Low Energy Building Design

Vasili GordeyevMark Gilroy Susannah HoggRuaridh DeansDale FindlaySean Hamill

Type of room Area per person Total area

Lecture room 1m2 1840m2

Tutorial room 1.8m2 290m2

Meeting room 2m2 120m2

Large meeting room 2.5m2 200m2

Computer lab 2.7m2 540m2

Staff/Postgraduate offices 6m2 1800m2

Brief and site analysis

• 2000 Person maximum capacity low energy building on existing James Weir site

• Approximate total 5000m2 excluding foyer, museum, café, toilets.• Provide disabled access and cyclist facilities• Climate conditions:• 1100 average annual rainfall• 3.4hours average daily sunlight(varies 0.8 to 6.1)

• Site on an approximately 5° angle south facing slope• Bounded by buildings on West and South sides

• Room capacities:

Key considerations for our design

•Focus on energy consumption reduction Increasing thermal comfort for occupants while reducing energy demands Aim to provide an innovative and high performing building envelope

•Incorporating renewable technologies• Lowering carbon footprint of building through on-site generation

•Consideration of embodied carbon Assessing overall lifecycle through use of locally sourced, reclaimed or recycled

materials• Reduction of carbon emissions to a minimum• Waste reduction/recycling during construction and building life

•Efficient building design Utilisation of sloped ground, sunlight, Using guidance of BREEAM, LEED, etc

• Sensitive Design• Integrate architecturally with the adjacent buildings of Thomas Graham

(predominantly glass) and Royal College (sandstone)

Case Study: Elizabeth Fry Building, University of East Anglia

•Floor area: 3250m2• Well insulated building envelope; including triple glazing, double-skin blockwork walls and nylon wall ties to reduce thermal bridging•Mid-pane perforated venetian blinds• Exposed structural ceilings of ventilated hollowcore slabs providing ventilation and heat recovery from internal gains• Additional heating provided from three domestic size boilers (typically requiring only one)• Total energy consumption of approximately 341,250kWh/year• 70% occupant comfort satisfaction

Case Study 2 – Manchester Metropolitan University’s new Business School

• £67M development•23000m2 building •To cater for 5000 students and 450 staff•Includes: lecture theatres; seminar rooms; meeting rooms; social learning; IT drop-in zones; and staff offices•3 separate blocks adjoined with covered atriums with inter connecting bridges.

•Air handing plant with an energy•2500m2 photovoltaic cells on the south facing roof•Ground source heat pumps•Heat exchangers and heat pumps•Innovative ‘Coolslab’ concrete •Curtain glass wall has a diachronic filter incorporated•Sedum roof has been planted

In situ concrete topping

Reinforcement

Polystyrene voidformers

Omnia plankCast in pipework

‘Coolslab’•Innovative system•Combines the thermal mass of the concrete with a water cooling system•90m deep boreholes draw cold groundwater into the system•Draws out excess heat, allowing the rooms to remain at an ambient temperature

Reclaimed Steel

•Easily available•Low Environmental Impact •Large Cost Saving•Locally Sourced• Greater spans • Less overbearing structure

Sandstone•Locally available material•Traditionally used throughout Glasgow•Easily reclaimable from derelict sites

Consideration of materials

Energy Reduction Techniques: Utilizing available daylight

Bridgewater House, Bristol Indianapolis Airport TerminalVancouver Clinic

• Central atrium forming a corridor ‘spine’ drawing natural light into the building

• Eliminates need for artificial lighting in these highly-used areas

• Provides a harmonious environment to occupants

• Lower level corridors can be dark, requiring artificial lighting• Requires larger area (e.g. to be heated), of which upper levels become void areas

Utilizing available daylight in rooms through daylighting techniques

•Ideally maximise South and North exposures, minimise East & West exposures• Balance between admission of light and thermal issues• Avoid glare•Daylight redistribution devices• Can consist of large horizontal element (lightshelves) or louvered system• Used in combination with daylight response electric lighting controls

Birnbeck Island Concert Hall• Passive dynamic façade louvered system• Solar irradiance falling on a thermo-hydraulic element rotates fin and controls solar gains • Avoids unreliability of electronically or manually operated façade systems

Energy Production Technologies – Building-Integrated solar devices

Bunn International Centre (ICC) Solar Array, Georgetown University

George Thomas Building PV Atrium, University of Southampton

• Offset initial costs• Hybrid PV/solar thermal systems• Thin-film flexible solar modules can be semi-transparent • Power generated directly related to PV active area and irradiance• Performance monitoring• Regular maintenance required• Must be designed for snow and wind loads (e.g. angles to shed snow)• Generous feed-in tariffs

Rainwater Harvesting

Advantages• Regarded as a ‘clean’ source• Since large proportion of water used is for

flushing there is a high potential for saving• Lifespan of tank can exceed 100 years• Estimated that 2.7 million liters can be

collected per year based on the current roof area

Disadvantages• Increases the carbon footprint and embodied

carbon

Why not greywater recycling? • Potential concern with water cleanliness• Little greywater is generated in these types of

buildings• Long payback period

Birmingham Library

Renewable Heating Sources – Combined Heat and Power (CHP)

• Process combining electricity and heat. • Fuel Source; natural gas, propane, fuel oil,

coal, wood chips, biogas or other biomass materials.

• Environmentally friendly, especially if using biogas or biomass materials, helping reduce buildings carbon emissions and cost.

• Dedicated CHP unit. Steam driven to produce electricity and heat water supply. Small CHP unit ideal for building design.

• Disadvantages – High capital cost, noise pollution, high maintenance, complex to adjust, produces more heat than required in summer months.

Ground Source/Geothermal techniques

• Horizontal or Vertical coils. Heat source placed in soil (5m). Soil temperature constant due to isolation from weather effects.

• Horizontal loops dug into trenches deeper than frost line (1-1.5m)

• Vertical loop field constructed from pipes running vertically to a depth of (100-200m).

• Geological investigation needed. • Vertical GSHP more suitable - requires small

land area, park space in front possible for use, temperature of soil doesn’t depend on season, low maintenance and less pipe needed.

• Disadvantages - with deep installation chance of encountering rock formations, prone to linking, rail disturbance from neighbouring rail network – encountered on our site

Energy Piles

• Similar processes to GSHP, except coils are down through piles foundations of building. Foundation piles can be adapted to hardness of geothermal energy.

• Pipes are plastic and readily accommodated within the pile reinforcement cages. System is reversible and can be operated at best efficiency between seasons. Anti-freeze also circulated through closed pipe work system. Concrete forming the piles is an ideal energy transfer medium.

• Advantages – no local emissions or pollution, no external vents or flues, 50% reduction in plant-room space requirement, 7 BREEAM points potential.

• Already reported successful in numerous colleges and academy's e.g. Keble College, Oxford.

• Inclined PV roof in South-East direction• Daylighting techniques included in glazed areas and central corridor atrium• Rainwater recycling

Generating ideas for design

Layout- Considering flow of building

Main door

Museum display areas

Stair wells

Lift

ToiletsKitchen and cafe

Schedule of further work

Action Week

1 2 3 4 5 6 7 8 9 10 11

Case Studies

Idea generation

Initial designs

Research particular systems

Refining/rejecting ideas

Designing building

Data generation (modelling)

Refining design

Writing webpage