PAPERS PRESENTED AT THE CONFERENCE PASSIVHUSNORDEN 2012

Transcription

1 PAPERS PRESENTED AT THE CONFERENCE PASSIVHUSNORDEN 2012

2 TABLE OF CONTENTS DAY 1 MAIN CONFERENCE HALL... 5 THE SKARPNES RESIDENTIAL DEVELOPMENT - A ZERO ENERGY PILOT PROJECT... 5 NET ZEB OFFICE IN SWEDEN - A CASE STUDY, TESTING THE SWEDISH NET ZEB DEFINITION... 6 DESIGN OF A ZERO ENERGY OFFICE BUILDING AT HAAKONSVERN, BERGEN... 7 PASSIVE- AND PLUS ENERGY ROW HOUSES IN NEAR-ARCTIC CONTINENTAL CLIMATE... 8 POWERHOUSE ONE: THE FIRST PLUS-ENERGY COMMERCIAL BUILDING IN NORWAY... 9 SMALL CONFERENCE HALL A RETROFITTING OF EXISTING BUILDING STOCK AN ARCHITECTURAL CHALLENGE ON ALL SCALES DESIGN OF A PASSIVE HOUSE OFFICE BUILDING IN TRONDHEIM PASSIVE HOUSE WITH TIMBER FRAME OF WOOD I-BEAMS MOISTURE MONITORING IN THE BUILDING PROCESS TIMBER FRAME CONSTRUCTIONS SUITABLE FOR PASSIVE HOUSES SMALL CONFERENCE HALL B IMPROVEMENT OF TRADITIONAL CLAMPED JOINTS IN VAPOUR- AND WIND BARRIER LAYER FOR PASSIVE HOUSE DESIGN PASSIVE DYNAMIC INSULATION SYSTEMS FOR COLD CLIMATES POSSIBILITIES FOR CHARACTERIZATION OF A PCM WINDOW SYSTEM USING LARGE SCALE MEASUREMENTS ENERGY DESIGN OF SANDWICH ELEMENT BLOCKS WITH AGGREGATED CLAY HEATING AND COOLING WITH CAPILLARY MICRO TUBES INTEGRATED IN A THIN-SHALE CONCRETE SANDWICH ELEMENT SMALL CONFERENCE HALL C GUIDELINES FOR DEVELOPING ONE-STOP-SHOP BUSINESS MODELS FOR ENERGY EFFICIENT RENOVATION OF SINGLE FAMILY HOUSES OPPORTUNITIES AND BARRIERS FOR BUSINESS MODELLING OF INTEGRATED ENERGY RENOVATION SERVICES PROMOTION OF ONE-STOP-SHOP BUSINESS FOR ENERGY EFFICIENCY RENOVATION OF DETACHED HOUSES IN NORDIC COUNTRIES AMBITIOUS UPGRADING OF POST-WAR MULTI-RESIDENTIAL BUILDINGS: PARTICIPATION AS A DRIVER FOR ENERGY EFFICIENCY AND UNIVERSAL DESIGN

