4 Recommendation

(T4, 2009)

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• Building Energy Rating (BER) grades the energy efficiency of a building

• A Dwelling with a high rating will save the owner/ occupier money in energy costs.

(T4, 2009)

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• New dwellings that apply for planning permission on/after 1st. January 2007.

BER required for:

• All existing buildings offered for sale or rent from 1st. January 2009.

(T4, 2009)

WT5912Building standards & energy use

100150200250300350400

1972 1979 1982 1992 2002 Current Regs2010 ?

2016 ?

Irish construction standard/year

Typical for Building Regs Part L 2005

Building Regulations2007/08

Low/ Zero Carbon

(T4, 2009)

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• Thermal insulation of the building envelope.• Heat gains through glazed openings. • Ventilation and air permeability.• Domestic hot water system and control.• Space heating control and energy required.• Lighting and internal heat gains.

(T4, 2009)

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What does BER measure?

• The BER measures energy use per square meter (floor area) of the dwelling per year.

• Measurement Unit kWh/m2/yr

Kilo watt / hour1 kWh of

electricity costs 18 cent

(T4, 2009)

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Energy Labelling Domestic Appliances

Energy labelling informs the consumer of costs.

(T4, 2009)

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• Calculated using DEAP software.

• DEAP – Dwelling Energy Assessment Procedure

BER scale (kWh/m2/yr) A1,A2,A3,B1,B2,B3 etc.

CO2 indicator (kg/m2/yr)

BER rating

(T4, 2009)

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Each full band is 75 kWh/m2/y and is indicated by a change of colour on the label.

• Each small band is indicated by a change in the grade. Example:A1 to A2 to A3

FULLBAND

(T4, 2009)

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Energy Costs and BER Cost comparasions based on average energy

costs for 2007 in a 250m2 dwelling

(T4, 2009)

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A dwelling built to the 2007/08 building regulations should achieve a:

• B or C rating

(T4, 2009)

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• No obligatory minimum standard applies.• BER must be produced by a registered BER

Assessor.• BER is valid for 10 years unless changes are made

to the building.• The BER is independant of how the occupants

behave in the building. • An advisory report must accompany a BER

certificate

(T4, 2009)

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New build:To advise owners on how to use the

features in the building to maximise energy efficiency

Existing buildings:To advise owners on the options for

upgrading of building to maximise its energy efficiency

(T4, 2009)

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Calculating the BER

Download from:http

://www.seai.ie/Your_Building/BER/BER_Assessors/Technical/DEAP/

DEAP Computer Software

(T4, 2009)

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Property address Wall Area Low energy lighting %Wall U-value Living area %Door Area Thermal mass category

Planning reference number

Door U-value Heating controls# Chimneys Factor for thermal bridging Heat emitter# Permanent vents Window Area # Central heating pumps# flues Window Description Boiler interlock# fluleless gas fires Window Frame Material Space heating fuel# Sheltered sides Window OrientationDraught lobby Window OvershadingStructure type Water storage type 2nd space heating fuelDraughtstripping Water storage volumeVentilation method Insulation typeFloor Area Solar water heating

Floor U-valueRoof AreaRoof U-value Thermostat on cylinder

MPRN (electricity meter number)

Insulation on primary pipework

2nd space heating efficiencyWater heating system fuel

Water heating system efficiency

Main space heating system efficiency

Information required for DEAP

(T4, 2009)

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1. Dimensions:• The internal dimensions of the building

envelope.• New dwellings can be measured from the

plans.• Existing buildings may need to be surveyed.

(T4, 2009)

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2. Ventilation Details

• Number of fans and vents

• Number of chimneys/flues

• Number of sheltered sides

• Presence of a draught lobby or porch.

• Method of ventilation: • Natural or Mechanical

(T4, 2009)

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3. Air Permeability• Sealing of the building envelope.• Blower door testing required on new

dwellings.• Required to be 10 m3/(h.m2) for new dwellings

@ 50 pa.

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• Ceiling/Roof U-Value4. Building elements (fabric heat losses)

• Wall U-Value

• Floor U-Value • Door & Window U-Values

• Thermal bridging factor typical 0.11 W/m2K(T4, 2009)

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5. Glazed area heat losses and gains

• Glazed area sizes. • Orientation.

