I have an attached garage in the basement (Built around 1950) with some kind of concrete roof that also serves as a patio. There is no roof or anything else on this patio, and the slope is just so-so. Some water can accumulate in a few spots on the patio.
Moisture has been detected on the underside of this patio, which presumably is because the waterproofing layer in the concrete slab has partially stopped functioning. I've also noticed that small bits of concrete can fall in some places in the garage, which I also guess is due to the moisture. This is obviously not good and something needs to be done, the question is just what. What I've been considering is roughly this:
1. Put a roof over the entire patio. However, that doesn't feel completely optimal because it's quite large and it would be nice to have some patio without a roof as well.
2. Break up the patio floor, remove the waterproofing layer, apply a new one, and cast again. This also doesn't feel quite right. Partly because I'm unsure about the structural integrity while I'm doing the job and partly because it seems like a lot of work.
3. Make sure the slab dries out properly (Heat from below + tarps maybe?) and then apply a new waterproofing layer and pour a bit more concrete on top. But how do you know if the slab can handle this extra (albeit evenly distributed) weight? Am I going to shoot myself in the foot and trap moisture in a bad way if I do this?
4. Like 3 but instead apply a waterproofing layer and cover with frost-resistant tiles. Feels like the simplest and perhaps the most attractive, but will it be good enough?
Other suggestions are also welcome, wise, insane, sensible, or just strange.
/Kaj Nyström
Moisture has been detected on the underside of this patio, which presumably is because the waterproofing layer in the concrete slab has partially stopped functioning. I've also noticed that small bits of concrete can fall in some places in the garage, which I also guess is due to the moisture. This is obviously not good and something needs to be done, the question is just what. What I've been considering is roughly this:
1. Put a roof over the entire patio. However, that doesn't feel completely optimal because it's quite large and it would be nice to have some patio without a roof as well.
2. Break up the patio floor, remove the waterproofing layer, apply a new one, and cast again. This also doesn't feel quite right. Partly because I'm unsure about the structural integrity while I'm doing the job and partly because it seems like a lot of work.
3. Make sure the slab dries out properly (Heat from below + tarps maybe?) and then apply a new waterproofing layer and pour a bit more concrete on top. But how do you know if the slab can handle this extra (albeit evenly distributed) weight? Am I going to shoot myself in the foot and trap moisture in a bad way if I do this?
4. Like 3 but instead apply a waterproofing layer and cover with frost-resistant tiles. Feels like the simplest and perhaps the most attractive, but will it be good enough?
Other suggestions are also welcome, wise, insane, sensible, or just strange.
/Kaj Nyström
I can actually see a rebar in one spot on the inside of the ceiling, incidentally in a corner where an old untreated downspout goes into the ground. Even though concrete is considered moisture-resistant, it doesn't seem to withstand being completely soaked indefinitely.
However, my amateur feeling is that if you manage to address the moisture problems from above, it should really just be a matter of waiting for it to dry out and then fixing the underside with some form of concrete filler, at least if, like me, you don't have major issues there. But it's the idea of adding waterproofing upon waterproofing that sets off small warning bells in the reptile brain for me.
However, my amateur feeling is that if you manage to address the moisture problems from above, it should really just be a matter of waiting for it to dry out and then fixing the underside with some form of concrete filler, at least if, like me, you don't have major issues there. But it's the idea of adding waterproofing upon waterproofing that sets off small warning bells in the reptile brain for me.
There are a few different systems for this problem. I have it myself, but in my case, the roof slopes the wrong way and forms a puddle.
I chipped away the old tiles that were in practically eaten-up concrete and filled the hole with thermal filler on top of the old hot asphalt. It adheres but not well.
Since I want to build a slope, I'm considering either styrofoam or foam glass. Unfortunately, the building height is limited due to patio doors. The problem becomes the thickness of the new surface layer. (I would like some insulation on the outside, which is why I don't want to cast slopes).
For waterproofing, asphalt or epdm rubber products are applicable. PVC does not mix with asphalt. There's a jungle here, but if you want to lay the layers yourself, it's probably Mataki Bituthene that applies. The others are welded or heated or poured onto the surface.
I chipped away the old tiles that were in practically eaten-up concrete and filled the hole with thermal filler on top of the old hot asphalt. It adheres but not well.
Since I want to build a slope, I'm considering either styrofoam or foam glass. Unfortunately, the building height is limited due to patio doors. The problem becomes the thickness of the new surface layer. (I would like some insulation on the outside, which is why I don't want to cast slopes).
