IRD: advanced principles and
performance
Integrated Regenerative design = climate design, regenerative cities + building technology,
engineering
Skin is often the key aesthetic expression of the building and plays an important role in
sustainability strategy of the building
Requirements, Performance and Characteristics that are commonly expected from a newly
designed envelope.
THE SKIN: DEFINITION
It’s the outer covering of the body, building or structure. It is the largest organ of a system. In
architecture, it protects the interior from external in uences or from being overlooked.
THE SKIN: FUNCTION: TRADITIONAL/PRIMAR FUNCTIONS
Shelter function: physical border between outside-and inside, enclosing and protecting a V
Protection function: protect from T, moisture, incidence ( re and security)
Social function: giving character, creating interactions, providing accts and views
Health function: ventilating, allowing light to enter
> the facade must open up the outside world, interact with it and admit air and light. Openings
link the inside and the outside functionally and/or visually.
THE SKIN: FUNCTION: ADVANCED FUNCTIONS
Resilience function: adaptable, interchangeable and replicable when obsolete (when old)
Resilience function: repairable, maintainable to extend life cycle
Resilience function: robustness against mechanical aggression and wear
Resilience function: longevity against UV radiation
Health function: provides quietness, acoustical insulation and absorption
Health function: immunity against pathogens and contaminants, material hazardousness
Connectivity function: acting as a sensory organ and informing building management systems,
use of sensor in building skins
Advanced principles and performance 1 of 3
fl fi
, THE SKIN: REQUIREMENTS/FUNDAMENTALS AND PERFORMANCES (HIERAAN VOLDOEN)SSW
Wind loads
Forces exerted by window the exterior surfaces of buildings
Factors that in uence wind pressure: geographical location, H of bld, terrain roughness,
orientation of facade and service lifespan
Watertightness
Capacity of a facade to remain watertight under a certain water pressure
Thermal transmittance = U value (W/m2K)
= thermal insulation: rate of transfer of heat through a material or buildup, divided by the
di erence in T across the structure
U ↘︎ > insulation is better
R-value = thermal resistance: R = 1/U
Min U value of an opaque wall in BE? > 0,24 W/m2K
U value of an opaque wall of well insulated building in BE? > 0,16 W/m2K
Vapor tightness (vocht)
Moisture -safe construction relies on understanding how moisture moves within the
building, summer and winter
Buildings don’t need to be vapour tight! In mild or cold climates: each layer that composes
the shell or skin needs to be more vapour permeable than the layer inward
Water vapor resistance of a material = Sd value = the resistance to the movement of water
vapor to that of a meter of air
Sd value ↖︎ > the higher resistance
Sd value ↘︎ > the lower the resistance (breathable membrane)
Airtightness
related to:
Energy e ciency: air leakage > ↖︎ heat loss and gain the energy required to
maintain a stable indoor T. When air in ltrates in the building enveloppe, it
bypasses the thermal insulation layer, reducing the e ectiveness of the thermal
insulation
Indoor comfort: leaks lead to discomfort due to air drafts, hot spots. Airtight
building enveloppe helps reducing uctuations in indoor T increasing thermal
comfort. Air-leaky allows external pollutants, allergens, contaminants to enter.
Constructions integrity and longevity: leaking air moving > carry moisture. When
moisture encounters cold surfaces, it can condense, leading to water damage,
mold growth and structural decay.
how to measure: blower door test: measures the rate at which air leaks through the bld
envelope
Air permeability: q50 (m³/(m²·h)).