• Glazed unit U-Values - Glazing - Frame

• Solar transmittance.

(T4, 2009)

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(T4, 2009)

6. Details of the hot water system

Instant or storage system.

Insulation on pipe work.

Level of Insulation on storage cylinder

Temperature and time controls.

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(T4, 2009)

7. Boiler and space heating detailsBoiler efficiency

Fuel used

Heating controls

Radiator’s or under floor heating

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(T4, 2009)

7. Boiler and space heating details contd.

Insulation on pipe work.

Temperature and time controls.

Weather compensation controls.

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(T4, 2009)

8. Renewable energy used, e.g.

• Solar photovoltaic

• Wind power

• Geothermal energy

• Solar Water heating

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9. Lighting provision in the dwelling.• The percentage of energy efficient light fittings in the dwelling.

(T4, 2009)

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The heating requirements for the dwelling will depend on:

10. Net space heat demand.

Living area is assumed to be heated to 21oC and the rest of the dwelling heated to 18oC.

• The living area %.

• The total volume.

(T4, 2009)

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11. Thermal mass category of the building ranging from:

• Thermally massive construction. e.g. concrete block with hollowcore.

• Thermally light construction e.g. timber frame

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Download the DEAP software from:http://www.seai.ie/Your_Building/BER/BER_Assessors/Technical/DEAP/

Install the software as per instructions. Use the software to do a sample rating on the sample dwelling using

the data supplied. Vary the inputs to improve the rating.

Energy rating worked example

(T4, 2009)

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(T4, 2009)

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(T4, 2009)

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(T4, 2009)

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(T4, 2009)

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Mechanical ServicesWater Systems

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Water Systems• Direct Cold Water System • Indirect Cold Water Systems• Direct Hot Water Systems• Indirect Hot Water (Vented/Un-vented)• Solar Water Heating System• Geothermal Water Heating System• Boilers:

• Oil-Fired• Gas-Fired• Solid Fuel• Wood – Chip• etc...

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•Direct Cold Water System

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•Indirect Cold Water System

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WT5912•Indirect Hot Water System

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•Water Cistern/Tank

WT5912•Indirect Hot Water System with Two Pipe Radiator System

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WT5912•Two Pipe Radiator System

WT5912•Solar/Woodchip

WT5912•Solar Hot Water System with Two Pipe Radiator System

WT5912•Services

How the evacuated tube works;Sunlight enters through the outer glass tube, hits the absorber – where energy is converted to heatHeat is transferred to liquid inside inner tube- vacuum between tubes prevents heat loss.The hot liquid rises to the top of the copper tube where it transfers heat to the pipework coming from the cylinder, this pumps through the cylinder heating water.The liquid is cooled as it transfers the heat and flows back down to be reheated.Cylinder Specifications.The cylinder is insulated to meet the building regs in TGD L1.4.4.2 with 75mm thick CFC free factory applied insulation and has its pipes coming from the tank insulated to 1m from the tank.The cylinder has, as needed by 1.4.3.3 of TGD L, a thermostat which can turn off supply of heat when desired storage temperature is reached.It will be fitted by a qualified person as required by 1.2.7.Back up Boiler.The back up boiler is an electric boiler which will be powered by our windmill in ideal circumstances, it will also be connected to the grid as an extra back up and also as the windmill is required to be connected to the grid.

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WT5912•Wastewater Systems

WT5912•Pipe Laying

WT5912•Backfill/Positioning/Rodding Eye

WT5912•Manhole

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WT5912•Percolation Area

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• Wastewater is removed from the dwelling by a system of pipe work which carries the waste fluids away from the appliances.

• Purpose of pipe work – Transport fluids, Control leakage, Resist deposits of solids, Resist blockages

• Waste pipes are commonly - Ø32mm for hand basins, Ø40mm for bath/shower, Ø100mm from toilet (w.c)

• Ø100mm for discharge stack• Ø40mm/Ø32mm pipes from the showers and sinks have a slope of

18/90mm/m, with a max length of 3 metres to the stack • Ø100mm pipes from the toilets with a slope of 9mm/m, with a max length

of 6 metres to the stack, a macerator unit will be used if the distance exceeds 6 metres.

• Two hundred mm minimum centre line radius at the bottom of the stack for a gradual turn.

