PDC Natural Building & Shelter Design 2

Question 1

Adobe construction is distinguished from cob primarily by which characteristic?

Accepted Answer

Using pre-formed, sun-dried earthen bricks laid in courses

Answer

Adobe uses pre-formed, sun-dried mud bricks laid in courses with earthen mortar, distinguishing it from monolithic methods like cob where the wall is built as a single mass.

Question 2

What is the primary structural advantage of rammed earth construction over other earthen building techniques?

Accepted Answer

It creates dense, load-bearing walls with high compressive strength

Answer

Rammed earth compresses moist soil in formwork layer by layer, creating extremely dense walls with high compressive strength well-suited for load-bearing applications.

Question 3

How do Compressed Earth Blocks (CEB) primarily differ from traditional sun-dried adobe bricks?

Accepted Answer

They are mechanically pressed to achieve higher density and uniformity

Answer

CEB are formed using a mechanical press that compresses moistened earth under high pressure, producing a more uniform, denser block than hand-formed and sun-dried adobe.

Question 4

A thermal chimney (solar chimney) in a natural building functions by using which physical principle?

Accepted Answer

Using heated air's natural tendency to rise, drawing cooler replacement air in at lower openings

Answer

A solar chimney works through the stack effect — the sun heats air inside the chimney, causing it to rise and exit at the top, drawing cooler outdoor air into the building from lower openings.

Question 5

In natural building, a 'rain screen' wall assembly primarily protects against what problem?

Accepted Answer

Water infiltration by creating a drainage and drying cavity behind the outer cladding

Answer

A rain screen creates a ventilated cavity between the exterior cladding and the wall assembly, allowing any water that penetrates the outer layer to drain away and dry before reaching the structural wall.

(PDC) Permaculture Design Certification Practice Test

(PDC) Permaculture Design Certification Practice Test

PDC Natural Building & Shelter Design 2