1. PASSIVE HOUSE VENTILATION SYSTEMS
Patricia Alonso Alonso LECTURER
Department of Building Constructions

2. Why do buildings need to be ventilated?

3. Because we……………………………………………………..
…..…..….………………..reduce heat gain in summer
..reduce moisture and condensation in winter
…………..keep people healthy and comfortable

4. PASSIVE HOUSE VENTILATION SYSTEMS
FOR DESIGN………………………………………………...
INTRODUCTION
CONCEPTS & TECHNIQUES
SYSTEMS
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

5. PASSIVE HOUSE VENTILATION SYSTEMS
FOR DESIGN………………………………………………...
INTRODUCTION
CONCEPTS & TECHNIQUES
SYSTEMS
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

6. Thermal comfort sensation
Temperature
Season
Temperature (ºC)
Summer
23….25
Winter
21….23
Data table: temperature and thermal comfort
CONCEPTS
& TECHNIQUES
SYSTEMS
CONCLUSIONS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING

7. Thermal comfort sensation
Data table: Relative humidity and thermal comfort
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

8. Thermal comfort sensation
Warmth feeling is reduced using air movement 1ºC less for 0,2 m/s velocity increased. Limit: 5ºC
Velocity
(m/s)
Sensation
Until 0,2
inappreciable
0,2 to 0,5
Nice, but air movement is perceved
0,5 to 1
Mild discomfort to severe discomfort
1 to 1,5
Unfit for human comfort
>1,5
Corrective action is required
Data table: Air velocity and comfort sensation. Source:
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

9. Comfort sensation Air quality “Sick building Symdrome” SYSTEMS
Source: (Araujo, 2009)
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

10. PASSIVE HOUSE VENTILATION SYSTEMS
INTRODUCTION
CONCEPTS & TECHNIQUES
SYSTEMS
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

11. Source: (Helena Granados, 2006)
CONCEPTS
Natural ventilation without any mechanical device
Difference between two points
“Chimmey or Stack effect”
The higher temperature difference , the better natural ventilation
Source: (Helena Granados, 2006)
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

12. Source: (Helena Granados, 2006)
2. Decrease in pressure over extraction point “Venturi effect” The higher wind velocity and little extraction gap size, the better natural ventilation.
Source: (Helena Granados, 2006)
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

13. 3. Dynamic pressure generated by the wind over a hole “Wind effect” The higher wind velocity, the pressure generated and difference of pressure with respect of other hole, the better of the ventilation.
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

14. Source: (Helena Granados, 2006)
TECHNIQUES IN BUILDINGS
Pure natural ventilation
The simplest form of ventilation is window opening (shape, side and position in relation to each other)
-Direct (Effectiveness: The depth of the room should not exceed 2,5 times the room height)
-Cross-ventilation (Effectiveness: The depth of the room should not exceed 5 times the room height)
Cross-ventilation
Direct H
2,5 or 5 H
Source: (Helena Granados, 2006)
Source: (Helena Granados, 2006)
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

15. B. Naturally forced ventilation (utilising updraught systems)
(Effectiveness: air pressures decreases with increasing height. Warm air has a lower density than cold air)
Reheating façade
Reheating roof
Heat chimmey extraction
Wind chimmey induction
Elevated atria
Reheating façade
Reheating roof
Source: (Neila,2009)
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

16. Updraught systems Extraction at wet areas.
Heat chimmey extraction
Source: (Neila,2009)
Source: (Araujo,2009)
CONCEPTS
& TECHNIQUES
SYSTEMS
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS
INTRODUCTION

17. Elevated atria SYSTEMS Source: (Araujo, 2009) CONCEPTS & TECHNIQUES
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

18. PASSIVE HOUSE VENTILATION SYSTEMS
INTRODUCTION
CONCEPTS & TECHNIQUES
SYSTEMS
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

19. PASSIVE COOLING SYSTEMS FOR BUILDINGS
Evaporative cooling
Vegetation and water
Air and water
Radiant cooling
Wet roofs
Courtyards
Conductive cooling
Cold surfaces
Underground ducts
Underground constructions
Convective cooling
Night ventilation
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

20. Source: (Helena Granados, 2006)
EVAPORATIVE COOLING
It is a adiabatic process
The overall energy is not altered
Water:
To a good evaporation it is necessary to achieve a high spraying level
The best: a water jet
Worse: a water pond
Source: (Helena Granados, 2006)
Source: (Neila, 2009)
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

21. Source: (Helena Granados, 2006)
Vegetation:
A tree is capable of evaporating 500 Kg of water/year every m2 of exterior surface.
That means 1212MJ/m2 a year that is equivalent to a cooling power of 40W/m2 of vegetal surface
Source: (Helena Granados, 2006)
Source: (Neila, 2009)
CONCEPTS
& TECHNIQUES
SYSTEMS
CONCLUSIONS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING

22. Source: (Helena Granados, 2006)
Water and vegetation:
To evaporate 1 gram/s of water (it
is necesary 2424 Julius/s or 2,42kW cooling power) it is reduced 2,2ºC
the temperature of a m3 air
Example:
Alhambra de Granada
Source: (Helena Granados, 2006)
Source: (Neila, 2009)
CONCEPTS
& TECHNIQUES
SYSTEMS
CONCLUSIONS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING

23. Source: (Helena Granados, 2006)
Air:
Popular architecture of Middle East:
Wind towers “Malqaf”
or windcatchers
Source: (Helena Granados, 2006)
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

24. Water and air: Windcatchers with evaporative cooling effect
Sample of Malqaf using Salsabil (fountain), (Hassan Fathy 1986)
Section of Malqaf using Pottery Jars to cool Air at Maziara Egypt by Hassan Fathy (Rosa Schiano 2007)
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

