Welding rods sing in the seams of the steel stairs

Sparks, flames and smoke. All of these have been a common sight along the steel spiral staircase of Oodi in recent weeks. Extensive welding work is in progress, as the stairs, which were delivered to the site as 10 separate blocks, will now be attached together with thick welded seams. The seams, visible as dark vertical lines on the white railing, will of course be covered with paint. At this time next year, the library customers will be using the stairs without a hitch, moving from the lobby up to the third floor.

The spiral staircase of Oodi is both impressive and structurally unique. The complex consists of two spirals, which resemble the structure of DNA. It seems like this structure is hanging in mid-air, as it does not seem to have any support at the bottom and there is no support pillar in the middle. This magic trick will be accomplished by supporting the stair complex through the structures of the floor slabs.

“During welding, we are still using temporary supports, but after they are removed the staircase will be supported by the floor slabs. In part, this solution increases the frame’s load, which will grow further when the stairs are used by the library customers. We have taken the pressure and movements of the building into account: some seams allowing movement have been left in the library structures,” says YIT’s site manager, Janne Kurikka.

Proof of excellent work planning is the fact that the entire stairwell has been protected with tarpaulins from the bottom to the top, forming a tent. This means that the assembly work and the particles generated by welding do not disturb those working close by and the odour also stays in the tent around the stairwell. The goal is to complete the welding work by the beginning of April.

Facade will be clad with spruce

In April, Oodi’s appearance will start to change visibly. There are two reasons for this: the entrance floor will receive its facade windows and the outer surfaces’ final cladding work will be started.

The main entrance area, with its curving shapes, is a challenging area for cladding. Whereas straighter walls are quick to clad using elements, curving surfaces as well as the edges of various holes and gaps have to be covered using individual pieces. On the eastern side of the building, wooden cladding will be accompanied with aluminium plates.

Spruce was selected as the material of the wood cladding, says Site Manager Janne Kurikka, who is in charge of the frame and the facade. In the photo, he is holding a model piece of the cladding.

“The cladding consists of laths, but viewed from afar the surface will seem like a smooth wooden surface. Before starting the installation, the material will go through fire testing. A batch of wood treated with fireproofing paint will be exposed to open flame, and during the test we will monitor how well the protective paint stops the wood from charring. The protection must meet certain determined values. In the future, the facade will be treated with the fireproofing paint about every fourth year.”

Janne is also personally familiar with wood construction. A while ago, he finished his own, a little under 250-square metre wooden house in Porvoo. Janne, a 33-year-old civil engineer, acted as both the project’s architect and principal designer and also worked as a constructor. His three children and five cats now have plenty of space for roaming and playing!

Cables will be covered with an installation floor

 At this stage, the second floor in particular reveals the library’s ‘nerves and veins’ i.e. all the building technology that will be hidden behind walls or covered with an installation floor.

The library will feature a restaurant and two cafés, but the users of the small group working rooms on the second floor will also have their own kitchen. Its electric lines and sprinkler system pipes will soon be covered with an installation floor. The lighting installations on the second floor are also progressing well. The work must be finished before installing the installation floor, as it is not able to bear the weight of the scissor lift.

The woodwork of the arching staircase, intended for reading and working, is almost finished. After mid-March, plywood covers were put in place, and in the next stage the staircase will be covered with grey textile carpet.

Third floor waiting for its suspended ceiling

The children’s area in the northern end of the third floor is being prepared for the installation of the white, curving suspended ceiling. The model piece installed in the middle of the third floor in the beginning of the year has been approved and the work will proceed based on the experiences of its installation.

Currently, the ceiling of the children’s area is covered with hanging steel poles of various lengths, which will later hold the suspended ceiling. Gradually, it will cover the ceiling’s ventilation pipes and maintenance bridge.

After the indoor works start, the third floor’s large windows will be protected from scratches and dirt. The windows will be covered with a film to protect them from dust and their bottom halves will be covered with EPS boards. This allows work to proceed with less risk of damage occurring.

Worksite humour in bloom in Oodi

At this stage, indoor works require the use devices intended for working with timber and plywood, which means that the song of a circular saw, for example, is a frequent thing. The amount of sawdust could be staggering, but it is controlled with special sawing premises situated on the different floors, which are tents with a door that can be closed during the work.

Work goes quicker with some humour and laughter. A subcontractor has named their sawing tent their VIP premises.

The worksite is full of rules, but sometimes a little humour can be added, even in serious matters.