Air change rate: n50 (h⁻¹), indicates how many mes the air within the building is replaced
per hour at a pressure di erence of 50 Pascals2
Construction with high level of attention to airtightness detailing = n50 <0.4/h
Current code in Brussels for new tertiary buildings = n50 <0.6/h
Current code in Brussels for new residential buildings = n50 <0.8/h
Average Brussels o ce building 10 to 20years old: n50 <2,2/h
Average unrenovated residential building in Brussels: n50 ≈ 7,8/h
Inertia
Helps stabilise indoor temperatures by absorbing excess heat during the day and
releasing it at night. It can reduce the need for active heating or increase
dense materials have higher thermal inertia > store a lot of E and help dampening the
e ects of external T swings
Dark coloured and texture surfaces can increase a material’s ability to absorb and release
heat, optimising thermal performances
Contribution to overheating
Solar heat gains are the increase in T within a building due to solar radiation entering
through windows, walls, roofs
Solar heat gains should be maximized in winter and minimize them in summer > few
shading devices: blinds, trees, awnings
G-value = heat gain coe cient: amount of solar radiation passing through materials: direct
transmissions and absorbed and re-radiated by the glazing
Advanced principles and performance 2 of 3
ffff fl ffi ffi ffi ff fl fi ff
, G-value: 0 means no solar heat gain - 1 means maximum heat gain > depends on
glazing
Daylight quality
Enhance aesthetic and psychological well-being of people
Reduces reliances on arti cial light > more E
Arti cial light converts electrical energy to light, but during that process a big
amount of E is also converted into heat
Contribution to heat island e ect
Buildings, roads, other infrastructure absorb and re-emit sun’s heat (more then natural
landscapes like forest and water bodies). Urban areas = islands of higher T
Building skin materials are often designed to re ect solar radiations > keeps heat out of
buildings, but also contributes to urban heat island e ect by re ecting heat onto other
materials that absorb it (feg pavement)
Through e ect of inertia night T of urban environment could be increased by HIE >
reduces the passive night cooling systems
Quality of views
The quality of views towards the landscape, provided by openings in the building
envelope, signi cantly contributes to the wellbeing of building users. These views o er
aesthetically appealing scenery, play a crucial role in orientation, and provide information
about the weather and time of day. They help alleviate stress by allowing occupants to
frequently change the focus distance of their eyes and enjoy a change of scenery.
Additionally, high-quality views help prevent the early obsolescence of the building’s
exterior
Acoustics: mass, mass spring mass, asymmetry
Ecosystems
Fire prevention resistance and reaction
Maintenance and security
Maintenance
Reduce Maintenance Needs: Choose appropriate materials that resist UV radiation,
temperature uctuations, and porosity issues.
Design Safe Access Points: Plan for easy and safe access for cleaning, repairs, and
inspections.
Modular Design: Designing the facade in modular sections allows for easier replacement
or repair of damaged parts without disturbing the entire structure.
Security
Safety of building users: handrails, laminated glass, etc.
Safety of public space users: Durability of sealants and glues, Corrosion Resistance of
anchors
THE PRINCIPLES OF FACADES
1) LOAD BEARING FACADE
2) SELF-SUPPORTING ENVELOPES
3) NON-SELF SUPPORTING ENVELOPES
4) HEAVY VS LIGHT FACADES
Advanced principles and performance 3 of 3
fffi fl fi ff fi fl ff fl ff
performance
Integrated Regenerative design = climate design, regenerative cities + building technology,
engineering
Skin is often the key aesthetic expression of the building and plays an important role in
sustainability strategy of the building
Requirements, Performance and Characteristics that are commonly expected from a newly
designed envelope.
THE SKIN: DEFINITION
It’s the outer covering of the body, building or structure. It is the largest organ of a system. In
architecture, it protects the interior from external in uences or from being overlooked.
THE SKIN: FUNCTION: TRADITIONAL/PRIMAR FUNCTIONS
Shelter function: physical border between outside-and inside, enclosing and protecting a V
Protection function: protect from T, moisture, incidence ( re and security)
Social function: giving character, creating interactions, providing accts and views
Health function: ventilating, allowing light to enter
> the facade must open up the outside world, interact with it and admit air and light. Openings
link the inside and the outside functionally and/or visually.
THE SKIN: FUNCTION: ADVANCED FUNCTIONS
Resilience function: adaptable, interchangeable and replicable when obsolete (when old)
Resilience function: repairable, maintainable to extend life cycle
Resilience function: robustness against mechanical aggression and wear
Resilience function: longevity against UV radiation
Health function: provides quietness, acoustical insulation and absorption
Health function: immunity against pathogens and contaminants, material hazardousness
Connectivity function: acting as a sensory organ and informing building management systems,
use of sensor in building skins
Advanced principles and performance 1 of 3
fl fi
, THE SKIN: REQUIREMENTS/FUNDAMENTALS AND PERFORMANCES (HIERAAN VOLDOEN)SSW
Wind loads
Forces exerted by window the exterior surfaces of buildings
Factors that in uence wind pressure: geographical location, H of bld, terrain roughness,
orientation of facade and service lifespan
Watertightness
Capacity of a facade to remain watertight under a certain water pressure
Thermal transmittance = U value (W/m2K)
= thermal insulation: rate of transfer of heat through a material or buildup, divided by the
di erence in T across the structure
U ↘︎ > insulation is better
R-value = thermal resistance: R = 1/U
Min U value of an opaque wall in BE? > 0,24 W/m2K
U value of an opaque wall of well insulated building in BE? > 0,16 W/m2K
Vapor tightness (vocht)
Moisture -safe construction relies on understanding how moisture moves within the
building, summer and winter
Buildings don’t need to be vapour tight! In mild or cold climates: each layer that composes
the shell or skin needs to be more vapour permeable than the layer inward
Water vapor resistance of a material = Sd value = the resistance to the movement of water
vapor to that of a meter of air
Sd value ↖︎ > the higher resistance
Sd value ↘︎ > the lower the resistance (breathable membrane)
Airtightness
related to:
Energy e ciency: air leakage > ↖︎ heat loss and gain the energy required to
maintain a stable indoor T. When air in ltrates in the building enveloppe, it
bypasses the thermal insulation layer, reducing the e ectiveness of the thermal
insulation
Indoor comfort: leaks lead to discomfort due to air drafts, hot spots. Airtight
building enveloppe helps reducing uctuations in indoor T increasing thermal
comfort. Air-leaky allows external pollutants, allergens, contaminants to enter.
