Condo Media - March 2013 - (Page 14)

by Jack Carr, P.E., RS, LEED-AP C A I R e g i o n a l N e w s MAINE Let’s Caulk Understanding Materials and Standards P erhaps by now the March wind-driven weather has convinced the board it has water infiltration problems, not to mention air infiltration issues. Interior gypsum board ceilings and walls are starting to stain, floors are beginning to get wet and warp and unit owners are complaining of mold formation. Often the answer is not façade re-siding or a new roof surface, but rather a need for new caulk. The best waterproofing materials in any building do not depend on adhesive properties. These materials are impermeable, they are shingled or overlaid and they depend on gravity and drip edges. But adhesion does have a place in creating a weather-resistant building envelope. Properly selected quality caulks and sealants are needed in key locations such as around doors and windows, roof penetrations, the boundary between dissimilar materials, siding corner joints, etc. The problem is caulks and sealants tend to have useful lives significantly shorter than the materials they are applied to and there are too many caulks and sealants to choose. So let’s talk about caulk. Let’s take the mystery out of which type of caulk to use for each of the many applications found in any building. Certainly the board or building committee can depend on their engineer or architect or contractor to provide good advice on caulk selection or methods of installation, but having a basic un14 Condo Media • March 2013 derstanding of caulking will give the process a better chance for success. Options and Applications The first questions to resolve about each caulking project are its longevity needs, flexibility of the joint, cure time available and ease of clean up. These issues are further complicated by the many different types of construction materials used today, likely weather conditions, whether this is a new caulking application or a re-caulking application and the future application of paint. Therefore, let us first consider the properties of the typical caulks selected in condo projects: Acrylic latex: This is sometimes referred to as “elastomeric caulk” and is the most widely used and easiest caulk to apply for both interior and exterior projects. It has more elasticity than straight latex caulk, which is more suitable for interior work. Both can be painted but are not as flexible in wide temperature ranges as the high-performance caulks and they must be applied in ambient temperatures of more than 40 degrees Fahrenheit. They should never fill spaces greater than one quarter of an inch and have a useful life of 10 years. These caulks are easy to clean up as they are water based. Butyl: This rubber-based caulk has been available for a long time and is still very affordable. Its stringy nature does not make it suitable for a clean, finished appearance, but it has good adhesion characteristics and is very water resistant, making it a good applicant for roof component repairs, walkways and exterior joints with lives of up to 10 years. Butyl should not come in contact with modified bitumen flashing tapes or rubber roof membranes.

Table of Contents for the Digital Edition of Condo Media - March 2013

Condo Media - March 2013
From the CED’s Desk
Editorial Board
CAI News
CAI Regional News
Asked & Answered
Homeowner’s Corner
Vendor Spotlight
Industry Perspective
Self-Managed Association Boards
2013 CAI-NE Spring/Summer Service Directory
Classified Service Directory
Advertisers Index

Condo Media - March 2013