• The stack (Ø100mm) has to be 900mm minimum above the window in this case as it is within three metres of the window.

Wastewater

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• Drainage pipes are laid in a bed of 10mm aggregate covered in 40mm of crushed stone and the trench is backfilled with the excavated clay. 300mm cover should be provided to protect the pipe.

• Soak pit used to take the grey water from the kitchen sink, dishwasher and the washing machine.

• Use of “P” traps to prevent odours entering the house, with a seal depth of 75mm minimum.

• Air admittance valve can be used to combat incorrect installation and design by providing a source of air when a vacuum may be generated and syphonage can occur.

• A wastewater Puraflo Liquid Effluent Treatment System can be easily integrated with a new or even existing septic tank and is constructed to meet building regulations.

• Wastewater flows from the home into a watertight primary/ septic tank

Wastewater

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• Capacity of the tank is calculated using the formula C = (180P+2000)• The solids settle and the liquid effluent flows by gravity into a pumping chamber. • The pumping chamber is fitted at least 0.5m from the septic tank. The septic

tank outlet is connected to the pumping chamber using a 100mm diameter pipe at a gradient of 1 in 100. The peat filter is located 7 metres from the septic tank.

• The liquid effluent is pumped intermittently into the Puraflo modules and distributed evenly onto the biofibrous peat filter.

• A combination of biological, chemical and physical processes treat the wastewater as it filters through the biofibrous peat in the modules.

• Treated liquid emerges from the Puraflo unit for dispersal into the ground through a soil polishing filter.

• High level of treatment achieved, energy efficient, low running costs, consistent operational efficiency, minimal maintenance required, odour-free wastewater treatment, Bord na Móna warranty, service agreements and call-out service, alarm system included if the level of waste water in the pumping chamber becomes to high and it is installed by Bord na Móna Environmental Ltd.

Bord Na Mona Puraflo System

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(Hickey, 2006)

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• A unit for a single house has two modules of total area 5m2, which can serve up to 6 people.

• An area is prepared and levelled to create an even surface on which to place concrete blocks and lintels to support the modules. Broken stone approximately 25–50mm is filled level with the top of the concrete blocks and lintels over are placed over this area to a depth of 200mm approx.

• I chose this as it only uses an intermittent pump so it only pumps the water on a “needed basis”, unlike other new systems which constantly need a power supply, this saves on the cost and usage of electricity and a power loss would not disrupt the system like it could do with others.

• The Puraflo system is Irish Agrément certified & EPA compliant.

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(Hickey, 2006)

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Traps/Pipes

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Soak Pit

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Manhole

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Biocycle Treatment

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• Mechanical Aeration Waste Water Treatment System• Given the layout and considerations of the dwelling . I decided to go with a

12,000 litre Biocycle treatment unit. This system is highly efficient and has a long de-sludge interval period.

• It is environmental and user friendly.• The unit will cater for all foul waste included waster containing household

detergent. These detergents do not affect the functionality of the unit.• The unit consists of 4 chambers

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1 Primary- Big chamber to allow for retention of sludge. Sludge broke down with anaerobic bacteria.2 Aeration- Aerobic bacteria break down the effluent by a culture of bacteria within a process known as submerged aerated biological filtration. Oxygen, to support the degradation processes, is introduced by a small air pump. 3 Clarification- The clarification chamber is designed to provide quiescent conditions allowing any bacterial flocs remaining in the effluent to settle out.4 Pump- The large pump chamber allows the treated effluent to be stored before it is pumped to the polishing filter or surface irrigation system. The pump is operated intermittently to ensure low energy usage.

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Advantages: EN 12566-3 accredited (new standard for wastewater treatment systems) 97.5% reduction in BOD5 (Biological Oxygen Demand) 97% reduction in S.S. (Suspended Solids) Unrivalled sludge storage Low electrical running costs Life span in excess of 60 years

• Brac Greywater recycling system RGE – 250 This system is perfectly designed for a family of 5. The RGW-250 is the popular tank, designed for homes with up to 6 people who want to save money on their water bill, while helping the environment.• How it works... Greywater from showers, baths, sinks and the washing machine go directly into the Brac Systems holding tank. Here the water is filtered and ready for delivery to toilets.• Advantages Two thirds of our water is used to shower, bathe and do laundry; another third is used to flush the toilet. By reusing some water to flush toilets, the Brac System saves 35 to 40% of a household’s annual water consumption. Extends a household’s water supply, thus lessening its’ impact on the environment. Reduces the risk of water shortages in hot climates where wells tend to dry up.

