Questions about weather sealing

[DaveHI]

I had real problems with h20 soaking my underfloor insulation before I got my enclosure built. Had to start the drying cycle over twice.

I ended up using hydraulic cement (20 lb bucket from Home Depot) to seal the cracks around the entry area and to cover the edges where the insulation board was exposed. Also smushed it into the seams in the durock enclosure since I had left over. The stuff is supposed to be good for sealing leaks through basement walls, I figured it would do the trick on keeping water out.

I then used that pink/red waterproofing membrane over the whole thing to make sure it shed water. (also Home Depot which is about the only place we have for that sort of thing). I doubted stucco would stick to the membrane so I've skim coated the enclosure with tile thin set. If it even stops raining I'll stucco over that.

So far my hearth seems dry but I probably should go put some plywood over the entire entry area. We have horizontal rain today (30 MPH winds and showers). Haven't been able to use the over due to time/weather for about 3 weeks so not sure how successful any of this has been. Last time I peeked inside everything still seemed bone dry.

[Ken524]

Dave,

Thanks for the info!

Ken

[Dino_Pizza]

Hi Ken, I know you're looking for a solution making it water-tight at the front edge of the vent landing but since I'm going to build my WFO on FB board (just like you did with super isol) I want to address it earlier. What is your (or anyones) opionion on cutting the insulating board 1" short of the front edge, leaving your firebrick landing overhanging 1" over it and filling that 1" deep by the width of the landing with Heatstop or Refrax and then doing whatever granite-tile etc right up to it? Is this a good solution, I'm not proficient at this stuff so it may not solve the issue.
Thanks, Dino

[jet]

I was thinking that it might be good to pour a "raised hearth" section under the insulation with the idea being that if water seeped in on the hearth, it wouldn't come into contact with the insulation. I tried to capture the idea in the attached diagram.

[Dino_Pizza]

That makes sense Jet. I was trying to avoid doing any other concrete pour after the hearth slab but I seem to recall seeing another picture/post here where someone did just as you've shown on your pic. But I think it was a vermiculite/conc. mix and it following the contours of the oven floor & landing. More to ponder...

[jet]

I think that Dave (asudavew) did the contoured vermiculite/concrete mix under his oven.

[thebadger]

Ken,

I actually used the Sani Tred product to seal some cracks in my basement. very interesting stuff. Sort of like "liquid" rubber. I think this might be an option. It's not cheap but you wont' need much. They sell a "sample" batch which may be enough for your needs. After you "paint" it on you could just pour the concrete. Only issue to think about is would the wet concrete adhere to the sani tred.

IM me if you want more infor.

Good luck,
thebadger

[Ken524]

Originally Posted by Dino_Pizza

Hi Ken, I know you're looking for a solution making it water-tight at the front edge of the vent landing but since I'm going to build my WFO on FB board (just like you did with super isol) I want to address it earlier.

Dino,

Actually, I didn't use the SuperIsol/FB board. If I had, this would be a non-issue .

Ken
(President of the "Stay away from Kaowool Board" club)

[Ken524]

Originally Posted by Dino_Pizza

cutting the insulating board 1" short of the front edge, leaving your firebrick landing overhanging 1" over it and filling that 1" deep by the width of the landing with Heatstop or Refrax and then doing whatever granite-tile etc right up to it?

That's actually one of my options. I think it's a good idea.