Renovations and alteration work

In this section, you will find instructions for conducting, building or dwelling renovation and alteration work on wet rooms, fireplaces, balconies, terraces, windows, doors, facades and technical equipment, and for common housing cooperative construction projects such as the installation of lifts, pipe renovations and attic construction.

On this page

Building permits are always required for building or dwelling renovation or alteration work that is comparable to building something new or may have an impact on the safety or health conditions of the building's occupants.

Examples of changes that require a building permit:

  • changes in the intended use
  • changes to load-bearing structures 
  • large-scale changes in the building services engineering 
  • changes that affect the fire protection solution
  • structural changes, such as the construction of a canopy or balcony

1. Instructions for renovations and alteration work

Review these instructions to see whether your planned construction project requires a permit. Some minor projects do not require a permit, but they need to observe the city’s guidelines and other possible regulations. It is best to hire a professional to manage your project and be involved in the design, negotiation and permit application process. 

Renovations and alterations in a building or dwelling

You need a building permit if you intend to build new extensions for a building or to increase the floor area within an existing building. In order to build an extension, the plot must still have some unused building space available from the maximum built floor area allowed on the plot. 

A building permit is required for changing the intended use of a building or a part of the building. Changes in the intended use include, for example, restoring or changing an office or business space into a dwelling or using an office space for residential purposes.

Find out if the local detailed plan allows this kind of change, if the building is protected, if the space is suitable for residential use, and determine the space’s relevant technical requirements. Evaluations of the functionality of the ventilation, fire compartmentation, sound insulation and emergency escape routes must also be attached to the permit application.

An action permit is required for renovations that seek to combine two dwellings into one or divide one dwelling into multiple residential spaces. If the project includes any demolition or changes to load-bearing structures, you will need to apply for a building permit. 

You need to attach a project report, a site plan and a floor plan to the permit application. The floor plan must show the location of any structures to be demolished and the location of new structures, as well as emergency escape routes, fire compartmentation, sound insulation and the functionality of ventilation.

When a dwelling is divided, both new residential spaces must have functional emergency escape routes. For example, a rescue department vehicle must have close access to windows that act as evacuation passageways. Likewise, the staircases and entrances must be wide enough for emergency response workers to be able to enter the dwelling and navigate the stairs with a stretcher. The standard minimum stretcher size is 2400 mm x 600 mm. Keep in mind that the minimum floor area for a habitable room is 7 m² and the minimum floor area for a dwelling is 20 m².

A building permit is required for any alteration work that has an impact on the safety or health conditions of the building's occupants. 

Examples of changes that require a building permit are:

  • changes in the intended use
  • changes to load-bearing structures 
  • large-scale changes in the building services engineering 
  • changes that affect the fire protection solution
  • structural changes, such as construction of a canopy or balcony

A bathroom or sauna can usually be built, renovated or extended within an existing building without a permit if the change only applies to the dwelling’s interior. Remember to seek the housing cooperative’s permission for alterations to wet rooms. It is also good to hire a professional to manage your project

You will need a building permit or statement for wet room renovations and alterations inside a dwelling if:

  • the project alters interior or facades that are protected
  • the load-bearing structures in the floor or walls are altered, or the load on the structures increases substantially
  • the structures within the area to be altered have incurred water damage. Use the Lupapiste online permit service (currently available in Finnish and Swedish only) to see whether you need a permit.

A Lupapiste permit processing professional will be able to give you more information about the required attachments to your permit application for wet room projects. The following appendices are usually required:

  • master drawings
  • building plans that indicate how the alterations will affect the load-bearing capacity of the floor or intermediate floor
  • ventilation, water and sewer system plans
  • threshold details, and in cases where the floor structure is raised, proof of the housing cooperative’s approval 
  • assessment of the alteration work’s impact on the sound-insulation of the structures
  • assessment of the noise level caused by HPAC equipment
  • facade drawings if the project will impact the facades of the building

If an old fireplace is replaced with a new one, it is not necessary to apply for a permit from Building Control. Before you replace the fireplace, you must investigate whether the floor or intermediate floor can bear the weight of the new fireplace, and whether the new fireplace is compatible with the flue. If the flue has not been used for a long time, the condition of the flue must be assessed by a chimneysweep, who will prepare a statement.

