Architecture Technologhy

Technology 03 is about the design of healthy, comfortable and delightful indoor environments. We will explore the forces that influence human health, comfort and delight in the built environment – and influence architectural form.

Internal Loads: people, lights and equipment

Sound: room acoustics and noise isolation

Systems: mechanical systems for heating, cooling, lighting, power, communication, plumbing, fire protection, and conveyance.

ARCH 3200/8250 Large, internal-load dominated buildings whose thermal conditions are dominated by

INTERIOR FORCES:

Daylighting/ Electric Lighting Maximize Visual Comfort – Reduce Energy Use

Mechanical Systems for Buildings Maximize Thermal Comfort – Reduce Energy Use

Architectural Acoustics Acoustical Comfort

Water & Waste Systems Reduce Natural Resource Use

Course Subjects and Objectives

ARCH 3200 Technology 03

3

Week

Topics Readings (MEEB) Workshop /Quiz

1 F 9/7 2

W 9/12 Architectural Acoustics: Measuring Sound 22.1-22.7 TH Quiz Due

F 9/14 Sound Absorption, Room Acoustics 23.1-23.18 3

W 9/19 Sound Isolation and Noise Control Workshop

F 9/21 Auditorium Acoustics 24.1-24.36 Quiz 4 W 9/26 Water and Waste Systems 18.1-18.8 TH Quiz Due

F 9/28 5

W 10/3 Water Sources and Municipal Waste 19.1-19.12 Workshop

F 10/5 6

W 10/10 Water and Waste Systems in Buildings 20.1-20.11

F 10/12

Quiz 7

W 10/17 Introduction to Mechanical Systems 12.1-12.14 TH Quiz Due

F 10/19 for Large Buildings 8

W 10/24 Architectural Form and HVAC Systems 12.15-12.21 Workshop

F 10/26

Quiz 9

W 10/31 Architectural Lighting: 13.1-13.28 TH Quiz Due F 11/2 Vision, Color and Perception 10

W 11/7 Characteristics of Electric Lights 14.1-14.20 Workshop

F 11/9 Bulbs, Lamps and Luminaires, Electric 11

W 11/14 Lighting Design: Prediction Techniques 15.1-15.17 Workshop

F 11/16

12

W 11/21 Lighting Design Strategies and Controls 16.1- 16.32

F 11/23

13

W 11/28 Daylighting Design: Prediction Techniques 17.1-17.30

F 11/30 Case Studies of Integrated Systems 13

W 12/5 Quiz Finals

ARCHITECTURAL ACOUSTICS

1. Basics of Sound and Hearing

• Sound and Perception

• Measurement of Sound

2. Noise: Sounds we don’t want to hear

• Sound Isolation

• Sound Absorption and Noise Criteria

3. Music and Vocals: Sounds we do want to hear

• Room Acoustics

• Performance and Concert Halls

1. SOUND AND VIBRATION

Is sound a particle or a wave?

Sound is a vibration in an elastic medium such as air, water, most building materials and the earth.

Pressure is a force per unit area.

Sound energy progresses rapidly, producing extremely small changes in atmospheric pressure and can travel great distances.

However, each vibrating particle moves only an infinitesimal amount to either side of its normal position.

Pure Tones

A pure tone is a vibration produced at a single frequency.

Complex Sounds

Tp = 1 / f

Tp = period (sec/cycle)

f = frequency (cycles/sec) or Hz (Hertz)

2. WAVELENGTH

l = 1130 / f

l = wavelength (ft)

f = frequency (hz)

3. VELOCITY OF SOUND

Sound travels at a velocity that depends primarily on the elasticity and density of the medium.

Air: 1130 ft/sec

Steel: 16,000 ft/sec

Concrete: 12,000 ft/sec

4. FREQUENCY OF SOUND

Octave bands are identified by their center frequencies. A doubling of the frequency is perceived as the same note or tone, one octave higher.

5. FREQUENCY RANGES OF AUDIBLE SOUNDS

Hearing range for a healthy young person:

20 to 20,000 Hz

Human speech contains energy from about:

125 to 8000 Hz

6. SENSITIVITY OF HUMAN HEARING

7. SOUND INTENSITY AND THE INVERSE SQUARE LAW

I = W/4pd2

I = sound intensity (W/m2) W = sound power (W) d = distance from sound source (m)

I1 / I2= (d2 / d1)2

I = sound intensity (W/m2) d = distance from sound source (ft or m)

L1 = 10 log (I / IO)

L1 = sound intensity level (dB) I = sound intensity IO = reference sound intensity,

10-12 (W/m2)

8. DECIBEL SCALE

Change in

Sound Level (dB)

1

3

6

10

20

Change in

Apparent Loudness

Imperceptible (except for tones)

Just barely perceptible

Clearly noticeable

About twice (or half) as loud

About 4 times (or one-fourth) as loud

CHANGES IN SOUND LEVEL

Common Sounds in Decibels

The purpose of the phon scale is to compensate for the effect of frequency on the perceived loudness of tones. By definition, 1 phon is equal to 1 dBSPL at a frequency of 1 kHz

Doubling the distance:

• 6 dB for point sources

• 3 dB for line sources

9. NOISE REDUCTION WITH DISTANCE

Doubling the Distance

From 10 to 80 feet away is three doubling of distance

Three doublings x 6dB / doubling = 18 dB reduction

When Two dB

Values Differ by

0 or 1

2 or 3

4 to 8

9 or more

Add the Following dB

To the Higher Value

3

2

1

0

DECIBEL ADDITION

SOUND LEVEL METERS

PERCEPTION AND LOUDNESS

SOUND LEVEL METERS

Weighting Scales

dBA Closest to human hearing Corresponds to an inverted 40- phon contour and discriminates against low frequencies as does the human ear.

dBC Nearly “flat” Corresponds to an inverted

100-phon contour and does not discriminate against low frequencies. Use this weighting scale to investigate the content of lower frequencies in a sound spectra.

SOUND SPECTRA FOR COMMON SOUNDS