Mistakes so far

What is the transmission loss formula?

TL = 10 log₁₀(1/τ), in dB.

What is TL when τ = 0.01?

20 dB; only 1% of incident energy is transmitted.

What four features improve floor sound insulation?

Mass, resilient layers, cavity absorption, decoupling.

Why use an independently supported ceiling?

To reduce vibration transfer through rigid connections.

Which absorber is best for high-frequency noise?

Porous materials, such as glass wool.

Which absorber is useful for low-frequency noise?

Membrane absorbers or suitably tuned resonators.

What is the formula for echo distance?

d = vt/2; the sound makes a round trip.

What happens when point-source distance doubles?

Sound pressure level drops by about 6 dB in a free field.

What is the difference between absorption and insulation?

Absorption controls reflections; insulation limits transmission.

How does a noise barrier reduce sound?

It blocks direct sound; some sound still diffracts around it.

What is the aim of loudspeaker positioning?

Even coverage, strong direct sound, minimal delayed reflections.

Why can resonance reduce sound insulation?

It increases vibration and transmission near resonant frequencies.

What is climate mitigation?

Reducing greenhouse gas emissions or increasing their removal.

What is climate adaptation?

Adjusting buildings to withstand climate impacts.

Name six factors influencing thermal comfort.

Air temp, radiant temp, humidity, air speed, clothing, activity.

What creates positive pressure on a building?

Wind striking the windward face.

What commonly occurs on a building's leeward side?

Lower pressure or suction, often with turbulent wake flow.

What is the urban canyon wind effect?

Wind can accelerate through narrow gaps between buildings.

How can trees cool an outdoor space?

Shade and evapotranspiration.

What is the purpose of external solar shading?

Reduce unwanted solar gains and summer overheating.

Why is thermal mass useful?

It stores and releases heat, moderating temperature swings.

What does a low surface-to-volume ratio indicate?

Less exposed envelope area per unit of heated volume.

What is the unit of wavelength?

Metres (m), not decibels.

What is the wavelength formula?

λ = v/f.

What is the unit of transmission loss?

Decibels (dB).

What is the unit of thermal resistance?

m²·K/W.

What is the unit of U-value?

W/(m²·K).

What is the unit of S/V ratio?

m⁻¹.

How do you calculate S/V ratio?

Exposed envelope area divided by heated volume.

What is the key solar-overhang calculation check?

Use the correct shaded height from the diagram; check units.