3 DAY 2 - MORNING SESSION MAIN CONFERENCE HALL DEVELOPMENT OF ENERGY EFFICIENT WALL FOR RETROFITTING ENERGIKONSEPT FOR OPPGRADERING AV NORDRE GRAN BORETTSLAG I OSLO KAMPEN SCHOOL - RETROFITTING OF AN HISTORIC SCHOOL BUILDING WITH ENERGY EFFICIENT VENTILATION AND LIGHTING SYSTEM REDUCING ENERGY CONSUMPTION IN A HISTORICAL SCHOOL BUILDING EXAMPLES OF NEARLY NET ZERO ENERGY BUILDINGS THROUGH ONE-STEP AND STEPWISE RETROFITS. 27 SMALL CONFERENCE HALL A OPTIMAL SPACE HEATING SYSTEM FOR LOW-ENERGY SINGLE.FAMILY HOUSE SUPPLIED BY LOW- TEMPERATURE DISTRICT HEATING.28 PERFORMANCE EVALUATION OF A COMBINED SOLAR-THERMAL AND HEAT PUMP TECHNOLOGY IN A NET-ZEB UNDER STOCHASTIC USER-LOADS HEAT PUMP SYSTEMS FOR HEATING AND COOLING OF PASSIVE HOUSES UTFORDRINGER MED INNREGULERING AV VAV ANLEGG I PASSIVHUS THE POTENTIAL OF FAÇADE-INTEGRATED VENTILATION (FIV) SYSTEMS IN NORDIC CLIMATE SMALL CONFERENCE HALL B MARIENLYST SCHOOL COMPARISON OF SIMULATED AND MEASURED ENERGY USE IN A PASSIVE HOUSE SCHOOL VERIFICATION OF ENERGY CONSUMPTION IN 8 DANISH PASSIVE HOUSES A PASSIVE HOUSE BASED ON CONVENTIONAL SOLUTIONS ON THE MARKET MEASUREMENTS OF INDOOR THERMAL CONDITIONS IN A PASSIVE HOUSE DURING WINTER CONDITIONS SMALL CONFERENCE HALL C FROM PASSIVE HOUSE TO ZERO EMISSION BUILDING FROM AN EMISSION ACCOUNTING PERSPECTIVE LIFECYCLE PRIMARY ENERGY USE AND CARBON FOOTPRINT FOR CONVENTIONAL AND PASSIVE HOUSE VERSIONS OF AN EIGHT-STORY WOOD-FRAMED APARTMENT BUILDING COST EFFECTIVENESS OF NEARLY ZERO AND NET ZERO ENERGY BUILDINGS ARCHITECTURAL FREEDOM AND INDUSTRIALIZED ARCHITECTURE - RETROFIT DESIGN TO PASSIVE HOUSE LEVEL ARCHITECTURAL QUALITIES IN PASSIVE HOUSES SUSTAINABLE VENTILATION

4 DAY 2 - AFTER LUNCH SESSION MAIN CONFERENCE HALL ERFARINGER MED PASSIVHUS ET SYSTEMATISK OVERBLIKK LIVING IN SOME OF THE FIRST DANISH PASSIVE HOUSES EVALUATION OF THE INDOOR ENVIRONMENT IN 8 DANISH PASSIVE HOUSES LESSONS FROM POST OCCUPANCY EVALUATION AND MONITORING OF THE 1 ST CERTIFIED PASSIVE HOUSE IN SCOTLAND OVERHEATING IN PASSIVE HOUSES COMPARED TO HOUSES OF FORMER ENERGY STANDARDS SMALL CONFERENCE HALL A BOLIGPRODUSENTENES BIM-MANUAL FOR PASSIVHUSPROSJEKTERING SIMULATION OF A LOW ENERGY BUILDING IN SWEDEN WITH A HIGH SOLAR ENERGY FRACTION SS : A SWEDISH STANDARD FOR ENERGY CLASSIFICATION OF BUILDINGS NS3701: A NORWEGIAN STANDARD FOR NON-RESIDENTIAL PASSIVE HOUSES SMALL CONFERENCE HALL B GEOMETRISKE KULDEBROERS INNVIRKNING PÅ NORMALISERT KULDEBROVERDI HAM AND MOULD GROWTH ANALYSIS OF A WOODEN WALL HYGROTHERMAL CONDITIONS IN EXTERIOR WALLS FOR PASSIVE HOUSES IN COLD CLIMATE CONSIDERING FUTURE CLIMATE SCENARIO PERFORMANCE OF 8 COLD-CLIMATE ENVELOPES FOR PASSIVE HOUSES LABORATORY INVESTIGATION OF TIMBER FRAME WALLS WITH VARIOUS WEATHER BARRIERS SMALL CONFERENCE HALL C. 58 VAD BEHÖVS FÖR ETT MARKNADSGENOMBROTT AV NYBYGGNATION OCH RENOVERING TILL PASSIVHUS - ANALYS FRÅN SEMINARIESERIE KOMMUNERS MÖJLIGHETER ATT STYRA UTVECKLINGEN MOT PASSIVHUS I SVERIGE OCH UTBILDNING AV BESTÄLLARE INOM KOMMUNAL SEKTOR PASSIVHUSCENTRA I NORDEN BUILD UP SKILLS NORWAY: COMPETENCE LEVEL ON ENERGY EFFICIENCY AMONG BUILDING WORKERS

