How to best convert a space with an uninsulated slab into living space?

[Rättochfel]

Hello! I have an attached garage that was built at the same time as the house in the early '60s. The house has a raised floor in some way, and it seems to work well! The garage's dimensions might have matched the standards back then, but it's challenging to use as a garage today because cars have probably grown, especially in height, so maybe a convertible can fit through the opening. The ceiling height isn't too generous either. The plan is to install a bathroom and make the rest into a small bedroom! The problem is the uninsulated slab! There's a lot of rock on the property, so I don't think it's possible to break up the floor and excavate without removing rock! The slab currently shows no signs of moisture infiltration. However, it's likely never been a heated space. The surrounding walls are plastered stone. Does anyone have a good solution without tearing everything down and starting over or blasting down 😆

 

[Jonatan79]

Hi! I have an extended garage that was built at the same time as the house in the early 60s.
The house has a raised floor in some way and it seems to work well! The garage dimensions might match the standards of that time but it becomes difficult to use as a garage today because the cars have probably grown, especially in height, it would probably be fine for a convertible to fit through the opening. The ceiling height is also not very generous.
The idea is to install a bathroom and make a small bedroom out of the rest of the space!
The problem is the uninsulated slab! There is a lot of rock on the plot, so I don't think you can chisel away the floor and excavate without removing rock! The slab currently shows no signs of moisture intrusion. However, it has likely never been a heated space. Plastered stone walls all around.
Does anyone have a good solution without tearing everything down and starting over or blasting your way down 😆

Rock is the best foundation. You can for example install electric floor heating in the bathroom to add a little luxury. How much are the raised floors insulated, are they cold?

 

[Rättochfel]

Perhaps not fully understanding your response! Electric underfloor heating in the bathroom- what's your thinking regarding the waterproofing layer then?
I think the house is well structured, 200-300 mm, and I also believe that the majority of (drain pipes go over the slab). But I am satisfied with the existing floor in the house (for the moment 😀)
It's the garage floor that is without any insulation.

 

[Jonatan79]

Ok. Then I'm with you. You can install electric coils in the future bathroom, apply self-leveling compound on this, and, for example, tiles as the surface layer. Without rising moisture, a regular waterproofing membrane is suitable for the bathroom. For the remaining floors, you can, for example, install a solid wood floor, not cheap laminate which becomes ice-cold.

 

[Rättochfel]

Yes, I understand! Ventilated floor is not something you recommend?
I was considering casting everything up with about 5 cm of EPS-cement. Could that help without causing damage?

 

[Jonatan79]

Yes, I understand now! Ventilated floors are not something you recommend?
I was considering pouring everything up with about 5 cm of eps-cement. Could that help without causing damage?

Why?

 

[Rättochfel]

A ventilated floor is considered a "safe" solution for an uninsulated slab. It probably has no drawbacks except for the cost. It is unclear if moisture will come up or not. Maybe a little, but if it becomes a problem after, say, 10 years, it's not certain. The ventilated floor also creates some insulation, which can be an advantage. Nowadays, it doesn't need to be built much, which is also good in this case (ceiling height). But the combination on the same floor I haven't heard of before. Does anyone know?
The solution with EPS might be a middle ground that works for the entire surface, or is that a misconception?

 

[Jonatan79]

Ventilated floors are generally considered a "safe" solution for uninsulated slabs. It doesn't really have any disadvantages other than the cost. It's unclear if moisture comes through or not. Perhaps a little, but whether it becomes a problem after, say, 10 years is not certain. The ventilated floor also provides some insulation, which can be an advantage. Nowadays, it doesn't need to be built up much, which is also good in this case (ceiling height). But the combination on the same floor is something I haven't heard of before. Anyone know?
The solution with EPS might be a middle ground that works for the entire area, or is that a misconception?

What ceiling height do you have today? Ventilated floors obviously insulate, but they are also a cost.

 

[Rättochfel]

Ceiling height is today 210.

 

[BirgitS]

Then you probably don't want to build upwards at all. Skip underfloor heating and have a ventilated wall-to-wall carpet intended for basements in the bedroom.

 

[cpalm]

Why?

The obvious reason is that you don't want to heat the place for the crows? Or rather the mountain trolls in this case.

 

[Jonatan79]

The obvious thing is that you don't want to "elda för kråkorna"? Or rather "bergstrollen" in this case.

Sure, if it were normal ceiling height and a permanent residence. Now it doesn't seem to be so.

 

[Rättochfel]

Yes, it will be permanent housing! Electric heating doesn't build much, the waterproof layer, tiles in the bathroom, and the rest solid wood flooring is a proposal I understand! Ventilated carpeting- I'm not familiar with, but if it's like Platon and then on with, for example, wood flooring sure, I also understand, but in the bathroom how was the idea there, pour over and tiles? In that case, won't there be a big difference in mm to the other! You can probably take a little from the ceiling height, it's not the newest ceiling😀! Has anyone used Eps-cement in these contexts? Then the mountain troll won't notice it's living under a sauna😀

 

[BirgitS]

Ventilated carpet - I don't know about that, but if it's like Platon and then on with, for example, wooden flooring, sure, I understand that, but in the bathroom, what was the idea there, pour over and tiles?

A ventilated carpet allows moisture to pass through, meaning it doesn't have a plastic layer at the bottom. At building supply stores, you can ask for a carpet for basements with moisture.

A bathroom vinyl flooring builds less height and doesn't feel as cold as tiles.

 

[Rättochfel]

No, it is still unclear what the idea is! Ok, simple matta but the våtrumsmatta does not let moisture through or is it a special one you had in mind?