SIll plate waterproofing

[coregis]

I'm having part of our back porch enclosed off the existing exterior to create a very small mudroom/shoe closet/lean-to. Seems similar enough to garage construction on concrete slab so hopefully this is not out of line.

I decided to hire it out since I never did any framing or door hanging, but now I'm a bit worried about the waterproofing plan. We are in the Pacific Northwet so water is my main concern.

The PT sill plates sit on a raised 5" concrete slab stoop and are flush on 2 of the 3 new sides.



There will be a new exterior door that sits against some flat concrete. I am more worried about this wall due to water sitting on the flat section and possibly wicking in. There is a overhang above all this, but as you can see in the photos like everything in this neck of the woods it gets wet regardless.



You can see the slabs get pretty wet from rain, even the sides. The contractor has started putting siding on one of the sides and said he was going to caulk between the siding and the slab. I was thinking sealing the sill first would not be a terrible idea. Or maybe I should just keep my mouth shut.

I'm thinking of some sort of liquid flashing product or caulk at the sill plate/slab interface would help, but would like to hear any ideas. Also considering cutting channels into the concrete. Thanks.

 

[jack stand]

What's going on with the roof?
Is it going to dump water on the side that's not raised?
An overall picture would be helpful.

 

[Zeke]

Anything I would suggest is too late now. Caulk the plate.

 

[mike93lx]

Liquid flashing. Prosoco is the first that comes to mind

 

[Bert_]

You are going to fight water forever with that design. With no break in the slab water will wick right under that wall.

Caulk, sillseal, whatever you want to use is going to be a temporary fix for a permanent problem

 

[PoorUB]

Should have been a small step at the sill, even a couple inches would be better than level.

 

[usmc_noma]

I would think there would be some sort of flashing down in addition to what the previous post mentioned. You will continue to have issues. I am fighting this with an exterior door to my garage. I need to replace the sill plate, door frame, and exterior molding. The plan is pvc molding, metal flashing, new sill, and a door frame where the lower portions are made of pvc. I think it's pvc, but whatever it is is not wood.

 

[coregis]

Thanks all, really helpful and telling me how it is. Here's the overall look- also added to first post. We are basically adding a coat closet and adding a second exterior door- not touching the current exterior.

There is an overhang, and it is all raised. I think the sides are 'good enough' but the front sill junction really worries me. We are in constant mist for 9 months- that curvy part is always wet, but never puddles.

On the other hand, we are bolting a 25 sf shed onto my house here, and the level section of concrete by the front door is not that big (we may have to extend it depending on how comfortable the step and door transition is...).

Should I be the guy demanding we follow youtube videos of the crews who are designing homes with the goal of being able to suffocate everyone inside while staying bone dry under 50 feet of water? I'm going to have dricore inside for a reason...




But here's the video I think may have a fighting chance here-

They basically make a kerf cut parallel to the wall and run flashing into it (with plenty of caulk).


I am probably going to pick up some Prosoco Joint and Seal filler and so the outside of all the sills this weekend. (or would the liguid flash be better- the youtube dude recommends the joint and seam one for whatever reason...)

I think in general I need to have a heart to heart with the guy- after it rotting enough to get the door stuck in 6 months, my biggest fear is moving the shoes out of the kitchen into a refrigerator, and it seems like the weatherproofing plan is going to be putting a ton of caulk everywhere. It is a neighbor, so that complicates things- plus my wife wants it done yesterday and for $100 so he may just be trying to make her happy. The house is ancient and poorly built and has survived well enough so not sure I need to have the taj majal of coat closets either.

 

[rayra]

Totally garbage build, sorry. Putting that trim right on the slab is just going to wick water like crazy. You'll have mol din the wall in no time and the the whole wall rotten in a year.

Should have done some sort of concrete curb / stem wall, with a moisture barrier between it and the sill plate, THEN the wall enclosing the space. What is show in that picture looks like absolute garbage.


eta 3rd post in a 7yr-old account.
I'm really starting to think these 'new' accounts with ridiculous or intractable problems are just created to stir the pot / get attention.

 

[karoc]

Not speaking for experience but echoing what Alliance suggested, maybe go up the wall about 12" and if possible gutters installed. Liquid flash then maybe sheet metal flashing, but that will only help with lasting little longer. Sometimes it just can't be perfect like we want it to be so have try to make it the best it can be.

 

[mike93lx]

eta 3rd post in a 7yr-old account.
I'm really starting to think these 'new' accounts with ridiculous or intractable problems are just created to stir the pot / get attention.

Many of them are spammer, but some people don't live on forums. Not sure why but it happens