Skip to main content

Water transport in cavity assemblies

What two products or means address the mechanisms that transport water through a wall or roof cavity?

AnswerVapor barriers seek to limit water vapor diffusion through a wall or roof assembly, whereas air barriers address air leakage by stopping infiltration and exfiltration. However, air leakage is capable of transporting more moisture through the assembly than water vapor diffusion.

Comments

Try These Too!

Parking units

What are the car stall dimensions for a compact car? Answer A compact car stall size can be set by each municipality and therefore varies. Generally it is 7ft 6in wide by 15ft 0in long. However, in Fresno CA it's 8 1/2ft x 16ft and according to an Iowa urban design manual, it's 7ft 6in by 16ft. ARE 4.0 exam prep: SPD

Townships double post!

How many sections are contained within a township? Answer 36 (each is 1 mile square) What are the dimensions of 1/2 of a township? H & W Answer 18 miles square (3x6 sections) ARE 4.0 exam prep: SPD

Radius of gyration

For column design, the radius of gyration incorporates area and the moment of inertia. This value represents the resistance of a cross-section to buckling, which in columns happens under a load parallel to its lesser dimension. The slenderness ratio is the ratio of a column's effective length (modified by K-value to account for its end conditions) to its least radius of gyration. For a W12x16 A36 steel column with a least radius of gyration of 0.773, whose ends are both free to rotate but fixed in translation (K=1), what is it's slenderness ratio? Answer Kl/r = (1)(12feet)(12in/ft) / 0.773 = 186.3 ARE 4.0 exam prep: SS