Biocycle Treatment

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Biocycle Treatment

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(Hickey, 2006)

Biocycle Treatment

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The U-Value question is not a compulsory question but it is contained within the options question, usually Question 5 on the paper.The question generally contains 3 parts – A, B, and C.A. Generally requires the visual manipulation (Section view sketch +Labelling!!!), the tabulation of data in logical and functional order, and the calculation of a U-Value for the material data given.B. There are variations to this part. The typical variations are the calculation of oil used with subsequent calculation of cost loss, the sizing of insulation omitted from the initial question or insulation required achieved the required U-value standard, the size of glazing units with their impact on the U-Value performance, and there are variations to the afore mentioned but nothing too different.C. This part generally requires a recommendation to improve or show the difference between different systems presented in the question. Sketches and notes usually apply and it serves to show you have an understanding for the area at hand.

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•The U-Value question can require work but it is as hard as you make it!!! It is an achievable question that with a bit of practice can be attempted by all pupils.•It is a step by step style question with the variation on part B and C of the question that can also be well prepared as there are about 4 different variations that can be asked of you in these part. •The question requires the understanding of U-Values and the ability of students to use the data correctly to show visual, arithmetic, data comprehension/manipulation/tabulation and procedural capabilities.

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Do not be intimidated by the mathematical problems presented in this question. The application of simple arithmetic is all that is required i.e. - / + / ÷ / x

You will need a calculator as decimalisation is required, so be competent and comfortable in the use of your calculator.

Always re-check your calculations!!! Also do not be intimidated by the Units that apply to the

different variants. Once you have learnt them and consistently use them correctly whilst practising the question it should not be a problem. If you don’t apply the unit to the calculations you will lose valuable marks!!

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Content: What are we calculating? In the case of this question the area of U-Values apply to the

external envelope of the building i.e. The external wall structure, the foundation structure, and the roof structure.

External wall structure: Block cavity construction and timberframe construction,

glazing etc... Roof Structure: Flat and Pitched with Ceiling, etc...

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U-Values are essentially the measure of heat lost through the fabric of the buildings external envelope.

Under current building regulations 2007 Technical Guidance Document L on The Conservation of Fuel and Energy it is stated that buildings by standard should be built to achieve a U-value of at least 0.220 W/m²⁰K.

This is achieved by adhering to the building codes and standards where sustainability and material selection combined with an efficient construction process all serve to limit the impact on the environment.

When we lose heat we lose money€€€€ but most concerning is that to replace heat and energy loss we expend further energy resources creating a greater demand and inturn showing further disrespect for our environment.

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Typical Heat Loss Percentages Typical Heat Loss Percentages

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Aim: The aim is to make you the student aware of the relevant U-values that can be achieved from a combination of materials that form the external envelope of a building.

In doing so you will begin to realise the difference between materials and their ability to resist heat/energy loss. The influence of insulation will be a key factor and it is advised that you take time to investigate different insulation products.

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In terms of the question what should we know? The Materials Presented i.e. block, timber, etc. 1. U-Value =Thermal Transmittance (W/m² ⁰k) 2. R = Resistance (m² ⁰k/W) 3. r = Resistivity N/A 4. k = Conductivity (W/m⁰k) 5. T = Thickness (m = metres) W = Watts, m = metres, ⁰k = degree Kelvin ( or alternatively ⁰C

= degree Celsius)

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Terms & Definitions: Definitions are very important and they are often over looked by students. In understanding a definition you can make sense of the data presented to you in the question.

It will enable you to visualise the process alot easier and understand the thermal data difference between relevant materials so you can form a guess estimate by where you can measure the outcome of your work through out the question. It is basically a level of common sense that will serve to build your competence in the question.

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Thermal Transmittance (U-Value) Unit Value = W/m² ⁰k Definition: A measure of the rate at which heat passes through

a particular element of a building when unit temperature difference is maintained between the ambient air temperatures on each side. The U-Value takes into account the resistances of various materials, the surface resistances and the cavity.

