Where Roof Deck Sealant Fails

It's easy to look at one's balcony or roof deck and feel confident that the surface integrity is good and that the existing sealant is keeping any moisture intrusion from occurring. However, these sealant failings often happen in places where homeowners down expect and can cause costly, lasting damage if not repaired. Below, we take a look at three parts of your roof deck where sealant failures are common.

(If the deck is not resealed or color coated at least every 3 years, then moisture can enter the top coat and the underlying wire lath will begin to rust and fail.)

The Door Threshold

The edge of your roof deck that terminates at door threshold of the house is notorious for sealant peeling and failure. This is due to heavy foot traffic that that area receives, but also because it's at a critical pressure point in the construction of many houses. As buildings settle and move over time, the connection between your house floor and your roof deck floor can be stressed, shift, and damage the sealant.

The Drain

Your roof deck drain is critical to removing excess water from the roof deck surface. However, this part of your roof deck, over time, can be susceptible to sealant damage. This is often due to rust, which can cause bubbles/bloat around the drain's rim and affect how the drain itself sits in its port. These conditions can damage sealant and create exposure around the perimeter of your drain.

(The sealant at drain connections must be maintained regularly. If the sealant fails here, then the coating will separate and allow intrusion around the drain assembly or the coating can lose bond.)

The Railings

If your balcony or roof deck has a metal railing of any kind, the points at which they meet the deck's surface could become vulnerable to moisture intrusion. This points experience a battery of vibrations from use and, more critically, can experience rust over time that can result in sealant damage.

(Wood rail posts tend to shrink and move over time. If the sealant at the post connection fails, it will allow moisture intrusion into the framing below.)