Part 4

Question 1

A spectrum of building retrofits

Answer 1

1- energy efficiency retrofits.
2- water conservation retrofits.
3- indoor air quality retrofits,
4- accessibility retrofits.

Question 2

Energy efficiency retrofits focus on:

Answer 2

• improving building envelope, walls, windows, roof.
• upgrading mechanical systems, hvac, lighting to reduce consumption.
• change or improve ligpfe and behaviour patterns

Question 3

Water conservation retrofits

Answer 3

• low flow fixtures.
• repairing leaks.
• capturing rainwater.

Question 4

Indoor air quality retrofits

Answer 4

• improve ventilation.
• remove pollutants.
• controlling moisture.

Question 5

Accessibility retrofits

Answer 5

• widening doorways.
• installing ramps.
• lowering counters,

Question 6

Core retrofit bundles

Answer 6

Core EE technologies applied together as a bundle, have to use them, reduce total energy by 50%
لا يمكن الاستغناء عنهم
Some of them are calculated depending on modeling results, some based on country codes and some by practice.
Insukation, windows, doors, thermal bridges, airtightness, vapor barrier, building envelope, lighting, controls, hvac, heat recovery ( building envelope, lighting and electrical system, HVAC).
Maybe not enough, can add more technologies

Question 7

Core technologies bundle include

Answer 7

• insulation of walls, roofs, slabs.
• windows and doors high performance.
• mitigatimg thermal bridges,
• improve airtightness and vapor control.
• omplementation o building envelope retrofits.

Question 8

Thermal insulation

Answer 8

Insulation type and thermal performance should be evaluated at initial energy audit.

Question 9

Insulation type and location depend on different factors:

Answer 9

1- building typology and considerations.
2- local climate.
3- building structure and existing fabric
4- building height.
5- fire code requirements.

Question 10

Location of insulation

Answer 10

1- internal insulation.
2- cavity insulation.
3- external insulation.
4- combination

Question 11

Internal insulation advantages

Answer 11

Does not change appearance of building
Cheap to install
Only possibility for historic buildings.

Question 12

Internal insulation disadvantages

Answer 12

Cause incinvenience to occupants dust, noise
Reduce usable area.
Moisture priblems, mold growth.
Cold bridges,
Bathrooms and kitchens cannot be insulated, high costs.

Question 13

External insulation advantages

Answer 13

Relatively sensitive to workmanship
No risk of moisture problems.
Work can be done with little inconvenience to occupants.
Peotect the structure of the building from temp fluctucations

Question 14

External insulation disadvantages

Answer 14

Changed appearance
Requires space around building
Extensive works are often needed.

Question 15

Windows and femestration energy performance parameters

Answer 15

1- thermal transmittance.
2- solar heat gain coefficient (shgc or g).
3- air leakage.
4- optical properties.

Question 16

Thermal transmittance

Answer 16

U value, lower u value is better.
A measure of fenestration products heat transfer due to temperature difference between inside and outside.

Question 17

SHGC

Answer 17

Measure of fenestration product or system ability to transmit or reject incident solar radiation, minimum is better, vary with climate severity.

Question 18

Air leakage

Answer 18

Measure of window or fenestration system resistance to air flow from wind and driving forces, expressed in l/min.m2
Solution: thermal breakers in aluminum frame.
Affected by air movement not climate

Question 19

Optical properties

Answer 19

Substrates, substrate coating, or both which affect specific wavelengths of solar light ( visible transmittance)

Question 20

Visible transmittance

Answer 20

Measure of how well the fenestration system transmits solar energy in the visible portion of asolar spectrum.
Internal, external.

Question 21

Shading coefficient

Answer 21

External reflectance, from outside enters inside, close to 1 means less reflectance
Internal reflectance, from inside to outside.

Question 22

Optical coating

Answer 22

Thin layers of oxides or metals deposited onto optical components like mirrors or filters, these coatings influence how light interacts with the component.

Question 23

Optical coating types

Answer 23

1- anti reflective ar coating: reduce reflections by minimizing the difference in refractive index between air and the coated surface. بتقلل glare
2- highly reflective dielectric coatings: create mirrors by maximizing reflectivity at specific wavelengths. زي النضارة الي بتصير شمسية
3- enhanced transmission coatings: these coatings selectively enhance the transmission of specific wavelengths. الزجاج الملون
4- polarizing coatings: selectively transmit light with specific polarization orientation.

Question 24

Design parameters for windows selection

Answer 24

1- building orientation.
2- window to wall ratio
3- window to floor ratio.
4- access to daylight and view.