What is a BER?

 A BER (Building Energy Rating) is a grade given to a building, which confirms the energy performance of that building. The BER is similar to the energy rating of an electrical appliance with an ‘A1’ rating being the most efficient and ‘G’ least efficient. The BER is produced by a qualified BER Assessor on completion of the building using SEI approved procedures and software. The resultant BER is affected by the building dimensions, ventilation, windows and glazing, insulation levels, living areas sizes and boiler efficiency.

What is BER Assessor?

Why do I need a BER?

Under current European (EU) Law, a building owner in Ireland is required to provide a BER to prospective buyers and tenants for new dwellings in which planning permission was applied for on or after 1st January 2007.
The requirements for BERs on new and existing non-domestic buildings will also be implemented over the next two years.

What are the implementation dates for buildings requiring a BER?

The following outlines the time schedule for which BERs will become mandatory:

• New dwellings: All new dwellings for which planning permission was applied for on or after 1st January 2007. Transitional BER exemptions will apply to new dwellings for which planning permission is applied on or before 31st December 2006, where the new dwellings involved are substantially completed on or before 30th June 2008.
• New Non-Domestic Buildings: All non-domestic dwellings for which planning permission was applied for on or after 1st July 2008. Transitional BER exemptions will apply to new non-domestic buildings for which planning permission is applied on or before 30th June 2008 provided the new non-domestic buildings involved are substantially completed by 30th June 2010.
• Existing Buildings: All existing buildings (dwellings and other buildings) when offered for sale or letting on or after 1st January 2009.

What is a Provisional BER Certificate?

A Provisional BER Certificate can be produced for dwellings which are sold off the plans. It is a requirement for the seller of the dwelling to produce a provisional BER Certificate to potential buyers. The BER is based on pre-construction plans and specifications. The seller must provide a new BER Certificate to the buyer on completion of the dwelling. An advisory report is also provided to each client with each BER Certificate.

Provisional BERs can be used as a guidance tool for those considering building a new home, to achieve the best possible energy rating. To improve the BER of a dwelling the person building the house may consider some of the following:

• insulating the hot water cylinder and pipework;
• increasing the insulation in the walls/ attic/floor;
• installing advanced energy efficient glazing;
• replacing an old or inefficient boiler with a more efficient boiler;
• installing modern heating controls;
• installing certain types of renewable energy heating systems.

How do Solar Panels Work?

The most common type of solar water heating system used in Ireland is the indirect system. A liquid mixture of water and glycol (anti-freeze) passes through a meandering copper tube within the solar panel (solar collector) which absorbs solar radiation. The heated liquid leaves the solar panel through insulated copper pipework and enters the domestic hot water cylinder. Within the cylinder the liquid runs through a copper coil which heats the surrounding water in the cylinder. The water/glycol mixture never makes contact with hot water in the cylinder which is used for domestic services. The liquid in the coil then leaves the cylinder and is pumped back up the solar panel to be reheated.

A properly designed and installed solar water heating system can provide between 30 – 70% of the domestic hot water needs over the year.

A supplementary heating source, such as an oil or gas combi boiler, biomass boiler or heat pump, is often used to heat the domestic water to the required temperature, when there is little solar radiation.

What types of Solar Water Heating Panels (Collector) are there?

  The most common types of solar collectors used in Ireland are as follows: 

• Flat plate - This type of collector is made up of a flat absorber plate which absorbs radiation from the sun. The absorbed radiation is transferred to a heat transfer liquid which is run in narrow meandering tubes connected to the absorber plate. This fluid carries the heat to the hot water storage cylinder where the heat is transferred to the stored liquid. The whole assembly will be contained in an insulated weather proof housing.

There are many variants of flat plate collector but they essential fall into two categories:

• Glazed – Used to retain heat and reduce thermal loss due in cold weather
• Unglazed – Used normally to heat swimming pools in summer weather.

Vacuum Tube – The two types of vacuum tube solar collectors used in Ireland are as follows:
Heat Pipe - A heat pipe is essentially a copper pipe, within the evacuated tube, containing a special fluid which evaporates when heated, even at low temperatures. When the fluid evaporates, the vapour rises and transfers the heat to the solar system’s primary circuit water by means of a heat exchanger at the top of the tube. As the primary circuit water takes the heat from the vapour in the tube, the vapour then condenses and returns to liquid form. The liquid returns back down the tube under gravity and the cycle is repeated.

The high vacuum results in an almost total elimination of convection and conduction losses from the absorber.

Primary Fluid Collectors – This type of evacuated tube is similar to the heat pipe assembly, with the main difference being the heat pipe is replaced with two concentric copper pipes. The heat transfer liquid flows through the space between the outer and inner pipes, picking up heat from the absorber plate (which is connected to the outer pipe) and back through the inner pipe.

The inner pipe is normally 10mm in diameter, with the outer one 15mm. The outer one is also sealed at bottom end. Each of the 10mm pipes in an evacuated tube assembly are connected to a 22mm copper header, with the 15mm pipes to a separate header.

How do Heat Pumps Work?

The two most common types of heat pumps are:

• Ground (Geothermal) source heat pump
• Air source heat pump

Ground source – This type of heat pump takes the heat that is stored naturally in the ground to provide domestic hot water and space heating. They can also be used as heat dumps, transferring unwanted heat to the ground outside.

A geothermal heat pump system consists of indoor heat pump equipment, a ground loop, and a flow centre to connect the indoor and outdoor equipment. The geothermal heat pump can be compared to a refrigerator in reverse. It takes the heat from one location, which in the ground, and places it in another location, which is the building for which the energy is required for. The ground loop, which is installed beneath the earth’s surface, allows the exchange of heat between the earth and the heat pump.

Geothermal heat pumps can be operated in an open or closed loop. The open loop system takes water from the source of the geothermal heat (eg. a well), extracts the heat, and re-circulates it back into the well as cold water. The closed loop uses water and an antifreeze solution in a ground loop of pipe to draw the heat from the well.

Ground loops can be installed in a vertical well or a horizontal loop. Vertical wells are usually more expensive, due to the cost associated with boring the well, and are used where space is limited. The length of loop pipe required will vary with soil type, loop configuration, and system capacity.

Air source – An air source heat pump uses the outside air as a heat source, when heating is required, and as a heat sink when cooling is required. They cost less to install than a ground source heat pump but are less efficient when the outside temperature drops below freezing. `

  A heat pump uses the refrigeration process and transfers low temperature energy from the outside air to a refrigeration loop, compresses the refrigerant to a high temperature and transfers this heat to the hot water and space heating distribution system.