cantilever decks waterleaks?

Question

Anyone have problems with new homes with a cantilever deck and waterleaks?

Answer 1

There are at least two likely scenarios for a cantilevered deck. One, typically found on Condos, is part of a post-tension slab that steps down about four inches and extends out from the exterior wall forming a balcony. The reason I don't think this is you, is you didn't say condo, and they typically are professionally waterproofed at exterior joints with a "bond breaker", and shouldn't be leaking at this point.

Two: joists protruding from the exterior wall, either from a masonry or frame exterior that support a flat deck of some sort.
Because the support joist extends back into the structure for support, it is referred to as "cantilever" :

http://en.wikipedia.org/wiki/Cantilever

I've been involved in custom home building since 1978, and I can tell you that this is all-too-often a nightmare scenario. One of the biggest problems is finding a satisfactory deck material that is asthetically pleasing, leakproof, and will move at the same rate as the home without cracking, warping, peeling, leaking, etc.

Your problem most likely is occuring at the point that your deck meets the exterior wall. You must completely remove any surface material and get to the structural deck material and flashing. Likewise, you need to examine the pan that the exterior doors sit in for leaks.

When I address problems like these, I make sure that the deck is nicely sloped and completely unobstructed, and finished with a material that is water-tight and durable (www.sanitred.com). The joint between the deck and outside wall has a fat bead of urethane caulk, completely visable for quick inspection. If neccesary, I remove and replace the bogus pan under the door with heavy-guage aluminum and joints that are riveted and sealed inside and out with urethane caulk. The railing and ballustrade is fastened to the deck in a manner that I never have to worry about water being obsstructed or leaking through my fasteners or support posts.

I wish I could count the number of times I have removed fractured concrete, warped and rotted deck boards, improperly installed flashing, improperly pitched decks, bogus finishes like Elastomeric or Drylok, bogus sealing materials like latex caulk and plastic roof cement, rusted or improperly made door pans,
corroded fasteners and flashing made of galvanized steel, (the list goes on)

I guess I am trying to paint a picture that this is serious business, and can cause extensive damage if left unresolved. I hope this information proves to be of some value.

Answer 2

need more info.....the leak would be where the deck attached to the house......flashing? .....deck pitched back toward the house?..many things..plz update!

Answer 3

see it that it is sloping towards the drain. if checked, paint it with elastomeric paint (or equivalent) to resolve the problem.