Text and photos: Liisa Joensuu/Tmi Magic Words

The library’s spiral staircase fell from the sky

The sky was the limit, when the spiral staircase bringing together the three upper floors of Oodi was majestically lifted into place in February. The stairs were lowered calmly, one part at a time, through a hole made in the roof, and suspended from the cables of a telescopic boom. Putting the stairs in place is one of the milestones of the construction process.

The stairs arrived to the site as a special transportation consignment in ten separate blocks. The finished staircase comprises two spirals, A staircase and B staircase, which diverge from each other. The total weight of the steel staircase is 80 tonnes. The stairs were manufactured by Normek Oy, as were the steel arches supporting the entire library.

In the photo, the first section of the stairs on the entrance floor is already in place and a cable is being used to pull the next part to the correct angle for welding. During construction, a massive hole was left between the floors, but the roof had to be reopened for the event.

“We built a weather guard on the roof above the stairs and removed the roof element. When the last part of the staircase has been lowered in place, the element will be closed and re-seamed. On the different floors, the staircase area is protected with EPS insulation boards to preserve heat while the roof is open,” says Worksite Manager Mansoor Ardam.

For customers with mobility issues, there are alternatives to the stairs: escalator and lifts. The frame of the escalator was also installed in February. The technology, railings and steps are still to be installed and, later on, adjustments and test runs will be performed. Installation of the lifts is also underway.

The shape of the suspended ceiling reveals the new shape of the skylights

A scale model has been installed in the suspended ceiling of the third floor, where the actual books will reside. The scale model helps those involved in the project study how the suspended ceiling can achieve a beautiful, wavy shape and how the skylights can be used to build a set of simple, yet elegant, light shafts.

The skylights were originally octagonal in shape, but as the scale model has been built they have gradually become round light shafts. The ceiling will be white and seamless and appear as if it is being sucked into the skylights. Due to the wavy form of the ceiling, both the ceiling and the skylight are positioned lower in some parts of the third floor and higher in others.

The light shafts will be built into vertical frames, as shown in the photo above. First, acoustic mineral wool will be placed into the frame. It will be covered with sprayable MonoRoc insulating plaster. This is a thick plaster, which helps soundproof the premises, repels water and is also energy-efficient. The base plaster will be later covered by a smoother, sprayed coating. Thanks to this method, the suspended ceiling will look like a solid rock ceiling.

The construction of the children’s section and its balcony at the northern end of the third floor is progressing quickly. Less than a year from now, story times will be held under the balcony!

The window installations in the library and the windows’ seaming work proceed on the eastern side of the building as the weather permits. The freezing temperatures of February have not disrupted the lifting of the glass panels into place in the mechanical fasteners, but seaming work requires a more temperate climate.

On the balcony side, i.e. the western side, over half of the windows have already been fitted into their mechanical fasteners. In the photo, workers are preparing to move a glass panel from the pallet by attaching it to the suction cup lift.

Not all the colours of the rainbow

According to an old Finnish nursery rhyme, a painter paints the house red and blue. Specialist painter Pasi Kalliokoski from Lainisalo Rakennusmaalaus Oy has to settle for black and white.

“In addition to black and white, the library’s colour landscape will include veneer surfaces. The furniture will add the colour. The ceilings and the ceiling channels have been painted black and so have the elements between ceilings and walls The walls themselves will not be painted much, since they will be covered with acoustic and veneer panelling. A few of the walls will be white. Black and white are standard colours in public premises, whereas other colours, structure surfaces and wallpapers are often used in commercial premises,” Pasi said before hopping into the man-lift and beginning the filling work on the structure below the suspended ceiling.

Carpenter Marto Jaakson was busy with building the socle of the second-floor wall separating the office spaces. Glass windows will be fitted along the corridor. Marto has been working on the library site for a year, and his work on the socle is going quickly.

The other carpenters are busy in the sitting area on the second floor, building its wooden frame. Within a few months, this area will be made into an inviting lounge and reading area.

More experience on the worksite

The newest site manager of the library worksite has plenty of experience to share. Jorma Pelkonen, 60, came to Oodi from an office building site in Kalasatama.

“Oodi, with its special structural solutions, is a significantly more challenging site than an office building I’m in charge of tiling, for example, and even the large toilet facilities in the basement are exceptional. Impressive, three centimetre thick limestone plates will be used as a visual element, attached to the walls with steel pegs.”

Jorma has been involved in the construction of apartments, offices, a hotel and even a railway tunnel. This list of references will be complemented with the central library before Jorma’s retirement at 63.



