Hello!
We are puzzled. In October, we made a concrete slab as a patio, and on it, two walls were built and plastered. We wanted the walls without metal sheets (as they look in Greece), but were informed that this is not possible in Sweden due to too much rain. We then decided to have roof tiles on top instead. After a few days, one of the carpenters said that you could add "Sica" to the mortar at the top, and in this way, the water would be prevented from entering the mortar, and that this would be sufficient. We said "sure, let's do that," and it was done. Now the company is bringing a paper they want us to sign to exempt him from any complaints because this is a risk construction; he also says that the concrete slab itself is a risk construction as there is no roof over it. Does anyone here know anything about "Sica" and if it's bad to have a concrete slab outside without a roof over it? Furthermore, the builder has charged us for over 40 hours that the workers have not been here, he says it takes time to clean the wood used for the slab molds. Can it really take that long? Does anyone know?
We are puzzled. In October, we made a concrete slab as a patio, and on it, two walls were built and plastered. We wanted the walls without metal sheets (as they look in Greece), but were informed that this is not possible in Sweden due to too much rain. We then decided to have roof tiles on top instead. After a few days, one of the carpenters said that you could add "Sica" to the mortar at the top, and in this way, the water would be prevented from entering the mortar, and that this would be sufficient. We said "sure, let's do that," and it was done. Now the company is bringing a paper they want us to sign to exempt him from any complaints because this is a risk construction; he also says that the concrete slab itself is a risk construction as there is no roof over it. Does anyone here know anything about "Sica" and if it's bad to have a concrete slab outside without a roof over it? Furthermore, the builder has charged us for over 40 hours that the workers have not been here, he says it takes time to clean the wood used for the slab molds. Can it really take that long? Does anyone know?
What they have used is probably Sica 1. http://swe.sika.com/sv/solutions_products/02/02a015/02a015100/02a015105.html
Then charging 40 hours for washing formwork is pure scam.
Then charging 40 hours for washing formwork is pure scam.
1. There are many variations of SIKA as an additive, and you haven't mentioned which one was used, so I can only provide a general answer. Yes, you can use SIKA to "seal" against penetrating water by mixing the additive into the mortar.
2. It is not a good construction of a wall when there is no flashing on the top, so flashing is always preferable.
3. The concrete slab should be cast with additives to ensure a frost-resistant construction, which the builder should naturally understand. He orders this from the concrete factory, informing them that he wants it, so they deliver such concrete.
4. The cost of formwork should naturally be included in the price. And regardless, it cannot take 40 hours to clean the formwork; otherwise, one might as well have bought the wood and discarded it after casting. A week's work corresponds to approximately 15,000-20,000 kronor. Which would buy a lot of wood.
So the answer is that the builder should be able to guarantee his slab against frost, and you should get a warranty on this. It is absolutely not a risk construction!!
You should ask to know which concrete was used and its exposure class.
It should be XF3 concerning frost resistance. It is stated on the delivery note he received when the concrete was delivered to the site.
The price for cleaning the formwork is unreasonable. (But what agreement did you have from the start?)
A wall without sheet metal flashing does have certain risks, so he is right about that.
2. It is not a good construction of a wall when there is no flashing on the top, so flashing is always preferable.
3. The concrete slab should be cast with additives to ensure a frost-resistant construction, which the builder should naturally understand. He orders this from the concrete factory, informing them that he wants it, so they deliver such concrete.
4. The cost of formwork should naturally be included in the price. And regardless, it cannot take 40 hours to clean the formwork; otherwise, one might as well have bought the wood and discarded it after casting. A week's work corresponds to approximately 15,000-20,000 kronor. Which would buy a lot of wood.
So the answer is that the builder should be able to guarantee his slab against frost, and you should get a warranty on this. It is absolutely not a risk construction!!
You should ask to know which concrete was used and its exposure class.
It should be XF3 concerning frost resistance. It is stated on the delivery note he received when the concrete was delivered to the site.
The price for cleaning the formwork is unreasonable. (But what agreement did you have from the start?)
A wall without sheet metal flashing does have certain risks, so he is right about that.
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Thank you for all the answers! The initial agreement was that it would take 1 week's work for two people to cast two slabs, one about 70 m2 and one about 12 m2, as well as build two walls with plaster. Initially, the agreement was to lay roof tiles on top, but then they suggested we use SIKA, and we agreed to this believing they knew what they were doing. The completion time ended up being 174 hours instead of 80. As I understand it, we should lay tiles on top. Or is that also bad? Should it be metal? On the day the concrete truck came, the workers were here for a couple of hours assisting when the concrete was pumped out. Then they came, and as we understood it, they checked the concrete 3 - 4 times during the day, they were here a maximum of 20 minutes each time for two people. This day we are charged a total of 21 hours; is this reasonable? We are wondering why there are two people checking the concrete and if it is really okay for us to pay for so many hours when no direct work is done.
I want to add that they have charged 39 hours to build molds, one at 12 m2 and one at 70 m2, they have been built against the house and the ground was prepared with gravel before. Then comes the concrete and they are here for a couple of hours and help with unloading but then come as we understand it to "check the concrete." Can that be correct? Then they grind the slabs the next day, this takes 20 hours (they are also gone for long periods this day). A wall of 5 meters with a corner and continuation of about 1.5 meters takes 20 hours to build. A SIKA layer is applied on top as a form. The next wall of 8 meters takes 8 hours to build, that day a few bags of plaster are picked up and we are charged 2 hours for that. Plastering the wall with the corner takes 20 hours. Plastering the wall which is straight and 8 meters + SIKA layer and picking up and transporting home tools and concrete mixer (1 km) takes 37 hours. Does this seem reasonable to anyone out there who knows, we don't know if we might be slightly overcharged...?