Constructions integrity and longevity: leaking air moving > carry moisture. When
moisture encounters cold surfaces, it can condense, leading to water damage,
mold growth and structural decay.
how to measure: blower door test: measures the rate at which air leaks through the bld
envelope
Air permeability: q50 (m³/(m²·h)).
Air change rate: n50 (h⁻¹), indicates how many mes the air within the building is replaced
per hour at a pressure di erence of 50 Pascals2
Construction with high level of attention to airtightness detailing = n50 <0.4/h
Current code in Brussels for new tertiary buildings = n50 <0.6/h
Current code in Brussels for new residential buildings = n50 <0.8/h
Average Brussels o ce building 10 to 20years old: n50 <2,2/h
Average unrenovated residential building in Brussels: n50 ≈ 7,8/h
Inertia
Helps stabilise indoor temperatures by absorbing excess heat during the day and
releasing it at night. It can reduce the need for active heating or increase
dense materials have higher thermal inertia > store a lot of E and help dampening the
e ects of external T swings
Dark coloured and texture surfaces can increase a material’s ability to absorb and release
heat, optimising thermal performances
Contribution to overheating
Solar heat gains are the increase in T within a building due to solar radiation entering
through windows, walls, roofs
Solar heat gains should be maximized in winter and minimize them in summer > few
shading devices: blinds, trees, awnings
G-value = heat gain coe cient: amount of solar radiation passing through materials: direct
transmissions and absorbed and re-radiated by the glazing
Advanced principles and performance 2 of 3
ffff fl ffi ffi ffi ff fl fi ff
, G-value: 0 means no solar heat gain - 1 means maximum heat gain > depends on
glazing
Daylight quality
Enhance aesthetic and psychological well-being of people
Reduces reliances on arti cial light > more E
Arti cial light converts electrical energy to light, but during that process a big
amount of E is also converted into heat
Contribution to heat island e ect
Buildings, roads, other infrastructure absorb and re-emit sun’s heat (more then natural
landscapes like forest and water bodies). Urban areas = islands of higher T
Building skin materials are often designed to re ect solar radiations > keeps heat out of
buildings, but also contributes to urban heat island e ect by re ecting heat onto other
materials that absorb it (feg pavement)
Through e ect of inertia night T of urban environment could be increased by HIE >
reduces the passive night cooling systems
Quality of views
The quality of views towards the landscape, provided by openings in the building
envelope, signi cantly contributes to the wellbeing of building users. These views o er
aesthetically appealing scenery, play a crucial role in orientation, and provide information
about the weather and time of day. They help alleviate stress by allowing occupants to
frequently change the focus distance of their eyes and enjoy a change of scenery.
Additionally, high-quality views help prevent the early obsolescence of the building’s
exterior
Acoustics: mass, mass spring mass, asymmetry
Ecosystems
Fire prevention resistance and reaction
Maintenance and security
Maintenance
Reduce Maintenance Needs: Choose appropriate materials that resist UV radiation,
temperature uctuations, and porosity issues.
Design Safe Access Points: Plan for easy and safe access for cleaning, repairs, and
inspections.
Modular Design: Designing the facade in modular sections allows for easier replacement
or repair of damaged parts without disturbing the entire structure.
Security
Safety of building users: handrails, laminated glass, etc.
Safety of public space users: Durability of sealants and glues, Corrosion Resistance of
anchors
THE PRINCIPLES OF FACADES
1) LOAD BEARING FACADE
2) SELF-SUPPORTING ENVELOPES
3) NON-SELF SUPPORTING ENVELOPES
4) HEAVY VS LIGHT FACADES
Advanced principles and performance 3 of 3
fffi fl fi ff fi fl ff fl ff