Text and photos: Liisa Joensuu, Tmi Magic Words

Facade windows on the sunrise side

The facade windows of the upper floor of Oodi have been lifted into place in the eastern wall of the building, facing the sunrise in the morning. Even though bright mornings are still some way away, the floor-to-ceiling high windows are a delightful sight amidst the greyness of early winter.

In the photo, manlifts are used in the dismantling of EPS boards, which were used as wall structures that insulated the building and protected it against wind before the windows were installed into their mechanical fittings. The windows will not be visible for very long on the Töölönlahdenkatu side, since when seaming work starts, the eastern wall will be covered by scaffolding and weather guards.

At this stage, the weather guard is covering the northern end of the building. The windows will be sealed both from inside and outside, and the weather guard will ensure suitable temperatures above freezing point and dry conditions.

The curving forms of the Oodi facade are starting to emerge now that some of the facade elements have been lifted into their fittings on the building’s western side. Later on, the elements will be covered with wooden framing, to which the final surface material will be attached. The balcony is located on the outward leaning wall.

The weather guard continues up to the roof, as work on the eaves is also taking place behind it. Site manager Mansoor Ardam inspects the seaming work on the windows. A seam can only be approved if it is straight and shows no signs of additional notches. The elastic mass adheres best to a dry, clean surface.

At the end on January, the worksite prepared for the installation of the third-floor facade windows on the sunset side too, on the building’s western facade. At first, glass pillars that support the surface windows were installed. When the glass pillars are tightly attached to their steel fittings, the up to nine-metre tall and 1,500 kilo multi-floor windows can be lifted in place with the help of a suction cup lift.

Heaters will be hidden from view

In the midst of the freezing winter, the average person may wonder how the aquarium-like third floor can be kept warm, when all the walls are made of glass, from the floor to the ceiling. The professionals have come up with a perfect solution, which also happens to be an aesthetic one too. No water-filled radiators will be installed in front of the windows so that they do not break the visual cohesion of the glass walls.

“The space is heated by narrow convectors installed under the installation floor that blow warm air at the lower edge of the glass,” Mansoor Ardam explains, showing how the draught-prevention solution will be built in front of the windows. The technology will be installed on the concrete floor, which will be covered with an installation floor. A library user can step right up to the windows without having to dodge the radiators.

In the computer modelling, the convectors are shown as the low red blocks below the windows. A great deal of building technology will be hidden between the roof and the suspended ceiling on the third floor: the ventilation pipeline is show in green, the sprinkler system in turquoise and the electric cables in purple. Only the sprinkler nozzles will be visible after the third floor’s wavy suspended ceiling has been installed.

The suspended ceiling, which is shown in the image as the neon green structure, will be installed at a notably low level compared to the height of the ceiling, due to the large amount of building technology. A maintenance bridge will be fitted over it, for example, and its installation work is now starting.

Partition walls reveal the room structure

Whilst the third floor is an open space, the second floor is filled in with different rooms. Their walls will be built based on the room’s purpose of use, either from glass, bricks or gypsum board. Right now, the gypsum walls are being built at a quick pace.

About half of the second floor gypsum walls have been finished. The corridor in the photo leads to the game rooms. The second floor brings the traditional library institution into a new era. It will house two general recording and editing rooms, a photography and video studio, a room for playing instruments, a control room, a drum room, offices, meeting rooms, a media room and rooms for small groups. In addition to the building of partition walls, acoustic insulation wool is being installed and gypsum boards are being painted and plastered on the second floor.

Worksite mornings are kick-started with stick workouts

In relation to work life, how the older generation teaches the younger ones and passes on so-called silent knowledge is a common topic of discussion. However, the younger generations can also teach the older ones and introduce something completely new to their work life.

At the Oodi worksite, mornings are now started with stick workout at 7 o’clock! Stretching and squatting for a few minutes gets blood pumping and warms up the muscles. This habit increases occupational health and safety. The exercises make reactions and coordination abilities quicker and help maintain balance better. Over a dozen people may take part in the classes. Photo: Anniina Kallioniemi.

The exercises are guided by 23-year-old Essi Tuomenoja, recently graduated construction supervisor and YIT’s site manager.

“Even though the workers were at first hesitant about the exercises, in the end they even built the exercise sticks, i.e. broomsticks, their own transport crate with a sling attached,” she says.

Essi graduated as construction supervisor from Häme University of Applied Sciences, and before Oodi worksite, she worked at six different sites. She finds it fascinating that each project creates a monument, whether it is an industrial hall or a library.


