Primary school med library, Vega school, Vännäs (Västerbotten SE)
Implementation concept submitted by:
Nenet in cooperation with Thomas Greindl, architect, Certified European Passive House designer, CEPH, Sweco Architects AB, Umeå
Region / local area where the pilot is situated:
County of Västerbotten, Vännäs municipality, Sweden
Type of Building
Ecologic and sustainable Passive House school building for
• daycare center
• elementary school
• secondary school
• integration school
• town library
Altogether for around 600 school children, 35 teacher and other staff members.
Region / local area where the pilot is situated:
Kommendörsgaten 9, 91181 Vännäs, Västerbotten, Sweden
https://goo.gl/maps/DkGPg
Total effective area:
BBR (Swedish system to count the area) 5189 m2
PHI (for the Passive House certificate) 4260 m2
Area outside the Passive House boundary´s 310 m2. Number of levels above earth: 2 levels for school and teacher. One room for the ventilation units is in level 3.
Source of energy for heating: District heating with renewable fuel, with only use of returning district heat water.
Type of heating system:
Ceiling –mounted heating and cooling system. Radiant heating system is a comprehensive technology for realizing optimum comfort in the rooms with a simultaneous aesthetic integration in architectural room concepts. Radiant ceiling panels give off most of their heat through radiation. The remaining heat is transmitted via convection. The radiation of heat is achieved by passing heated water through pipes. The benefit of the system lies in the direct heating effect it has on the body, without the need to heat another medium for example air.
Type of water heating system:
Energy from the district heating system (returning water).
Type of ventilation system:
Passive House certified central ventilation systems with heat recovery system and an effective heat recovery rate of 86%.
Owner and costs
Name of owner: Vännäs municipality
Date of construction/renovation: 3/2014 – 7/2015.
Total cost: 10 000 000 € (90.000.000 SEK) project costs, building included all fixed equipment, school yard an external facilities.
Financing resources: public.
Short description of the pilot project
The Nya Vegaskolan in Vännäs will be built as passive house according to the international passive house criteria (PHI). It will also be certified according to the sustainable certification system “Miljöbyggnad Guld”. This is so far unique for Sweden. The building envelope and insulation is 100% renewable materials, while the inner supporting system is armored concrete due to costs. The building has 4260 m2 on two levels and will be used by 600 pupils and 35 teachers.
The heat demand is 87% below building regulations and the total energy demand is 80% below the building code. Certification criteria for total specific primary energy demand is ≤ 120 kWh/(m²a), for heating ≤ 15 kWh/ms,a), Airtightness Pressure test result, n50≤ 0.6 h‾¹.
All energy calculations have been done with the Passive House Planning Package (PHPP). Use of low-emission products is an important part of the project.
Time schedule:
The decision to build the new Vegaskolan as a model project for sustainable building was taken in 2012. The planning process started 2013, the same year the municipality agreed to follow the MountEE pilot project criteria. The construction will start fall 2014 and the building is expected to be completed late summer 2015.
The main objectives of the project “Ecological and sustainable passive house school” are:
• Implementation of all policy decisions of the City Council taken in the context of sustainable living and building.
• To Fulfill and implement the European targets of near-to-zero energy building for the years after 2018 for public buildings and 2020 for all buildings, already today.
• To showcase the possibility of a zero energy, zero waste and zero Pollution building
• To create a NZEB as far north as possible in Europe.
• The design of a resource-effective building in all areas.
• The reduction of CO₂ emissions plus achieving a negative CO₂ balance in the life cycle of 50 years.
Quality of location and facilities
Vega school with the library will be located on municipal land in the middle of a major inner-city residential area mixed with a hotel and some shops for daily needs. The distance to the center is 200 meters.
The new school replaces a damp damaged building which also contained asbestos-containing components and which has been located at the same place. There will be no new sealed surfaces. Through the new planning of the exterior surfaces ecological diversity and value of green plants is increasing.
Distances to services and transport:
• Covered bicycle parking spaces are located at the main entrance.