25. Water and air: Windcatchers with evaporative cooling effect
Bahadori (1985) developed the Downdraught Evaporative Cool Towers as an upgrade to the traditional Malqaf & Badgir
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

26. Source: (Rosa Schiano 2007)
Water and air:
Mashrabiya. Muscatese Evaporative cooling window system.
Source: (Rosa Schiano 2007)
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

27. Water and air: Recent example: Spanish Pavilium. Zaragoza 2008 (Spain)
Patxi Mangado Architect
Based on “Botijo” effect
(Porous water pot)
Source: Mercadel, 2014
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

28. Spanish Pavilium. Zaragoza 2008 (Spain) Patxi Mangado Architect
Source: (Mangado, 2009)
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

29. RADIANT COOLING
When the cooling system is reducing the quantity of energy of an environment it is named sensitive cooling.
Two things we need:
A bit of cold and mass enough to dump the heat and maintaining the temperature.
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

30. Source: (Helena Granados, 2006)
Types of heat sinks to radiate: Celestial dome that covers us The ground that supports us The air that surrounds us The water Types of radiant mass at buildings Radiant slabs and ceilings Wet roofs Façade Courtyards
Source: (Helena Granados, 2006)
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

31. Source: (Helena Granados, 2006)
Radiant slab and ceiling
Wet roofs
Water confined in black bags and set on the roof
“Roof pond”
Source: (Helena Granados, 2006)
CONCEPTS
& TECHNIQUES
SYSTEMS
CONCLUSIONS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING

32. Façade: Trombe-Michel walls, (Northwest of Spain)
Source: (Helena Granados, 2006)
Constructive detail of a “galería”
Typical galería of A Coruña (Spain)
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

33. Source: (Helena Granados, 2006)
Courtyards:
Cooling effect over night radiation
Outside air temperature should be 5K below the inside room temperature for at least 5 to 6 hours
Source: (Helena Granados, 2006)
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

34. Underground buildings. Cave dwelling
CONDUCTIVE COOLING
Underground buildings. Cave dwelling
About nine meters underground the temperature is steady.
Plan of a cave dweling at Guadix, Granada (Spain)
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

35. Cave dwelling Guadix, Granada (Spain)
Ventilation chimmey of caves
Typical plan of a cave
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

36. Source: (Helena Granados, 2006)
Underground ducts
Duct under the ground passing an airstream and then pushing up to the building interior. Earth pipes
Example:
“Canadian well”
Source: (Helena Granados, 2006)
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

37. CANADIAN WELL
Geothermal system where the stability of the temperatures of underground are used to improve the air temperature before entering in buildings (underground in winter the temperature is higher and in summer is less than in outside), providing freshness in summer and warmth in winter.
Ducts are buried between 1.5 and 3 m the long of ducts are between 10 and 100 m. Airstream pass through this ducts therefore it is heated or cooled before pushing up to building interior.
Typical diameter of an earth pipe is 20cm
Ducts are buried between 1.5 and 3 m
Ducts length are between 10 and 100 m
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

38. Source: (Eco-house system website, 2014)
The distance between them should not be less than one metre
A low velocity of 2m/s should be ensured
Between temperatures 12-18ºC the earth-pipe is not usually used
A Canadian well can reduce the temperature by 5 to 8°C in your house during a heat wave using virtually no electricity
Source: (Eco-house system website, 2014)
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

39. Typical ventilation installation of Standard Passive house
Source: (Wikipedia, 2014)
CONCEPTS
& TECHNIQUES
SYSTEMS
CONCLUSIONS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING

40. Passive house standards with heat recovery ventilation system (HVR)
Source: (Araujo, 2009)
Source: (Araujo, 2009)
CONCEPTS
& TECHNIQUES
SYSTEMS
CONCLUSIONS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING

41. Spanish Building Code C.T.E. DB-HS-3 Interior Air Quality
Centralized ventilation
Humidity sensor
Spanish Building Code
C.T.E. DB-HS-3
Interior Air Quality
Proposed solution
(Comunidad de Madrid)
Night cooling is very efficient
Minimum maintenance
Very interesting in refubishing
Individual ventilation
unit
Intelligent
CO2 sensor
Source: (Fenercom, 2014)
CONCEPTS
& TECHNIQUES
SYSTEMS
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS
INTRODUCTION

42. Source: (Helena Granados, 2006)
CONVECTIVE COOLING
Using cold mass of air.
Night ventilation
Example: Villa Costozza in Italy, Andrea Palladio
Source: (Helena Granados, 2006)
CONCEPTS
& TECHNIQUES
SYSTEMS
CONCLUSIONS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING

43. PASSIVE HOUSE VENTILATION SYSTEMS
INTRODUCTION
CONCEPTS & TECHNIQUES
SYSTEMS
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

44. CONCLUSIONS HOW TO PROCEED?……………………………………………..
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

45. 1. We should analize very vell the environment and socio-economical and local aspects 2. We could select different VENTILATION strategies to apply at Corte, Corsica 3. We could try to develop a diagram of how it would work 4. We could develop the solutions selected
CONCEPTS
& TECHNIQUES
SYSTEMS
INTRODUCTION
EVAPORATIVE COOLING
RADIANT COOLING
CONDUCTIVE COOLING
CONVECTIVE COOLING
CONCLUSIONS

46. For example……………………………………………………………..
Steps to analize building constructions
Source: (Neila, 2004)
1. Location
2. Climate
3. Environmental conditions
4. Socioeconomic conditions
5. Formal description
6. Constructive description
7. Environmental use and bioclimatic strategies

47. ……………the next step is your decision

48. PASSIVE HOUSE VENTILATION SYSTEMS Thank you for your attention
*All this information and images exposed are been used only for educational purposes
Patricia Alonso Alonso LECTURER
Department of Building Constructions