ECO-DESIGN

BIO-CLIMATIC DESIGN

CONCEPTS

• Building Orientation and Form
•  Building Envelope and Materials
•  Integration of Renewable Energies
•  Green Roofs
•  Water
•  Daylight Strategies

Building orientation and form

Objectives:

- the reduction and control of solar radiation;

- the provision of natural ventilation and natural cooling of the

external building surfaces by evaporative cooling.

Actions:

- minimize the surface area of the south facing facade;

- at the same time provide for natural lighting and shading;

- avoid excessive solar gain during the cooling season;

- use the roof as an active skin.

It is important to consider the local

climate during the first stage of

building design.

An energy conscious design which

results in an energy efficient

building has to be based on the

local climate.

In a new hospital, the shape and

the orientation of the building

should be first defined considering

the climate of the area, the wind,

the temperature and the solar

radiation.

It should be decided which areas

of the hospital need more solar

exposure and which hospital areas have a high internal heat load

and need less solar exposure. The aim is the reduction of the

annual energy demand.

It is important to balance the various requirements. Patient comfort

is clearly of paramount importance. Environmental impacts, energy

consumption and aesthetics are also important but the primary aim

when designing a new hospital should not be reducing the energy

demand to zero. Nor should the form of the building be considered

only in terms of the aesthetic result.

The section view of the Meyer Hospital shows that it has been

designed partly sunk into the hill. This diminishes the impact of the

building on the site and contributes to energy conservation by

providing shelter so that the hospital is shielded from the prevailing

winds by the hill and the trees.

During the design of the building effort was focused on detailed

planning and the design of the health care environment. The

psychological effects of the environment were taken into careful

account. This approach was considered essential for the neonatal

intensive care environment and its effect on babies, their families

and carers.

Building envelope and materials

Glazing and Double Skin Facade

A building has to guarantee a thermally

comfortable indoor environment for the

activities that are conducted inside. To

optimise thermal comfort it is necessary

to reduce the loss of thermal energy

through the building envelope.

A Double Skin Facade is an additional

external skin for a building that can

optimize the indoor climate and reduce

the energy demand of the building. The

brochure Double Skin Facade Design is

available for details.

The building envelope of the new

hospital building at Fachkrankenhaus

Nordfriesland has been designed with

high insulation levels and with special

attention paid to the windows.

There is a double skin facade with

windows which can be opened in the

inner skin, parts of the outer skin or

both. The windows are designed as

sources for supplementary venting and

daylighting as well as visual comfort.

Building materials have been very carefully selected, particularly

the materials exposed inside the building as these will affect the

indoor air quality.

The selection of building materials was based on criteria for:

emissions, adsorption, surface roughness and cleaning.

There will not be any PVC materials used within the building and

the use of metals is kept to a minimum.

The innovative elements of the building envelope and materials are

summarised below:

- Transparent insulation

- Glazing with reduced U-values

- Double skin facades

- Selection of low-emission and

low adsorption materials

Wall insulation

Energy losses are normally stated in terms of heat flow through a

square meter of wall per unit of time. The losses depend mainly on

the temperature difference between the inside and outside face of

the wall and the thermal resistance of the material, or combination

of materials, from which the wall is made.

Energy losses take place through conduction,

convection and radiation. The main way of

reducing losses is to prevent heat conduction by

adding thermal insulation to the envelope.

Cavity insulation: This is an inexpensive way

of insulating a wall but it can only be used when a

cavity wall is present. Retrospective insulation of

the cavity can occasionally create problems.

Inspection of the walls is recommended before a

decision is made to insulate a cavity.

Retrospective insulation of a cavity wall can be

done by injecting expanded clay granules, mineral

wool flakes or polystyrene beads through a hole

into the cavity.

External insulation: This changes the

appearance of the exterior considerably. A single,

thick insulation layer can be applied, which makes

it possible to achieve any desired insulation value.

The main advantage is that cold bridges can be

easily removed and prevented.

Internal insulation: This is fitted on the inside

of the walls of a building. The size of the rooms is, of course,

reduced by internal insulation. Inside insulation can give good

results when it is carefully executed in order to prevent

condensation caused by cold bridges.