Building Elements React To Moisture As Artful Inspiration

Chao Chen from the Royal College of Art made a project on building materials that react to external conditions without human interference. Chen was inspired by a pinecone and how it naturally opens and closes from wet weather. Pinecones are made up of two layers, one that is more porous than the other—when the outer layer gets wet it expands more than the other layer causing it to scale.

Chen attempted to replicate this action by creating a tile where the outer layer curves the material away when wet. This reactive material could offer a way for architects and engineers to incorporate a customizable construction that alters the way people interact with their built environment. Chen suggests that this material may be used in structures that shelter you from the rain but when the sun comes out the tiles carefully curl up, allowing more sunlight in. If the material comes durable enough one day it could be used for bus shelters or even larger buildings in warmer areas.

Thermal and Moisture: Keeping the Weather Out

This course is based on the 2017 Florida Building codes and is approved by the AIA for a 1-hour credit. This course will focus on the “best practice” procedures to carefully plan and install thermal and weather resistant components.

The objectives of this course include:

  • Summarize the key elements (either natural or mechanical) of a properly ventilated structure.
  • List and describe at least 3 specific installation techniques and/or materials that contribute to a properly constructed roof system.
  • Outline at least one design strategy based on “best practices” for the construction of buildings in areas with high humidity.
  • Identify and implement proven methods that will effectively divert moisture from the foundation of a structure.

Here is a course excerpt on moisture protection for windows and doors:

Improperly flashed window and door openings are one of the most common mistakes made by contractors. This causes moisture to get into the wall, causing mold, mildew, and eventually, rot. A major reason for the mistakes made while installing windows and doors is that not every situation is the same.

Such as:

  • Is the house wrap installed yet?
  • Does the unit recess into the wall?
  • Does the unit install with a flange?

Proper window and door installation preserve the integrity of the building envelope.  Window and door rough opening sides should have the house wrap folded around and into the opening. The side flanges or brick molding will counter flash the sides of the opening and can be sealed with caulking or butyl tape. The top edge of the house wrap should be cut even with the rough opening and temporarily pinned or held up and out of the way of the window or door top flange.  If the window or door has an integral or well sealed top flange, it can serve as the window or door head flashing!

Windows with molded or integral top flanges don’t usually need additional head flashings. However, windows and doors NEED HEAD FLASHING!!! A metal or vinyl flashing (z-metal) installed on the top edge of the unit serves to positively divert any water to the exterior of the unit. The loose layer of house wrap can then be spot tacked with tape or fasteners over the head flashing. Remember:  Before installing the trims around the window or door apply enough caulk at the ends of the z-metal flashing to create a “dam”, which will keep water from running off the ends of the flashing and down the sides of the unit behind the side trims.

New Course: Danger in the Damp–Dealing with Mold

Architects Training Institute’s new course is called Danger in the Damp—Dealing with Mold. It will examine the design and construction methods of systems designed to withstand water penetration. It will start with an understanding of these systems and finding the source of intrusion then repairing and prevention.

This course teaches the following specific knowledge and skills:

  • Terminology used to discuss how entrapped water creates problems for building users
  • Measures to retard the infiltration of moisture into built environments
  • Where and why mold growth occurs
  • Testing and inspection to find water damage
  • Systems and procedures to inventory moisture damage following intrusion
  • Immediate and secondary actions steps to take following water intrusion
  • Indoor air quality issues and how to identify them
  • How to deal with mold growth, once it is discovered

Here is a course excerpt on the ways to reduce the chance of water intrusion:

 

There are straightforward steps that can be taken to reduce the chance of water intrusion. Specifying and using building materials that neither accept nor hold moisture is one practical solution. For example, rigid insulation will not hold moisture, whereas cellulose insulation will absorb the same. Metal siding will repel water, but wood siding becomes saturated unless protected. Single ply membrane roofing offers no lapped joints wherein moisture can reside, but that is not true of asphalt shingle roofing. Sandwich panels containing insulation faced with steel or aluminum sheeting are another prime example of materials which by their nature, repel moisture.

Construction detailing using forethought before construction begins can deny water entry. It is primarily based on a good imagination and an understanding of water behavior. Since precipitation tends to flow downhill, flashings below copings, below windows, above door and window openings and above breaks in the continuity of the building envelope where water should lap down over the next shield in the water barrier, will keep water from entering. If wind striking a building face has the potential to drive water up under flashing, then caulking should be specified, or other barriers put in place to prevent that. Capillary breaks can prevent water from bridging gaps. If there is a cavity into which moisture can enter and collect, weep holes should be provided to let that collected water drain from that cavity, back to the exterior. The devil is in the details, but unwanted moisture intrusion can be in the lack of them.

The above-mentioned material specification and detailing decisions should be choices made during the design process. The idea is to create a continuous envelope of materials that repel water and will not allow moisture to get through them and into the interior.

Another useful tool is ongoing efforts to find and eliminate any newly created gaps in the envelope through which moisture can get inside. Inspection during construction is the best time to do this, but it is also part of ongoing maintenance efforts. Indoor sources of moisture (other than the breath of inhabitants) can be found and fixed or eliminated. Uncontrolled air movement that pulls humid air in from the exterior can be controlled with airlocks or other known design devices.