If you are building a completely new fireplace and provisions for the fireplace were made already during the building phase, you may need to submit a Z statement. If no provisions were made for the fireplace during construction, you will need to apply for a building permit. 

Hire a professional to prepare a report that indicates the load-bearing capacity of the floor or intermediate floor, a chimneysweep’s statement on the condition of the flue, the compatibility of the flue and chimney with the fireplace, and the arrangements for the fireplace hearth.

Balconies, terraces, windows and doors

A building permit is not required for construction and/or glazing of a terrace or balcony in a detached house, if the structure complies with the relevant Building Control guidelines.

A permit is not required for a terrace that is lower than a step high. Keep in mind that no more than one third of a plot’s surface area should be used for the dwelling, and this includes canopies and terraces. Remember to check the local detailed plan that governs the area.

If you are uncertain whether your project meets the requirements referred to in the guidelines, submit a consultation request by clicking on “Kysy neuvoa (Ask for advice)” in the Lupapiste online permit service (currently available in Finnish and Swedish only).

Use the Lupapiste online permit service to contact permit processing professionals. They can confirm if your window or door alteration plan is in accordance with the regulations. Your plan needs to include photographs of the building and its different window and door types and a brochure or something similar from the window or door manufacturer. 

An action permit is always required for the following projects:

  • changing the frame or frame division of a window or window door
  • changing the original building material, finish or colouring of a window or door 

A Lupapiste permit processing professional will be able to give you more information about the required attachments to your permit application. 
If changing the building’s facade is prohibited by the local detailed plan governing your area, the doors and windows of the building cannot be altered in a way that differs from the original. If you are planning a renovation or alteration of the doors and windows of a protected building, contact Building Control by clicking the Lupapiste online permit services’s “Kysy neuvoa (Ask for advice)”.

Facades and technical equipment


You do not need a permit for changing the material of your roof or the colour of the façade or roof on your house or outbuildings, if you live in a detached house and the local detailed plan governing your area contains no related restrictions. Changing the facade material of a detached house requires a permit. In principle, changing the colour of a facade or roof in a detached house that is protected requires a permit, even if the aim is to replicate the original colours. 

Permits are also required to change the colour and material of a block of flat’s roof and facade.

Renovating the exterior of a building always requires a building permit or action permit. Actions subject to permit are, for example, altering the shape of a roof, making new door or window openings, and adding supplementary insulation to the façade or adding a ventilation gap.
For projects that are subject to permits, it is best to hire a qualified building designer (a licensed architect) who can collect the necessary attachments for the permit application. Depending on the project, this would include a colour study, cityscape assessment, detailed plan and facade drawing, and a colour plan. In the case of protected structures, city museum instructions may also be required.

Procedural guide for facade colouring and colour changes e (PDF, 2 Mt) (In Finnish)

Guides on detached houses built during the post-war reconstruction period (rintamamiestalo):
On repairing windows (PDF, 2 Mt) (In Finnish)
On painting and façade colours (PDF, 2 Mt) (In Finnish)
On repairing the facade (PDF, 2 Mt) (In Finnish)

Facade paintings or murals are paintings, images or texts on walls or elsewhere in the built environment. Work such as this that is displayed for more than two weeks is usually subject to a permit. An action permit is required if the painting impacts the cityscape or landscape. If the work is located in a residential area, the neighbours must be consulted.

No permits are required for mural walls maintained by the City of Helsinki’s Youth Services or leisure activity locations associated with youth centres. Short-term (displayed for less than two weeks) and small murals are also not subject to permits. Even if an action permit is not needed, it is a good idea to contact Building Control in good time via the online permit service Lupapiste’s “Kysy neuvoa (Ask for advice)” to ensure that the painting or mural is permissible.

You will need the following attachments for the permit application:

  • a description of the technical aspects of the implementation
  • information on the person(s) planning and executing the project
  • the detailed plan governing the area, the facade drawings of the surface that will hold the mural
  • a photograph of the location and a conceptual image of the mural in its environment
  • It is also good to attach other material that can affect the permit decision. These can be things such as photographs of the mural’s broader environment or a description of the ways in which the mural will take the existing cityscape into account.