5 Paper Passivhus Norden 2012 Overheating in passive houses compared to houses of former energy standards Arvid Dalehaug, Siri Birkeland Solheim and Stig Geving, Department of Civil and Transport engineering, NTNU, NO-491 Trondheim Norway Abstract Introduction When people are introduced to the passive house concept, with all the necessary means to reduce energy consumption, some people point out their concern about the building becoming too airtight, too warm, at least in summertime, too difficult to run etc. People's experiences from their present homes and other building are the reason for this reaction. Most people do experience uncomfortably high indoor temperatures many times every year due to many reasons, but not because of the houses are of passive house standard. Most people have never been in a passive house or a low energy house. To make the passive house standard acceptable in the market, it is necessary to check out the anticipated problems with the concept. In this paper we will look into the possible problem with overheating by running computer simulations on buildings of passive house standard and of houses with lower insulation and airtightness standard. Purpose and method To find out about possible overheating problems in passive houses compared to less insulated houses, the indoor temperature has been calculated with varying parameters. For the below described houses, insulation standard, airtightness, efficiency of heat exchangers, SFP-factor, window s solar factor, orientation of buildings and solar shading have been varied. In the calculations the warmest day is repeated for 5 subsequent days to avoid short term effects from thermal capacity. Description of simulated buildings Two types of buildings with two levels of energy standard are modelled for the simulation at three different locations in Norway. The constructions and layout of the modelled houses are based on NS 3700 [Standard Norge 2010] and an example on a passive house presented by Tor Helge Dokka and Sverre Holøs [Dokka & Holøs, 2011]. When simulating using the former insulation standard the constructions are based on the building regulations from 1997, [TEK 97] and state of the art at that time. 1. Single family house

6 Store room Walk in closet Bathroom Bathroom Living room and kitchen Living room Ground floor First floor Figure 1. Floorplan of single family house. Pink area = zone 1, blue area = zone 2, orange area = zone 3 Area of façade and windows are as shown in table 1. All windows facing south, west and east have the same solar shading consisting of external light Venetian blinds. The solar factor for closed and open blinds is 0.05 and The blinds are activated automatically when outdoor solar flux exceeds 100W/m 2. Windows to the north have no solar shading. Table 1. Fasade and window area of single family house Facing Area of facade Area of windows Zone 1 Area of windows Zone 2 Area of windows Zone 3 Total window area North South East West Sum Area of windows and doors is 19.8% of heated floor area, which is less than the limit given in TEK 10 [TEK 10]. 2. Rowhouse (not end section) Entrance Living room Store room 3.9 m2 Bathroom 4 m2 Hall 9,9 m2 Store room 3 m2 Living room Ground floor First floor Second floor Figure 2. Floorplan of rowhouse. Pink area = zone 1, Blue area = zone 2, orange area = zone 3 Table 2. Fasade and window area of row house Facing Area of Area of Area of Area of Total

7 facade windows Zone 1 windows Zone 2 windows Zone 3 window area North South Sum Area of windows and doors ( m 2 ) is 17% of heated floor area, which is less than the limit of 20% given in TEK 10 (TEK 10, 2010). The level of insulation standard is given in table 3. It also includes the insulation standard for the houses simulated with TEK 97 standard. Table 3. Basic input parameters for simulation of indoor temperatures in both house types. Building part Passive house TEK 97 Thermal bridges 0.03 W/m2K 0 (included in U-values) Leakage number, n h -1 4 h -1 U-value wall 0,09 W/m 2 K 0,22 W/m 2 K U-value roof 0,08 W/m 2 K 0,15 W/m 2 K U-value floor 0,08 W/m 2 K 0,15 W/m 2 K U-value windows 0,5 W/m 2 K 1.6 W/m 2 K U-value doors 0,7 W/m 2 K 1.6 W/m 2 K SFP-factor 1.00 kw/m 3 /s 2.5 kw/m 3 /s Efficiency factor heat exchanger Internal loads Lighting 1.95 W/m W/m 2 People 1.5 W/m W/m 2 Technical equipment 1.81 W/m W/m 2 Thermal capacity For both types of houses the inside surfaces of ceilings and walls are made of 15 mm wooden panel (thermal capacity 4.6 Wh/m 2 K) and the floor consists of 14 mm parquet on 22 mm chipboard (thermal capacity 4.6 Wh/m 2 K). The furniture in all rooms has thermal capacity of 4.0 Wh/m 2 K. Ventilation The ventilation system is a balanced system with air flow 1,2 m 3 /m 2 h. The supply air temperature is 19 deg Celsius in all months except from May till August when it is set to 12 deg Celsius in the calculations. The low supply air temperature in summer is supposed to have the same effect as the bypass function in the heat exchange unit. There is no cooling in the ventilation system so the temperature on inlet air will be slightly above outdoor temperature due to heat from the fan. We do not want the heat exchanger to add unnecessary heat to the room during summer. Simulation programme The simulations have been carried out with the programme SIMIEN. [ProgramByggerne 2010]. The programme can do yearly energy and indoor climate calculations based on dynamic calculations in 15 minutes steps. In these simulations we have focused on indoor temperature during the summer. The programme finds the dimensioning summer day, and this day can be repeated to see the influence from warm days in a row. Climate conditions As Norway spans from latitude 61 to 71 North, there is a great variation in temperature and solar radiation in different parts of the country. The climate also vary from inland to costal climate. To get some idea of geographical influence on the thermal conditions in passive houses the simulations has been done for Oslo (inland), Ålesund (costal) and for Bodø (costal and a little north of the Arctic circle).

