Concrete In The Cold
There’s been plenty of freezing rain over the last few days and for some reason, I thought it would be a bright idea to climb up on the roof to take the photo above. I saw the truck (and more importantly, the stark contrast between it and the operator’s orange jacket) and thought to myself “So what if you can’t feel you hands, you’ll still be able to climb that ladder. Get up there and take that photo.” So up I went, camera in hand.
It was a little snowy and icy up there, but all in all not too bad. For the most part the roofing is complete, however there are still a few things that need to be completed. The sides of the clerestory are going to be wrapped in Vapor Shield (thanks to everyone who suggested it) to further protect it and the windows need to be installed (which will hopefully happen next week), but everything else is pretty much done. While I was up there, I figured I might as well snap a few shots of the drains with their strainers installed so you can get a better sense of how they’ll look/work. Pretty exciting stuff, I know.
You’ll also notice the 2 built-up boxes on the roof—these are for the sun tunnels we’ll have in the en-suite bathroom and walk-in (walk-through?) closet. We decided to use Velux Low Profile sun tunnels, both of which should paint their respective rooms with plenty of natural light. The instructions state that they’re intended for pitched roofs only (between 15° and 60°), but we contacted the manufacturer and they said we’d be fine if we simply raised them up and away from possible snow buildup. I don’t know the exact measurement, but I think they stand somewhere around 12” off the roof.
After exhausting my photographic options on the roof, I made my way back down to safety and proceeded into the basement. Well, not actually into the basement, but I did uncover the opening for the stairway so I could lean in and take some shots. That’s close enough, right? Of course, none of them turned out because it was kinda’ dark down there, so you’ll have to take my word that the next few paragraphs are legit. Picture this…
I hadn’t originally intended on putting insulation under the slab, but after a few persuasive arguments (thanks Scott!) I was convinced otherwise. Once the drains were run, we tamped the gravel down and covered everything with vapor barrier. All of the seams were tuck taped and then 1” of rigid foam insulation was laid. 2” would have been ideal, but I just couldn’t justify the added costs. Hell, I really couldn’t justify the cost of 1”, but what are you gonna’ to do? We’ll at least see some gains from the thermal break between the slab and the ground, which is better than nothing I suppose. Regardless, all of those seams were Tuck Taped as well and everything was covered up with concrete.
Now, concrete doesn’t like the cold particularly much, so we needed to block all of the openings and run a heater down there. Of course, this just made everything foggy, but at least it looked warm and toasty. I’m not too sure how long the heater will be running down there, but it’s currently sitting on a temporary shelf that’s suspended from the ceiling. I suppose you would typically rent these things, but apparently it only cost a little more to purchase it outright and I’m now the proud owner of a 70,000 BTU/Hr. Kerosene Forced Air Heater with built-in thermostat. I guess I’ll sell it on Craigslist when we’re done (or maybe I can convince Steve that he needs a snazzy heater for his next project?!)
Post Tags: basement, cold, concrete, roof, waterproofing
I hope that they remembered to create a thermal break between the foundation walls and the basement slab with rigid foam insulation.
— posted on December 12, 2008The foundation is ICF, so the foam went all the way down to the footings. Gravel was tamped down and made flush with the top of the footing, after which vapor barrier and rigid foam was placed on top. I’m pretty sure everything will be nice and insulated (and even if it’s not, there’s no going back now!)
— posted on December 12, 2008Oh yeah, forgot about your ICF’s. Looks like they did it right then. You’ll have a nice warm basement.
I wasn’t going to post this. However, I took another walk by your place the other day. I noticed that your builder was quite sloppy with the sill flashing on the first floor front big windows. It’s ripped, torn, doesn’t actually extend all the way across the top of the sill opening, etc. There also other areas where the housewrap and sill material wasn’t installed properly and it will be impossible to fix now. Also on the windows, it looks like there might be some type of flashing (beige in colour) but I am not sure what it is or is it actually part of the window frame. (What is it?) If it is flashing, does it extend from the outside to the inside so that you can tuck tape the housewrap to it on the outside and the vapour barrier to it on the inside? (If not there’s nothing you can do now). In any event, the corners don’t seem to be done properly at all as they is no flashing at those points on the outside at the 90 degree corners. An additional piece of flashing should have been placed on thise corners so the flashing is continuous across the outside plane. People variously use Blueskin, housewrap, ice & water shield and other custom materials to do this. I favour Blueskin myself and it’s only a few hundred dollars to flash an entire house for materials.
I know I’ve harped on this before, but it’s really sad that you are probably paying well over a half-million dollars (probably $750K or more I bet) to build your dream home which you plan to live in for a while, have invested all this time and effort in research and monitoring your builder, yet no one is making sure that you have a good tie-in of the vapour barrier to the openings on the inside, well-waterproofed window and door openings and a good tie-in of the typar with the openings on the outside.
You can spend all the money you want on energy efficiency and green products but almost 1/2 of your energy savings will come from the proper sealing of the vapour barrier on the inside at wall protrusions, window/door openings, electrical boxes and the like. The other 1/2 will come from the amount of and proper installation of the insulation. Proper windor and door opening waterproofing and housewrap tie-in is what is going to avoid water infiltration and mold. Because, eventually, all wall fascia will allow water in whether they are brick, stone, wood siding or whatever (and whether the windows are caulked and spray foamed or not – this is why the CMHC and CSA, etc. put out publications on how to flash windows properly). You just don’t want that water to be able to enter your structure after it gets past the wall or into the window/door opening and that’s what proper housewrap and flashing and sealing techniques are all about. I can’t stress these points enough.
Ok, I’ve said it. Good luck.
— posted on December 12, 2008