For more detailed information about designing and implementing a mural: Murals (PDF, 1 Mt) (In Finnish).

Installation of an advertisement device is usually subject to a permit. All outdoor advertising equipment, such as billboards along roadways, ads posted on lampposts and electronic screens require a permit. 

In principle, advertising devices cannot be placed:

  • at an intersection, if the ad content changes or contains moving images
  • in a manner that disturbs the public city space or makes the area inaccessible in some way
  • on the facades or plots of protected buildings or buildings that have cultural-historical value 
  • on the corners, bay windows, pillars or other protruding parts of buildings
  • directed towards apartment or workplace windows if the device is electronic
  • in a manner that disturbs or harms the environment
  • on a residential building’s facade without justified cause and a valid action permit

Placing and attaching advertising devices

  • A sales, information or advertising device attached to a building may, at maximum, reach 0.8 metres into the street area or other public area. 
  • Window and door awnings and terrace canopies may, at maximum, reach 1.5 metres into the street area or other public area. There must be at least 2.5 metres of vertical clearance. 
  • The shape, colouring and structure of the device must be suited to the building and surrounding environment. 
  • The advertising equipment must be attached firmly and kept in good condition. Broken equipment must be either replaced or removed immediately. 

Advertising equipment may not be used as a lighting fixture; its brightness must be adjusted to fit the lighting in the area. The brightness of commercial public displays must be lowered during the night. Check permissible thresholds from the instructions below.

For more detailed instructions on advertising equipment: 
Advertising equipment on buildings and plots (PDF, 1 Mt) (in Finnish)
Placement principles for outdoor advertising (pdf, 3 Mt) (in Finnish)


If you install an air source heat pump according to our instructions, you do not need a permit.

A permit is not required for an external unit of an air source heat pump or cooling device that is attached to the exterior on the wall of a detached house in such a way that it is not visible from the street.

Instructions on the installation of an air source heat pump: Technical devices and systems on building facades and roofs (PDF, 1 Mt) 


If you install a solar panel according to our instructions, you do not usually need a permit. However, action permits are required to install solar panel on the roof of buildings that are either protected or have cultural-historical value. You also need an action permit if you are planning to install a solar panel on an exterior wall or balcony railing, for example.

Instructions for solar panels: Technical devices and systems on building facades and roofs (PDF, 1 Mt) 

Housing cooperative construction projects: installation of lifts, pipe renovation and attic construction

The construction of a retrofit lift always requires a building permit.

Designing a retrofit lift for an older block of flats requires an experienced designer who is specialised in the design of retrofit lifts. This person can survey the different lift construction options and choose the best solution for the housing cooperative and its stakeholders.

The construction of a retrofit lift also requires an experienced building and lift contractor specialising in the construction of retrofit lifts.

The City of Helsinki’s “Lift Project”(Hissiprojekti) provides housing cooperatives in the city with free advice on the procurement of retrofit lifts.

Further information is available on the Hissiprojekti webpages (in Finnish) (Link leads to external service)

Pipe renovation refers to the replacement of a property’s water supply and sewage lines (KVV), renovation of the wet rooms, and the related building technology work.

A building permit is required for repair or replacement of a building’s water supply and sewage system. A project manager should be appointed for the project, along with a HPAC design engineer, an architect and a structural engineer. 

If the building to be repaired is occupied, the safety of the residents must be ensured during the renovation. A separate plan should be drawn up to protect the rooms from dust and temporarily store certain items. 

The Lupapiste online permit service will provide you with the necessary information about the required attachments when you apply for the pipe renovation building permit. The project manager is responsible for collecting the required attachments, which normally include the following: 

  • a project statement that indicates the project content 
  • an extract from the trade register that indicates the housing cooperative members with the authority to sign documents
  • an energy report on the renovation
  • master drawings
  • water supply and sewage system (KKV) plans
  • the ventilation plan
  • a connection point statement
  • reports on the stormwater treatment 
  • building and fire compartmentation plans

A Lupapise permit processing professional will be able to answer any questions you have about pipe renovations. For more instructions on pipe renovations: Building permit procedure for pipe renovations (PDF 1 Mt) (in Finnish)

A deviation decision is in effect for the entire City of Helsinki which allows the attics of residential flats to be altered for residential use, in opposition to local detailed plan regulations and possible building bans governing  the area. The deviation also applies to buildings in the central business district that were originally built as residential blocks of flats and now house both residential and business premises.