Text and photos: Liisa Joensuu/Tmi Magic Words

Bring in the electricity!

If Oodi only contained books, electrical installations would be simple. But this public living room offers its guests many special premises, from a cinema to studios, which makes electrical design and installations more challenging.

“The varying shapes of the spaces also bring added challenge: each space requires a specific approach. The plan can make things look simple, but they can be a great deal more demanding in practice,” says Janne Valtonen (left), the foreman of the electricians, and Seppo Kautto (right), project manager from ARE.

Work is also made more challenging by the fact that most Oodi premises do not have the suspended ceiling structure that hides the technology. Installations are left uncovered, which is why they must be made as neatly as possible. Electrician Ari Davidila installed the black cable racks on the second floor ceiling in December.

The cinema and studios are especially challenging spaces for electricity works. Their soundproofing requires unusual solutions for the inlets of electric cables.

“The cables can’t be installed as a bundle, we have to take them through the structures one by one, like wide-spread fingers, and soundproof them individually with the paste. In addition to this, we need to follow the acoustician’s specific instructions,” says Seppo Kautto.

Due to the soundproofing, the cinema and studio premises (pictured) will be equipped with a floating floor. The red Sylomer sound absorption mat has been installed on the concrete podiums. Its purpose is to separate the overlaying surface floor from the frame structure, absorbing the studio noise and preventing noise from carrying to or from the premises.

The Living Lab with its presentation technology is also counted as a special premise.

“Special electrical inputs are needed both for projectors and the room’s glass walls that can be darkened or opened electrically with a light,” says Janne Valtonen, explaining that the building’s electrical works are in their early stages.

“Even though the basement is 60–70% complete, only about 10% of the work on the second floor is ready. We are just getting started.”

The library will take up dozens of kilometres of electric cables Some of them can be hidden under the installation floor. The installation floor stands on its own feet and it will be installed over the concrete floor so that the technology is hidden between these two layers. This makes it easy to access the cables even after the building is fully completed.

Scale model of the suspended ceiling on the third floor

Unlike on other floors, the top floor of Oodi will be equipped with a suspended ceiling. The structure will be so unique that a scale model will be made of it at first.

A computer image shows the unusual, wavy form of the ceiling and the locations of the ceiling windows. The making of the approximately 6-metre-long scale model will begin after Epiphany, and an approval from the architecture agency will be sought for it before starting the construction of the actual ceiling.

The third floor is becoming a glorious kingdom of books and light. The green bars depict the future bookshelves. Light will flow in through both the wall-high facade windows and the ceiling lights. It has been decided that the pasting work of the facade windows will be carried out under weather protection. The protective cover will be installed before Christmas and the work will be started from the northern end. The space for the large steel spiral staircase is featured on the left. The stairs will be delivered to the site at the beginning of the year.

Unisex toilet in the basement

When a building houses a cinema and a restaurant as well as meeting and working premises, it also has to have enough toilet facilities. These requirements have been taken into account in the plans.

Toilets are available on every floor, but the primary public toilet facilities are in the basement. The toilet facilities have not been divided based on gender, which means that they are unisex toilets. Visitors can access the basement both on lifts and by the concrete spiral staircase. The spiral of the staircase is almost a work of art on its own.

There are over 20 toilet cubicles in the basement, so the lines should not be too long. The sinks and seats will be installed after the floor is cast. It was completed in mid-December. The facilities have underfloor heating, which keeps the moisture levels in check.

Cleaning up the facade

The installation of the facade elements was started on the western side of the building in December.

Before starting the installation, a few element supports were modified by welding them. The steel constructions are equipped with mounts for the elements, so the elements are quick to install.

One element at a time is lifted on its supports with the help of a frame such as this. The elements will be later equipped with wooden framing to ensure that air circulates well behind the final wood cladding.

The facade will be covered similar to the pictured northern end. The 280-mm-thick ready-made elements will be covered by the wood cladding and they act as thermal insulation and vapour barrier.

New generation of worksite management

Work site managers are sought-after people on different worksites, and a new work site manager intern has also been found for Oodi: Jarno Silén, student of production management of building technology from Häme University of Applied Sciences.

“I have been interested in building and making things by hand ever since I was a child, following in the footsteps of my father and uncle. Oodi is an interesting site. I will learn a lot here,” Jarmo said on his first day of work.



Text and photos: Liisa Joensuu/Tmi Magic Words