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Thermal Resistance (R) Unit Value = m² ⁰k/W Definition: A measure of a materials ability to resist the flow of

heat energy. The higher the R-Value the greater the resistance of the material.

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Thermal Conductivity (k) Unit Value = W/m⁰k Definition: A measure of a materials ability to conduct heat

energy. When comparing insulation products the k-value is used as the

comparative benchmark as the lesser the k-value the better the product in terms of performance. However the constituents of the insulation material is always the greatest debate in terms of its availability, embodied energy and impact on the environment.

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Example of a typical Question: As Presented

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Breakdown.

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Step 1: Make a Sketch of the information given and label !!!

Step 2: Tabulate all data as shown

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Step 2: Continued. When filling in the material thickness column it is important

that you convert the data to metres (m) as the question gives it in millimetres (mm). This catches alot of students out so ensure to do this before you fill the table in.

Example: Block = 100mm, so 100÷1000= 0.1m, this is the value that is input into the table. You divide all thickness and width data by 1000 to convert from mm to m.

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Step 3: Calculations Formula 1: R = T/k, you may have to manipulate this formula to find

data so here is a tip if switching formula’s around confuses you!!! R²=T⁸/k⁴, note the numbers in the power position. 2 = 8/4, so if i

wanted to find T then 8=4x2 (T=k x R) and if you follow the numbers in the power position as shown below then you can see how this can guide you correctly. T⁸=k⁴xR² (8=4x2). This is just a simple method to avoid confusion.

Remember R = Resistance, k= Conductivity, and T = Thickness (m) Also in the event of a resistivity value being given you may apply this

formula, “remember resistivity = r”, R = T x r

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Step 3: Continued. Once the R- Column is complete the you get the sum of that

column to calculate the R- total. Step 4: Calculating U-Value U-Value = 1/R total Indicate all Unit values!!!

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To attempt the part B questions please refer to the exam solutions for guidance as follows.

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Mr.J Lyster Study Purposes Only

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Part A – The Sketch

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Part A – The Table + U-Value Calculation

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Part B – Heat Loss, Oil and Cost Loss

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Part C - Insulation

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Part C - Insulation

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Part A – The Sketch

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Part A – The Table + U-Value Calculation

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Part B – Heat Loss, Oil, and Cost Loss

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Part C – Interstitial Condensation

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Part A – This time no sketch required.

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Part B – Design Considerations

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Part A. No table or sketch required. Apply Calculations from the information given!!

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Part B

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Part C.

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Part A

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Part B

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Part C

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Part A

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Part B

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Mr.J Lyster Study Purposes Only

Part C

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Part A

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Part B

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Orientation

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Notes on Glazing

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Orientation

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Glazing etc...

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Room Layout & Solar Gain

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Thermal Mass/Space Heating

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Materials etc...

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Materials etc...

WT5912Components of Electrical System

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Ring Main

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Radial Lighting Control

WT5912Distribution Board/Fuse Box

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• MHRV-popular means of dealing with dampness and avoidable heat loss• Cost effective, health beneficial and an efficient solution to saving energy• MHRV works in the following way:

1. First set of ducts (red) collect moist, stale air from hotspots2. Stale contaminated air travels through the HRV unit and released outdoors3. Second set of ducts (blue) takes clean fresh air from outside4. Both air streams pass through heat transfer exchanger where heat from the stale

air is used to warm the fresh incoming air. Air streams do not intersect. HRV unit retains up to 95% of the heat emitted from the warm stale air

5. Above processes allow for clean filtered air to be distributed throughout the building• MHRV offers year round comfort and has the ability to keep living areas at a warm constant temperature• Health benefits: alleviate symptoms of asthma, cold and hay-fever by removing airborne pollution and irritants• MHRV can also extract smoke and cooking odours• Requires minimum maintenance and leads to increased security and noise reduction as well as aesthetic enhancement• New MHRV systems operate at 95% efficiency compared to 65% efficiency of older systems

Mechanical Heat Recovery Ventilation (MHRV)

WT5912Mechanical Heat Recovery Ventilation (MHRV)

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Rainwater Harvesting

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Grey Water Harvesting

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Rain Water/Grey Water Harvesting

(Hickey 2006)

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Tank Sizing

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EY4106/WT5912 week11

Education