For waterproofing, asphalt or epdm rubber products are applicable. PVC does not mix with asphalt. There's a jungle here, but if you want to lay the layers yourself, it's probably Mataki Bituthene that applies. The others are welded or heated or poured onto the surface.
Information from a very nice technical support. If you want to lay tiles, Trema 5 is a better choice. The DIY factor is not as high, but it doesn't seem impossible.
http://www.mataki.se/mataki/documents/broschyrer/trema_tm5.pdf
However, 5 mm + tiles is starting to get too thick for me. You want to be able to open the door...
Jonas
http://www.mataki.se/mataki/documents/broschyrer/trema_tm5.pdf
However, 5 mm + tiles is starting to get too thick for me. You want to be able to open the door...
Jonas
System facts about trema 5, including some installation instructions:
http://www.mataki.se/mataki/documents/broschyrer/Systemfakta_UT.inddX.pdf
It looked pretty good except that you might need some special equipment for installation, for example, for welding. It might be just as well to let an expert install it. In my case, it is a fairly uncomplicated geometry and quite small size, so it should go pretty quickly, one would think.
Did their support guy have any opinions on installing it over an old semi-functional waterproofing layer?
http://www.mataki.se/mataki/documents/broschyrer/Systemfakta_UT.inddX.pdf
It looked pretty good except that you might need some special equipment for installation, for example, for welding. It might be just as well to let an expert install it. In my case, it is a fairly uncomplicated geometry and quite small size, so it should go pretty quickly, one would think.
Did their support guy have any opinions on installing it over an old semi-functional waterproofing layer?
I just spoke with their technical support and, as previously mentioned, they were very nice and helpful. He said that:
1. Trema 5 is the correct waterproofing in this case.
2. There will be no problem laying it directly on top of the concrete with the semi-functional waterproofing.
3. You don't want to lay it yourself. At all.
Time to call a contractor, in other words.
1. Trema 5 is the correct waterproofing in this case.
2. There will be no problem laying it directly on top of the concrete with the semi-functional waterproofing.
3. You don't want to lay it yourself. At all.
Time to call a contractor, in other words.
The entrepreneurs in the area at least agree with Mataki on what needs to be done. The estimated price was 350-400 SEK per square meter, which amounts to about 12,000 SEK for my part. Let's see if they can find some time to do the job as well.
One disadvantage they pointed out is that the welded overlap you get when laying the mat will create a rise of about 5mm. So presumably, you will need to grind away some concrete before tiling, but this was apparently included in the above-mentioned price.
One disadvantage they pointed out is that the welded overlap you get when laying the mat will create a rise of about 5mm. So presumably, you will need to grind away some concrete before tiling, but this was apparently included in the above-mentioned price.
I have the same problem as you above... Where my current deck also serves as the roof for the boiler room.
Since the deck is going to be expanded and covered with decking boards, I will probably let the "concrete roof deck" be clad with sheet metal (I haven't checked the cost, but since I have some contacts in this area, I think it will be a cheaper option for me). It will indeed be built more in height than most can handle, but in my case, it will work.
Since the deck is going to be expanded and covered with decking boards, I will probably let the "concrete roof deck" be clad with sheet metal (I haven't checked the cost, but since I have some contacts in this area, I think it will be a cheaper option for me). It will indeed be built more in height than most can handle, but in my case, it will work.
So I’ve hit a snag again. In true craftsman spirit, several people in the area want to do the job, but (reading between the lines) only if they have nothing else to do. They also seem unable to deliver quotes.
Too bad for Mataki, who doesn’t get to sell their nice trema 5 to me, but since they are Good People on their technical support, they recommended an alternative solution with a good bitumen mat if I tile diligently on top. I can lay that myself without a fire-breathing machine. So that’s how it will be.
(How the HELL is it that it’s so impossible to get craftsman help in this country? There clearly seem to be too few craftsmen, even though they should reasonably be able to charge as much as they want in most cases. How is this possible when we have sky-high unemployment? Somewhere here lies a whole kennel buried.)
Too bad for Mataki, who doesn’t get to sell their nice trema 5 to me, but since they are Good People on their technical support, they recommended an alternative solution with a good bitumen mat if I tile diligently on top. I can lay that myself without a fire-breathing machine. So that’s how it will be.
(How the HELL is it that it’s so impossible to get craftsman help in this country? There clearly seem to be too few craftsmen, even though they should reasonably be able to charge as much as they want in most cases. How is this possible when we have sky-high unemployment? Somewhere here lies a whole kennel buried.)