8 Results The single family houses are first simulated without any solar shading for Oslo conditions. Outdoor temperature TEK97 zone 1 TEK97 zone 2 Passive house zone 1 Passive house zone 2 Time of day [h] Figure 3. Indoor temperatures the warmest day in Oslo for single family house with passive standard and TEK 97 standard without solar shading It is not a surprise that it becomes much too warm in houses with most windows facing south (zone 1) in Scandinavia. The reason for this is the solar height on the sky. At 12 o clock at midsummer the sun is 53.5 above the horizon in Oslo, Stockholm and Helsinki. The thick black line is at 26 C and is the upper limit for comfortable indoor temperature. From figure 3 we also see that it is too warm in rooms with less window area even when som of them are facing north (zone 2). The difference between passive house and TEK 97 house is about 1K. Of course no one wants to live in a house with these temperatures so some means must be taken to reduce the indoor temperature. Automatic solar shading is then applied to all windows except from windows facing north. The resulting temperatures then become as shown in figure 4. Time of day [h] Time of day [h] Outdoor temperature Supply air temperature Air temperature zone 1 Air temperature zone 2 Operative temperature zone 1 Operative temperature zone 2 Figure 4. Simulation with automatic solar shading. TEK 97 house left and passive house to the right. The maximum indoor temperatures are reduced to 28.5 C for both standard of insulation. It is slightly colder during the night in the house with less insulation, but in practice this is no difference. In the graph operative and air temperature is displayed, the difference is very small, but the air temperature is a bit lower during the night. This can be explained by the thermal capacity of the internal surfaces. The transmission heat loss is too small to

9 lower the surface temperatures as fast as the indoor air temperature goes down because of ventilation. Temperature of outdoor air and air supplied from the ventilation system are displayed. The inlet air temperature is about 0.7K higher in the TEK 97 house because of heat from the ventilation fan. With higher SFP-factor more energy is supplied to the air. In the rest of the paper only air temperatures are displayed. Geographical variations influence on maximum indoor temperatures The same calculations have been done with the same houses placed in Ålesund and Bodø. The maximum indoor temperature then became as shown in figure 5. Maximum temperature Oslo with solar shading Ålesund with solar shading Bodø with solar shading Oslo without Ålesund without solar shading solar shading Bodø without solar shading TEK 97 house Passive house Figure 5. Maximum indoor temperature in zone 1 at different locations As expected the overheating is reduced with lower outdoor temperatures and more wind (costal climate). The difference is not as big as one could expect. Even in Bode solar shading is required to keep the temperature down. In Oslo the indoor temperature becomes higher in the TEK 97 house than in the passive house. This can be explained by higher inlet temperature of ventilation air, more transmission gain from sunshine on the façade and roof due to lower insulation standard of walls and roof. The internal gains are also bigger for TEK 97 houses. Solar gain from windows does not differ much while using automatic solar shading. The results from zone 2 show the same trend as from zone 1, but with 1 to 2 degrees lower temperatures while using solar shading. Additional means to reduce indoor temperature during summertime. The basis for further calculations is the houses with automatic solar shading. Extra ventilation by opening windows: i.e. by opening 2 windows in each zone. The area of the openings in each zone is set to 1.1m 2. The effect of this is calculated according to the standard EN15242 [CEN, 2007] The results are given in table 4. Table 4. Maximum indoor temperatures in houses with ventilation through opened windows. TEK 97 house Passive house Zone 1 Zone 2 Zone 1 Zone 2 Maximum indoor temp. with extra window ventilation Maximum indoor temp. without extra window ventilation The indoor temperature is reduced by 0.9 K in the TEK 97 house and by 1.3 K in the passive house in Oslo. Ventilation by opening windows is more effective in passive houses than less insulated houses.

