Flagpole heights in Finland – usual lengths and building permits

The height of a flagpole affects how the flag is seen, how large a flag suits the pole and what foundation the pole needs. According to the Ministry of the Interior, the pole’s height is determined by the height of the house, and the Ministry has published an indicative table of ridge height and pole length. This guide describes the usual heights and the limit in the Building Act.

Pole height and the house

According to the Ministry of the Interior, on one- or two-storey buildings the flag should show above the ridge even in still weather. At blocks of flats, according to the Ministry, the pole should reach the level of the third floor. Suomalaisuuden Liitto describes the same rule of thumb and points out that the shape of the plot and differences in ground level affect the final choice.

The Ministry of the Interior’s table describes an indicative relationship in normal conditions:

For a house with a ridge height of 5–6 metres, for example, the table gives a 10 metre pole and flag number 10.

Usual heights by type of site

• Cottages and small gardens: shorter field poles and telescopic poles, whose flag is seen within the yard.
• Detached houses: according to the table, usually 8–12 metres depending on the ridge height.
• Blocks of flats and housing companies: a pole reaching the height of the third floor.
• Businesses and public buildings: often 10–18 metres and a row of several poles.

The types of pole are described in the guide to types of flagpoles.

Height and flag size

The pole’s height and the flag’s size go together. According to the Ministry of the Interior, the flag’s height is about one sixth of the pole’s length, and according to Suomalaisuuden Liitto the flag number matches the pole’s length in metres. The house pennant is about half as long as the pole, according to the Association. The flag size for a given pole can be worked out with the flag size calculator, and the size tables are in the guide to flag sizes.

Height and building permits

The Building Act entered into force on 1 January 2025 and replaced the building permit, the action permit and the action notification with a single building permit (rakentamislupa). Under section 42 of the Act, a building permit is required for a new mast at least 30 metres high. Ordinary flagpoles are well below that.

According to the Ministry of the Environment, plan provisions, building regulations and the municipality’s building ordinance apply even when no permit is required. Under section 42(2) of the Building Act, a permit may also be required if the building has more than a minor impact on the townscape, landscape or cultural heritage, for example. In protected surroundings and in areas with a local detailed plan, height can therefore be a matter on which the municipal building control authority can give information. More information is in the guide to flagpole installation.

Height and foundation

A taller pole is thicker and heavier, and the wind exerts a greater force on it. The foundation therefore grows with the pole’s height. The manufacturer usually states the foundation dimensions by pole length, flag size and wind conditions. Height also affects the price of a flagpole, as described in the guide to buying a flagpole.