Conditions of attic construction:

  • The property must have suitable prerequisites for attic construction and the finished rooms must meet the basic requirements for living space.
  • Improvements to the housing cooperative’s common spaces and comfort level are made in connection with the construction.
  • The building’s characteristic features must be the starting point for the attic construction. The building’s external and internal architectural values cannot be corrupted. The new building parts must suit both the building’s characteristic features and the cityscape.

The construction must primarily take place on the inside the existing roof.

First establish whether the attic space is suitable for flat construction with an architect who is already familiar with attic construction. The most important matters to be clarified include:

  • sufficient height and verified dimensions of the space
  • existing structures and chimneys
  • light intake and the possibility to create new windows
  • access to the attic and the possibility of building a lift to the staircases
  • measures to improve the comfort level of the housing cooperative 

Once the housing cooperative has decided to build flats in the attic, specialist designers should be hired for the project. The designers must have experience with demanding reconstruction projects and housing design. The housing cooperative is responsible for the quality of the construction, the hiring of qualified people, the implementation of the project and the monitoring of the implementation. An architect will prepare the preliminary drawings and make an appointment with a permit processing professional at Building Control for the preliminary negotiation.

Attic construction always requires a building permit.  The Lupapiste online permit service’s Instructions for attic flats (Ullakkoasunnot) and permit processing professionals can provide you more information about the required attachments for the building permit.

For more instructions on attic construction:
Area deviations on attic construction in residential blocks of flats, Urban Environment Committee (PDF, 1 Mt) (in Finnish)
Instructions on the building permit process (PDF, 1 Mt) (in Finnish)
Instructions on attic flats (PDF, 5 Mt) (in Finnish)
Cityscape zone map of attic construction (PDF, 1 Mt) (in Finnish)

2. Determine whether your construction project is feasible

Start your construction project by checking the detailed plan governing the area in which your plot is located. The detailed plan determines what can be built on the plot. View the relevant detailed plan on the Map Service. The link opens a new window. 

Helsinki map service(Link leads to external service) 

Some areas of Helsinki are also subject to regional planning guidelines.

Regional planning guidelines.

The City of Helsinki’s building code is a guideline that regulates construction and stipulates, among other things, what can be built and repaired without a permit from Building Control.

City of Helsinki building code


3. Ask for advice on Lupapiste

If you cannot find your construction project or you need advice, contact Building Control through the Lupapiste online permit service (available in Finnish and Swedish only).

On Lupapiste, you can receive general advice, make appointments, prepare a permit application and submit documents. Start your project by submitting a request for advice by clicking on “Kysy neuvoa (Ask for advice)”. After you receive a reply, you can, make the request for advice into a permit application if you wish and continue preparing the application.

Follow these steps: 

  1. Log in to Lupapiste and register in the service.
  2. Select “Kysy neuvoa” (“Ask for advice”) from the top-right corner.
  3. Enter the address or property identifier of the project.
  4. Follow the instructions. Select the type of project you wish to begin.
  5. Click “Kysy neuvoa” again when you are finished
  6. Write a short description of the project and your questions.

4. Check whether you need to attach an energy statement to your permit application

Many renovation and alteration projects that are subject to permits must include an energy statement as an attachment to the permit application.

The following projects do not require an energy statement:

  • buildings with floor area of less than 50 m²
  • projects in which the section to be renovated or altered is at maximum 50 m² or less than 10% of the floor area of the entire building
  • combining and dividing dwellings
  • interior changes to dwellings, such as repairing or constructing a wet room or altering the load-bearing structures
  • window changes in which the U value is 1.0 W/m²K or better
  • window repairs of a building with a protected facade
  • balcony changes
  • advertisements

Instructions: Energy efficiency in renovation projects (PDF, 1 Mt) (in Finnish) 

Form to be used for the energy statement: Statement on the energy efficiency of renovation and alteration work, (PDF, 1 Mt) (in Finnish)(Link leads to external service)

Energy experts support housing cooperatives(Link leads to external service)