Heating

Heating to the following school rooms and functional spaces may be required to maintain an in room ambient temperature between 19 °C and 22 °C:

• All teaching spaces
• Libraries and resource centres
• Administration and staff office areas

Electric heating must be preferred over gas heating. Where gas heating is considered, it must be approved by SINSW Sustainability.

The heating services must meet the requirements of Section J of the BCA, and may include any or all of the following:

• Convection heating by flued gas convectors (requires approval)
• Convection or warm air heating through ductwork and terminal air fittings
• Radiant heating using flued radiant gas heaters (requires approval)
• Reverse cycle operation of air conditioning
• Heating incorporated into evaporative cooling units (i.e heating, ventilation and cooling units)
• Hydronic radiant heaters
• In slab heating (requires a slab and screed, so a life cycle costing must be undertaken before this is considered).

Project Heating Strategy
 

A heating strategy must developed for each project to ascertain and set out the most appropriate heating system or systems to be included in the project.

The need for active heating equipment must be minimised by employing passive sustainable design principles (eg. Solar heat gain, thermal mass storage etc).  Where active heating systems are required, they must be designed from a “Whole of Life” perspective to provide:

• Value for money
• fitness for purpose
• long term reliability
• minimal maintenance requirements
• low maintenance costs

Specifically heating equipment must:

• Support sustainable design principles including reducing energy consumption and long term carbon emissons
• Be accessible and serviceable - easy to maintain with minimal impact on school use when maintenance is being performed
• Be vandal and tamper resistant

Head designer or equivalent must ensure effective co-ordination between disciplines.

At sketch plan stage: 

• Locate and estimate the size of the plant rooms in consultation with the architect.
• Design appropriate heating system.
• Co-ordinate with other disciplines for provision of water supply, tundish for drain, power supply, structural openings, etc, associated with heating system.
• Prepare a Whole of Life, life cycle cost analysis as required.
• Prepare estimates as required.

Equipment Life-Cycle Cost Calculations

For new schools and when replacing or updating major heating components, a simple life-cycle cost should be calculated. This must be based on Life Cycle Cost considerations following over a period of time, e.g 20 years and/ or the life of the asset.

As part of the Whole of Life analysis, the life cycle costs must consider the following:

• Capital cost of the asset
• Capital cost of any supporting/ enclosing structure (plant rooms/ platforms)and/ or servicing equipment (eg access ladders etc)
• Multi-service integration and interface - provision (and costs) of any supporting services (eg power, gas tanks etc).
• Reticulation of ductwork, flues, piping and of cables, if applicable
• Resource (water/ power/ gas etc) consumption costs. Based on; 1 year, 5 years, 10 years and / or 20 years.
• Maintenance required and cost of this maintenance;
• Frequency, nature and costs of capital upgrades needed over the life of the asset to maintain fitness for purpose
• Cost of disposing of the asset or its components.

The following must also be considered:

• Provision for expansion of plant and equipment (if a likely possibility)
• Life span of the asset;
• Accessibility for servicing

Refer to DG / WHOLE OF LIFE

Design Conditions : Interior Spaces
Winter                          19° CDB +2° C

• Noise criteria        
  • NR 35 within the conditioned space
  • 55dB(A) at 1 metre from Plant Room/ enclosure

Refer to DG / ACOUSTICS

Select the appropriate heating solution for the individual school to meet the following criteria:

• Must comply with all BCA requirements.
• Suit the areas served.
• Represent the best Value for Money in the Whole of Life assessment.

Flued induced draft horizontal tube overhead radiant gas heaters

Could be effective in certain situations such as:

• large spaces and/ or spaces with large volumes (must have minimum clear ceiling height of 3.5 metres)
• areas with high air changes

Ducted warm air heating

• Requires high volume of outside make up air
• May be suitable where flame sources or heaters with very hot components in an environment with dust and fumes could create a flammable or combustible environment

Reverse cycle air conditioners

• Use only where air conditioning is installed for air cooling
• Use only when convection or radiant gas heating is not possible
• In areas of extreme temperature ensure the selected equipment can perform on cold winter mornings when maximum heating is needed

Heating Cooling and Ventilation Units

• Heating can also be incorporated into evaporative cooling units to form a heating, ventilation and cooling unit
• Consider only when evaporative cooling is installed

Hydronic radiant heating

In cold climates it can be an economical and highly effective form of central heating.

Involves heating water in a boiler, and then pumping it through piping to panel radiators or convectors positioned in rooms.  Heat is transferred directly from these to the room air.  In-slab (‘floor coil’) systems are also available.

• Provide individual control valves to each panel to allow individual rooms or zones to be heated independently, enabling running costs to be substantially lowered.
• Panel radiators can provide effective heating for rooms with higher ceilings
• Silent radiant heat distribution have no air movement making them suitable where dust and fumes could create a flammable or combustible environment.
• Offer flexibility as further radiators or convectors can be added to a system as required, provided there is adequate boiler capacity.
• Generally have a good response time
• Low maintenance requirements.

In slab heating

• In slab radiant heating can be very effective as it uses the thermal mass of the floor to heat air in the occupied zone at low level;
• Slow response time
• These systems require a slab, screed topping and under slab insulation.  The Life Cycle Costing shall be undertaken before this is considered.
• In slab and space temperature sensors are required for control of systems.
• Where used in reverse cycle mode in cooling, dew point sensors are require to prevent condensation on floor surface.