128 LOWEX GUIDEBOOK

CASE STUDIES - BREGENZ- ART MUSEUM

BREGENZ, AUSTRIA

PROJECT DESCRIPTION

Building type residential, office, school, otherotherotherotherotherHeating generation boilerboilerboilerboilerboiler,,,,, central heat pump, DH, solar, cogeneration, otherHeating emission radiators/convectors, floorfloorfloorfloorfloor, wall, , wall, , wall, , wall, , wall, ceiling,ceiling,ceiling,ceiling,ceiling, airCooling generation heat pump, DC, otherotherotherotherotherCooling emission radiators/convectors, floorfloorfloorfloorfloor, wall, ceiling,, wall, ceiling,, wall, ceiling,, wall, ceiling,, wall, ceiling, airStorage storage tank,storage tank,storage tank,storage tank,storage tank, aquifer, other

The incredibly self-confident, calm

presence of the House of Art

rooms stacked one above the

other - with their sensitive, natural

lighting - would be inconceivable

had the architect not come across

the new, and at the time still

scarcely known, heating and

cooling system with thermoactive

components during development

of his draft design.

The four storey building has a double skinexternal envelope with an outer openedglass wall. In the original design an airconditioning system with 25 000 m³/h airwas planned. Due to difficulties in gettingspace for the ducts and the visibility of theducts between the glass ceiling and theconcrete slab another solution was needed.The requirements of high level stability ofroom temperature and relative air humiditybrought further challenge to the duty. Thehigh energy demand and high level of noiseemissions of conventional air-conditioningsystems called for a new solution. In this artmuseum the space heating is provided witha hydronic system embedded in thebuilding structure. In addition, two-zonedisplacement ventilation provides a minu-mum of outside air.

GENERAL DATAPrincipal: Land VorarlbergArchitect: Peter ZumthorConstructor:Installer:Energyconcept: Meierhans & Partners,

and J. BohleHand-over: Opened in July 1997

BUILDING DATABuilding envelope: U (W/m2K)facade double skinrooffloorglazingAir tightness:Volume: 28 000 m3

Surface area: 3 340 m²Specific heat load:Specific cooling load:

AUT 1AUT 1AUT 1AUT 1AUT 1

129EXAMPLES OF LOWEX BUILDINGS

GENERAL DESCRIPTIONThe fully integrated soft HVAC-technolo-

gy for this special building is based on afurther development of concrete corecooling which had been developed for anoffice building a few years previously inclose co-operation with th architect and histeam (Meierhans 1996). The concrete,visible everywhere, enables dynamiccoupling of room climate to water-cooled

and heated walls and ceilings. The ventila-tion system no longer has to perform thetasks of heating and cooling - its onlyfunction is that of air renewal. The heatingand cooling process is carried out using thethermoactive building mass. It is thereforefully integrated in both senses of the word,because not only are the room climate andthe building mass coupled actively andpassively, but also because it has been

INSTALLATION SCHEME

Museum in Bregenz with pipes embed-ded in walls and concrete slabs forheating and cooling. Details show thedisplacement ventilation and thegeneration system for cooling andheating.

DESCRIPTION OF INSTALLATIONS

130 LOWEX GUIDEBOOK

possible to accommodate all peripheralclimatic components in the load-bearingbuilding structure. This did not involve theusual compromise of concealing a neces-sary evil, but rather the integration of asimilarly minimised, but clearly arrangedinfrastructure.

Finely branched air supply pipes were setin concrete in the ceilings in stead of largesupply and exhaust ducts covered bysuspended ceilings. There is not a singleplace where an air duct or heating pipecould be hidden behind a screen or asuspended ceiling.

EXPERIENCES - MEASUREMENTS

COMFORTThe number of visitors had been severely

underestimated (estimated 250 visitors/dayvs. 1 000 visitors/day in reality). Theguaranteed values are however satisfiedwithout any problems during normaloperation of the museum (Figures AUT 1.1and AUT 1.2).

ENERGY USEThe energy and operation costs are more

than 50 % lower in comparison with otherfully air-conditioned art museums.

Figure AUT 1.1. Measurements of temperature and relative humidity in October 1997.

OCCUPANTSSome members of the staff found that

the maximum summer room temperature,which had been set to 26 °C, was unpleas-antly high under the conditions of high airhumidity required for the exhibits. Themaximum value was lowered.

EXPERIENCES - USERS

Figure AUT 1.2. Temperature readings in April 2000. Air temperature 0.1 and 3.0 meter abovefloor together with floor surface temperature.

OVERVIEWHeat generation:

Condensing gas boilerCooling generation:

Plastic pipes in concretefoundations and pillars

Emission system:Concrete slab cooling inceilings and walls, 28 000 m ofplastic pipes

Costs of heat emission system:Total heating, cooling andventilation system 1 000 000 €compared to first planned full AirConditioning 2 000 000 €

DHW:Ventilation:

Displacement, 750 m³/h pr. floor

LITERATURE

Meierhans, R., Olesen, B.W. 2002.House of Art in Bregenz -Soft HVAC for aStrong Architecture. ASHRAE-Transactions-2002, Part 2.