Architekwiki
  • WIKI
  • Start Here
  • Resources
  • Other
    • MyCorbu
    • Reading List
    • OFFPLAN
    • Details
    • About
    • Sign Up
    • Terms of Use
  • MyCorbu APP
  • WIKI
  • Start Here
  • Resources
  • Other
    • MyCorbu
    • Reading List
    • OFFPLAN
    • Details
    • About
    • Sign Up
    • Terms of Use
  • MyCorbu APP

Architekwiki

A Resource For Architects
Subscribe

RainScreens

12/27/2012

 
Picture

This is a quick overview of the RainScreen concept.

Concept
In a rainscreen design the exterior surface of the wall is not considered a weather barrier as in most traditional wall systems. Think of wood siding; nothing is intended to get past the siding. In a rainscreen wall, most water is kept out but not necessarily all water. Any water that makes it through the screen is conducted down through the air space and back to the exterior. The archetypal example is a masonry cavity wall. Rather than just one line of defense, the rainscreen provides two lines of defense and the critical second line of defense is subject to only a fraction of the rain water, and it is not wind-driven by the time it reaches the inner barrier.

Components
  • Structural backup. Studs or CMU. Metal studs are most popular but are less forgiving than concrete mansonry. In a metal stud the gage of the steel, the type of and material of the fasteners is crucial. Structural integrity comes down to the threads of the fastener not losing their bite in the flange of the stud (corrosion and electrolysis undermine everything - can you be sure the correct fasteners are used properly?)
  • Air and water barrier. This needs to be monolithic. Pay special attention to joints and penetrations.
  • Insulation. This also needs to be monolithic with sealed joints and penetrations, and a minimum of 'thermal shorts'.
  • Air space. In masonry, code requires 1" min and 5.5" maximum without specially engineered tie-backs. Equalizing the pressure through weather-resistant vents is desireable. This prevents a negative pressure developing in the air space that sucks moisture in. Encourage vertical ventilation of air space by providing barriers to horizontal movement.
  • Rainscreen. There are many types of rainscreen: brick veneer, 3-5/8" calcium silicate masonry units, 1-3/8" calcium silicate panels on a clip system, terra cotta, stone veneer, fabricated panels of many types.
PROs
  • Generally more forgiving weather barrier for the building
  • Better energy performance
  • Can be a 100 year solution
  • Can be lighter weight
CONs
  • Penetrations, doors and windows, are critical. Repairs much harder.
  • Concept doesn't have decades of history to show up any long-term weaknesses (during the past half century there have been plenty of new ideas that didn't pan out)
  • More expensive


CONCLUSION
A rainscreen wall is becoming the expected, modern solution to exterior walls. The benefits outweigh the disadvantages. Where budgets allow and capable workmen can be counted on to implement the design, the rainscreen is the best solution. Bear in mind that it will take more design effort to create a good rainscreen, and nothing can be readily delegated to the contractor, unless he is a specialty rainscreen contractor with proven experience (there are none in many areas). A good design will take more research, detailing, and follow-thru during construction than a barrier wall. Because of this attention to detail, not every project is a candidate for a rainscreen.

The diagrams below were taken from Wikipedia - http://en.wikipedia.org/wiki/Rainscreen_cladding

Picture
Rainscreen Cladding Principle
Picture
Air Circulating Scheme

Comments are closed.
    Resources

    Start Here

    Picture

    Picture

    MyCorbu

    Trello-PM

    FeeCalqs

    Picture

    Terms of Use
    Your use of Architekwiki is implicit agreement with the 
    ​
    Terms of Use.

    RSS Feed


    Categories

    All
    Business Development
    Communications
    Concepts
    Design
    Detail
    Estimating
    Finances
    Legal Issues
    Management
    Miscellaneous
    Money
    MyCorbu
    People
    Planning
    Process
    Projects
    Records
    Services
    Specifications
    Standards
    Time
    Tools


    Archives

    February 2021
    January 2021
    December 2020
    November 2020
    October 2020
    September 2020
    August 2020
    June 2020
    April 2020
    March 2020
    February 2020
    January 2020
    December 2019
    November 2019
    October 2019
    September 2019
    August 2019
    July 2019
    June 2019
    May 2019
    April 2019
    March 2019
    February 2019
    January 2019
    December 2018
    November 2018
    October 2018
    September 2018
    August 2018
    July 2018
    June 2018
    May 2018
    April 2018
    March 2018
    February 2018
    January 2018
    December 2017
    November 2017
    October 2017
    September 2017
    August 2017
    July 2017
    June 2017
    May 2017
    April 2017
    March 2017
    February 2017
    January 2017
    December 2016
    November 2016
    October 2016
    September 2016
    August 2016
    July 2016
    June 2016
    May 2016
    April 2016
    March 2016
    February 2016
    January 2016
    December 2015
    November 2015
    October 2015
    September 2015
    August 2015
    July 2015
    June 2015
    May 2015
    April 2015
    March 2015
    February 2015
    January 2015
    December 2014
    November 2014
    October 2014
    September 2014
    August 2014
    July 2014
    June 2014
    May 2014
    April 2014
    March 2014
    February 2014
    January 2014
    December 2013
    November 2013
    October 2013
    September 2013
    August 2013
    July 2013
    June 2013
    May 2013
    April 2013
    March 2013
    February 2013
    January 2013
    December 2012
    November 2012
    October 2012

    Resources
VISIT ARCHITEKWIKI'S RESOURCES
Picture
Architekwiki | Architect's Resource | Greater Cincinnati | (859) 444-4560
© 2012-2020   Architekwiki​