• 200 meters from the nearest bus stop
• 700 meters to the upper school class 7-9 and high school class 10-12
• 50 meters to the nearest supermarket
• 250 meters from the town hall
• 200 meters to the town center
• 100 meters from the central bus station
• 100 meters to the train station with trains to North and Southern Sweden and commuting to Umeå
• 30 km to Umeå airport
Process and planning quality
The project’s environmental and quality plan includes the following topics:
• Non-toxic indoor climate with low thresholds for formaldehyde, VOCs, TVOCs, CO2, and radon – we need to build for people = strict limits on emissions in indoor air
• Highest possible resource and energy efficiency with maximum comfort and quality while also reducing CO2 emissions = international Passive House certification
• Renewable energy for residual energy demand = Nearly Zero-Energy Building
• Renewable, zero-emission construction materials with low embodied energy levels (LCA)
• External quality assurance (not typical in the Swedish construction process) on the construction site plus quality assurance based on Passive House and sustainability certification
• Materials and structures with long service lives, low maintenance expenses, easy to update and dismantle (LCC)
• Flexible floor plans, flexible and easily accessible building services equipment, non-loadbearing walls inside, accessible ventilation system
• Possibility of prefabricating building components for higher construction quality
• Good location, well connected to local transportation and commercial and public facilities
• Use of existing infrastructure
According to plans, continuously information exchange between MountEE and architect was provided.
Information for users:
Under the hole planning process there were meetings every 2 weeks with the project-, building- and school management. All of them have been involved in the process regarding the overall concept, the floor plans, the function of the building and the selection of materials and equipment.
A large display in the entrance area will show the current and the average annual energy consumption.
Implementation of Service Package
Nenet is cooperating with the responsible architect Thomas Greindl and offering service and support following the structure of the service package.
This means in practice that the standard is the same as in the service package regarding moduls 2-5. Certification as Miljöbyggnad Guld and passive house following PHI criteria secures a high level of quality.
Energy and Utilities
The primary energy demand includes the energy demand for heating, cooling, hot water, ventilation, auxiliary electricity, lighting and all other uses of electricity. The limits set above for the specific useful cooling demand and the primary energy demand apply for schools and buildings with similar utilization patterns. These values are to be used as a basis but may need to be adjusted according to building use. In individual cases where very high internal heat loads occur, these values may also be exceeded after consultation with the Passive House Institute. Proof of efficient electrical energy use is necessary in such cases.
All energy calculations have been done with the Passive House Planning Package (PHPP) which is the key design tool used when planning a Passive House and as such, serves as the basis of verification for the Passive House Standard.
a) Specific heating demand:
Accordingly to the Passive House Certification Criteria for
• specific space heating demand ≤ 15 kWh/(m2,a)
• total specific primary energy demand ≤ 120 kWh/(m²a)
• airtightness Pressure test result, n50≤ 0.6 h‾¹ (here n50≤ 0.3 h‾¹ or 0,15 l/(sec, m²)
b) Specific cooling demand
There is no cooling demand because of the temporary exterior sun protection with external venetian blinds.
They can be adjusted to almost any angle – comfortably from inside the room. Thus, the slats allow daylight to enter into the interior while still protecting visual privacy.
As a heat shield in the summer and additional insulation in the winter, the external venetian blinds improve the energy balance of building.
The adapted automated slat control ensures that external venetian blinds meet the requirements for energy efficiency class A. Optimum daylight utilization while minimizing heat input with the external venetian blinds the project benefit from significant cost and energy savings for artificial lighting and air conditioning.
Additionally there is a bus-system that coordinate the sun shading systems, ventilation, heating, with each other to be able to react effectively to external weather influences.
