Jump to content

Seal gaps at window / trim joint?


inspectorwill
 Share

Recommended Posts

The pictured installation is typical for my area. This is a traditional stucco home with wood trim installed around vinyl clad windows. The window / trim joints are commonly caulked. However, the caulking typically deteriorates within a couple years. Recaulking on a regular basis, especially at 2nd floor windows, does not seem practical. In the close up pic, you can see the lathe in the gap between the window frame and wood trim. I have two questions. 1- Is the caulking really necessary? 2 - Is there a better installation method with this type of siding and trim? Gaps will inevitably occur between the window frame and wood trim and continual caulking is not practical.

Click to Enlarge
tn_2009111904921_P1010014.jpg

52.93 KB

Click to Enlarge
tn_2009111904948_P1010036.jpg

41.49 KB

Click to Enlarge
tn_2009111905019_P1010037.jpg

21.68 KB

Link to comment
Share on other sites

The pictured installation is typical for my area. This is a traditional stucco home with wood trim installed around vinyl clad windows. The window / trim joints are commonly caulked. However, the caulking typically deteriorates within a couple years. Recaulking on a regular basis, especially at 2nd floor windows, does not seem practical. In the close up pic, you can see the lathe in the gap between the window frame and wood trim. I have two questions. 1- Is the caulking really necessary? 2 - Is there a better installation method with this type of siding and trim? Gaps will inevitably occur between the window frame and wood trim and continual caulking is not practical.

I'd expect that a structural sealant joint, with backer rod and good-quality sealant would last at least 5 or maybe even 10 years. But it's got to be applied properly.

- Jim Katen, Oregon

Link to comment
Share on other sites

Hi,

The stucco is going to move and vinyl windows will expand at twice the rate of aluminum wood or fiberglass, so keeping the joint sealed is a challenge with the trim flush to the face of the stucco.

Jim's solution will probably work, if it's used on both sides of the trim, but the stucco guide shows another solution. The window is flashed with flexible bituthene flashings over the nailing fin at the sides and top and under the fin at the bottom; the stucco ending in a treated wood nailer/plaster stop butted right up to the sides of the window casing at the sides; a 1/4-inch gap between the casing and the stucco at the bottom; a 3/8-inch gap between the stucco and the casing at the top; and then the trim is applied over the plaster stop. A metal head flashing laps them both at the top, and then the gap at the bottom is filled with backer rod and tooled with sealant.

Click to Enlarge
tn_200911194719_NailOnWindowFlashingAndTrimDetails1.jpg

53.23 KB

Click to Enlarge
tn_20091119481_NailOnWindowFlashingAndTrimDetails2.jpg

57.77 KB

Link to comment
Share on other sites

Terpolymer or polyurethane will out last butyl by several years.

Tom

All joints on stucco walls need periodic inspections and maintenance. It's not a question of outlasting, it's a question of staying flexible so it can handle the differences in range of movement of the vinyl, trim and stucco; that means that one must use backer rod or the caulk will be defeated by the movement regardless of what it is.

ONE TEAM - ONE FIGHT!!!

Mike

Link to comment
Share on other sites

  • 1 year later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...