10 Equal distribution of windows on all facades were tried, but this does not make much difference on indoor temperature as long as automatic solar shading is used. The reduction of indoor temperature is less than 1 K for zone 1 for both insulation standards. The temperature will rise in Zone 2 which normally contains the bedrooms and thereby increase the problem with too warm bedrooms. Free cooling during the night with 6 m 3 /hm 2 (5 times the normal ventilation) has been tested on the basic house Zone 1 Time of day [h] Zone 2 Outdoor temperature TEK 97 with free cooling Passive house with free cooling TEK 97 Basic Passive house basic Time of day [h] Figure 6. Free cooling of single family houses in Oslo This is rather effective in Nordic climate with rather cool nights. The maximum temperature in zone 1 in passive house is reduced to 26.4 C during daytime and in zone 2 the temperature is lowered to 22 C from midnight. This is an indoor climate that will be acceptable for most people. The TEK 97 house is about 1K warmer at daytime and has the same temperature during the night. Higher thermal mass i.e. concrete floors with 14 mm parquet on top and exposed concrete in ceilings. The effect of the higher thermal mass is good in combination with freed cooling. The maximum temperatures are reduced by 2.0 K more than by just using free cooling. The effect is also here better in passive houses than in TEK 97 houses. Effects from shorter warm periods on indoor temperatures. All the results presented were based on the fifth warm day in a row. In most of Scandinavia the probability of such long warm periods are limited. The results are therefore compared for day 3 and for day 5 and result presented in figure 6.

11 Maximum indoor temperature C 3 days 5 days Zone 1 Zone 2 Zone 1 Zone 2 Passive house Figure 6. Maximum indoor temperature during day 3 versus day 5. The temperatures are significantly lower after 3 days. The effect is biggest for passive house and indicate that it take more time to warm up a very well insulated building. Row house compared to single family houses. The same calculations were done for row houses. In short the results are: the indoor temperatures in row houses are slightly higher than in single family houses. The reason for this is the reduced thermal transmission heat loss because of reduced wall and window area. The effect is largest in the night. At daytime, the temperatures are rather similar. More detailed results are presented in [Solheim 2012]. Conclusions Without solar shading all studied houses are much too warm on warm days during summer. When automatic solar shading is used, the indoor temperatures in passive houses are lower than in houses of TEK 97 standard. Efforts to lower maximum temperatures during day and night are more effective in a passive house compared to less insulated houses. Free cooling, increased thermal mass and cross ventilation by using windows are effective means to reduce overheating and creating comfortable indoor temperatures without using mechanical cooling systems. Row houses are slightly warmer than single family houses. Buildings at the coast and/or located further North experience less overheating. References [CEN, 2007] EN 15242: Ventilation for buildings Calculation methods for the determination of air flow rates in buildings including infiltration, Brussel; European Committee for Standardization, 2007 [Dokka & Holøs, 2011] Dokka, T. H. & Holøs, S.,. Inneklima og sommerkomfort i passivhus. Oslo: Passivhus [ProgramByggerne 2010] Avaliable at : http// [Solheim, 2012] Overoppvarming i passivhus samanlikna med hus med lågare isolasjonsstandard. (In Norwegian). Master theses from NTNU, Department of civil and transport engineering, [Standard Norge 2010] Criteria for passive houses and low energy houses. Residential buildings. http// [TEK 97] Forskrift om krav til byggverk 1997, (The technical building regulations) Available at

12 [TEK 10] Byggeteknisk forskrift 2010, (The technical building regulations) Available at

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