In addition there is an ice and a direction dependent wind monitoring.
c) Specific lighting demand
In the whole project we use demand controlled LED lights which daylight- and occupancy sensors which are cooperating with the exterior venetian blinds with concave light control slats.
d) Primary energy demand
Total specific primary energy demand *) ≤ 120 kWh/(m²a)
Reduced primary energy demand through following measures:
1. Reduce the heating demand to around 15 kWh/(m2a) = intern. Passive house standard.
2. Demand controlled ventilation units with sensors for humidity, VOC, CO₂ and temperature
(An important requirement for demand controlled ventilation is a nontoxic indoor air environment/quality. If this criterion is not met it requires a much higher ventilation rate to keep the air free of unhealthy emission )
3. Avoidance of cooling demand through temporary sunshade systems, naturally night ventilation concept.
4. Reduce the use of electricity for artificial light, pumps and fans.
5. Reduce the use of hot water and the losses of the hot water circuit through extra thick insulation.
6. Use of the returning water of the district heating grid.
7. Use of district heating grid with a CHP system (combined heat and power coupling) and a PEF around 0,85.
8. Use of district heating grid which uses 90% biomass.
e) Renewable energy
District heating with renewable fuel, with only use of returning district heat water. For lighting: Certified Green Electricity. Not finally decided: a PV plant or a share in wind power plant.
All energy calculations have been done with the Passive House Planning Package (PHPP).
There is a space allocation plan for the project which also is used as a tabulation for all building materials.
Part of PHPP is to take into account of all internal heat gains, passive solar gains, thermal bridges and more.
Part of the planning process was to develop an air tightness concept with detailed drawings and material recommendations.
There is also a training of construction workers as the airtight layer may be practiced. In any case there will be two Blower Door tests together with infrared thermography.
Health and Comfort
High level of comfort because of the use of an exterior temporary sunshade systems and naturally cooling. Part of the sustainability and quality program in the project are these sound pressure levels:
LA,eq < 30 dB (A) class rooms
LA,eq < 25 dB (A) Rest rooms
LA,eq = effective sound pressure
Building materials and constructions
Part of the tender documents are requirements for all building materials with limited values for poison / unhealthy emissions for
VOC; TVOC; Formaldehyde and Radon
Furthermore it is not allowed:
To use HFC´s in the production process of XPS insolation under the ground slap.
To use insolation panels with brominated flame retardants.
To use PVC pipes for wastewater and conduits.
To use refrigerants with ODP > 0 and GWP > 5 in cold storage systems.
All chiller, freezer, cooler in the professional kitchen use as an environmentally friendly refrigerant CO2.
All materials need an EPD, a sustainable certificate and a report for emissions.
Part of the tender documents are requirements for all building materials with limited values for poison / unhealthy emissions:
All chiller, freezer, cooler in the professional kitchen use as an environmentally friendly refrigerant CO2.
Avoidance of PVC:
It is not allowed to use PVC pipes for wastewater and conduits.
No floor coverings are used. Instead we use linoleum, wood parquet and tiles.
Certified Passive House windows, doors and curtain walls are made of wooden frames with aluminum cladding.
The exterior venetian blinds are made of aluminum.
Ventilation pipes are made of galvanized sheet metal.
Ecological optimization of building materials:
All materials need an EPD, a sustainable certificate and a report for emissions.
The variety and numbers of materials were reduced and later on renewable, emission free building provisions produced as closed as possible to the building side were chosen.
The results of a comparative LCA is the use of:
• Wooden beams
• Cellulose insulation (without Borax)
• OSB 3 panels without Formaldehyde
• Wood fiber insulation board
• Ceilings with glued laminated timber
• Glued laminated timber for bearing construction
• Linoleum floors
• Wooden parquet
• Wooden panels
• Wooden frames for doors and windows
• Paintings with very low emissions
Evaluation and follow up
According to the joint evaluation guidelines and using interviews with the involved parties in the project as well as the continuous discussion of the project by the RCC.
Contact project owner
Organisation:
Vännäs Kommun Fastighetsavdelning/property management
Project management and contact person:
Vännäs kommun
Lars-Åke Forsgren
Lars-Ake.Forsgren@vannas.se
Telefon: 0935-142 21, 070-378 87 47
http://www.vannas.se/default.aspx?di=8846
http://vegaskolan.wordpress.com/
Architect:
Sweco Architects Umeå
Responsible projektmanager Bo Jonsson,
bo.jonsson(at)sweco.se
0046(0)706745216
Sustainability, Passive House certification, Certified European Passive House designer, Thomas Greindl
Thomas.greindl(at)sweco.se
0046(0)76-8290156