Technical Guidance Documents

The Technical Guidance Documents (TGD) are published to accompany the Building Regulations 1997 – 2012 and outline how the requirements of the regulations can be achieved in practice. They apply to buildings constructed since 1 June 1992.

There are 12 parts to the guidance and this blog summarises the key requirements of each part.

The guidance documents can be found here.

Figure 1: Technical Guidance Document Part A - Structure

Image from Department of Housing, Planning and Local Government

Part A Structure

Buildings should be constructed so that actions on the building are transmitted to the ground safely and that ground movement will not impair the stability of the building.

Buildings should have adequate supports so that in case of a collapse, it doesn’t cause disproportionate damage.

For more information on foundations and floors, see the blog on Foundations and Floors.

Figure 2: Building Construction

Photo courtesy of Pexels

Part B Fire Safety

Figure 3: Fire Hose Reel and Extinguisher

Photo courtesy of Pexels

The fire safety requirements include having a means of escape, linings and walls in between buildings being resistant to ignition, minimising external fire spread, and access and facilities for the fire service. There are also specifications on fire extinguishing installations such as the requirement to have an automatic sprinkler systems if the floor is more than 30 metres above ground level.

Part C Site Preparation and Resistance to Moisture

The ground should be reasonably free of vegetable matter. There should be adequate drainage to prevent the passage of ground moisture to the interior. The floors, walls and roof should prevent the passage of moisture to inside the building.

There are standards for dangerous substances Figure 4: Construction Site

including adding a sealed membrane to the Photo courtesy of Pexels

footprint of a building in high radon areas. Radon

is a radioactive element which can occur naturally in the soil, and exposure to high concentrations of radon is known to increase the risk of lung cancer (Radon, 2021).

Part D Materials and Workmanship

Part D outlines standards which require that the materials used should be fit for the job, and resistant to moisture and attacks by material in the subsoil. There should be a high level of workmanship. For more information on materials, see blog on Building Materials.

Letter plates should be a certain height so that postmen and other users of the letter Figure 5: Mixing Cement plates do not have to bend to the ground Photo courtesy of Pexels when delivering letters.

Part E Sound

Walls and floors should be constructed to provide reasonable sound insulation. The common internal part of building shall limit reverberation.

There should also be a testing programme in place to test the sound insulation.

Figure 6: Megaphone

Photo courtesy of Pexels

Part F Ventilation

Ventilation should be provided to limit moisture and harmful pollutants and prevent condensation in roofs.

There are standards for natural ventilation, such as the size of windows, and for mechanical ventilation.

Figure 7: Vent

Photo courtesy of Pexels

Part G Hygiene

Dwellings should have a bathroom with a shower or bath and washbasin, and a kitchen with a sink.

Sanitary conveniences shall be adequately separated from cooking facilities and they shall have washbasins.

Figure 8: Bathroom

Photo courtesy of Pexels

Part H Drainage and Waste Water Disposal

Drainage systems shall be adequate for the hygienic disposal of foul waste water and for adequate disposal of surface water, with standards for man holes gutters, storage tanks etc. Foul waste and surface water disposal systems should be separate.

Wastewater treatment systems should function to a sufficient standard not to cause harm to health.

For more information on drainage and wastewater, see blog Drainage and Wastewater Treatment.

Figure 9: Surface Water Drainage Pipe

Photo courtesy of Pexels

Part J Heat Producing Appliances

A heat-producing appliance should have adequate air supply. Solid fuel, oil and gas burning appliances require standards such as ventilation in the room.

Oil storage tanks should be constructed to reduce risk of fuel escaping.

Figure 10: Gas Cooker

Photo courtesy of Pexels

Part K Stairways, Ladders, Ramps and Guards

Stairways, ladders and ramps shall be constructed to afford safe passage with standards for the rise, pitch and handrails.

The sides of every floor balcony and roof shall have guarding. Vehicle ramps, floors and roofs should have barriers.

Figure 11: Stairway with Guarding

Photo courtesy of Pexels

Part L Conservation of Fuel and Energy (Dwellings/ Non-Dwellings)

Buildings should be constructed in a way that limits energy consumption and carbon emissions. This includes standards for insulation, air filtration, air conditioning, and limitation of primary energy use and C02 emissions for new buildings.

When a building undergoes major renovation, such as a large extension, the minimum energy performance requirement if the renovated part of the building must upgraded in order to meet the optimal level of energy performance in so far as this is technically, functionally and economically feasible.

Figure 12: BER Rating Chart

Photo from Homerating.ie

Part M Access and Use

Adequate provisions should be made for people to access the building and its sanitary facilities. This includes standards for ramps, circulation within buildings, having sanitary facilities on the ground floor and a certain height for switches and sockets.

Figure 13: Ramp

Photo courtesy of Pexels

REFERENCES

Radon (2021) Geological Survey Ireland.[online] Available from <https://www.gsi.ie/en-ie/programmes-and-projects/tellus/research/Pages/Radon.aspx> [accessed 1 May 2021]