Hi.
I have tried to ask this question in the Flooring section but haven't received a response. Therefore, I'm trying here.
We have removed the old subfloor in our storage room. The old one consisted of double particle boards lying directly on the asphalt floor, and on top of the particle boards, double layers of vinyl flooring... It didn't smell like roses and didn't look so pleasant.
Now we want to install a new floor on top of the asphalt and are considering which options are available for a durable solution without moisture problems. I'm considering two options:
1. Drainage mat underneath, with particle boards and vinyl flooring on top, ventilated baseboards, or alternatively, a raised floor with ventilated baseboards.
2. Moisture-protective plastic film on the asphalt and on top of that particle boards or alternatively a raised floor. (Will a solution with plastic film be sufficient?)
The asphalt is not even, and in the instructions for laying the drainage mat, it states that the substrate must be even with a difference of no more than +-2mm/2m. Is it crucial for the function? Otherwise, I thought that the differences could be adjusted with shims in a raised floor on top of the drainage mat. Otherwise, the asphalt needs to be leveled, which seems to require specially adapted leveling compound with cleaning of the asphalt and priming before application, phew... I saw in an instructional video that you can use kiln-dried sand to fill in holes in concrete, can you use it on asphalt as well?
Many questions and considerations on one subject, hope that someone out there has a good and simple solution!
Best regards, Andreas.
I have tried to ask this question in the Flooring section but haven't received a response. Therefore, I'm trying here.
We have removed the old subfloor in our storage room. The old one consisted of double particle boards lying directly on the asphalt floor, and on top of the particle boards, double layers of vinyl flooring... It didn't smell like roses and didn't look so pleasant.
Now we want to install a new floor on top of the asphalt and are considering which options are available for a durable solution without moisture problems. I'm considering two options:
1. Drainage mat underneath, with particle boards and vinyl flooring on top, ventilated baseboards, or alternatively, a raised floor with ventilated baseboards.
2. Moisture-protective plastic film on the asphalt and on top of that particle boards or alternatively a raised floor. (Will a solution with plastic film be sufficient?)
The asphalt is not even, and in the instructions for laying the drainage mat, it states that the substrate must be even with a difference of no more than +-2mm/2m. Is it crucial for the function? Otherwise, I thought that the differences could be adjusted with shims in a raised floor on top of the drainage mat. Otherwise, the asphalt needs to be leveled, which seems to require specially adapted leveling compound with cleaning of the asphalt and priming before application, phew... I saw in an instructional video that you can use kiln-dried sand to fill in holes in concrete, can you use it on asphalt as well?
Many questions and considerations on one subject, hope that someone out there has a good and simple solution!
Best regards, Andreas.
I would have laid 5-10cm insulation blocks as tightly as possible and on that a vapor barrier (plastic film) to separate the cold asphalt floor from potentially humid warmer storage air, and on that chipboard.
Platon mat can be an idea under the insulation blocks if the asphalt can get wet for any reason. If it's just a matter of temperature differences, the Platon mat is not needed.
/CC
Platon mat can be an idea under the insulation blocks if the asphalt can get wet for any reason. If it's just a matter of temperature differences, the Platon mat is not needed.
/CC
Thanks for the tip! I thought that perhaps ground moisture was continuously rising from the asphalt and that the moisture needed to be ventilated away using Platon and ventilated baseboards. But if this isn't necessary, it would be very easy to do as you suggested. Can you ignore the fact that the asphalt is a bit uneven then? What are isolation blocks? Can you use cellplast instead?
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Thank you Chris! What do you think about rising ground moisture from the asphalt? Is this not a problem so I can safely ignore Platon and vented baseboards? Was it the temperature difference (condensation) that caused the old particle boards to mold?
Best regards, Andreas.
Best regards, Andreas.
When building a slab on grade, whether using a heated foundation or not, the insulation is placed on 0/8 gravel, which is draining, followed by a vapor barrier and then the concrete. If water does not run on your asphalt, the same construction method should work in your case.
Chipboard is an organic material, and if it comes into contact with moisture, mold can easily form. This is prevented with a plastic layer. The ground is always colder than the room, which is why you also need the insulation that isolates against the substrate. Cold ground air meets warmer room air more slowly, preventing condensation.
/CC
Chipboard is an organic material, and if it comes into contact with moisture, mold can easily form. This is prevented with a plastic layer. The ground is always colder than the room, which is why you also need the insulation that isolates against the substrate. Cold ground air meets warmer room air more slowly, preventing condensation.
/CC
Ok, thanks! I am really motivated to try and see if this method works. I quickly looked at the asphalt and it seems to be fairly even in the middle, but after the walls, it "rises" quite a lot which causes a slope from the wall of a few centimeters over a 2m length. 
I'll have to take a closer look when I get the chance to clear all the stuff out of the storage ...
Best regards, Andreas
I'll have to take a closer look when I get the chance to clear all the stuff out of the storage ...Best regards, Andreas
If you need to level the surface, it must be done with plastic, stone, or other inorganic materials. I would probably level the surface on top of the plastic. If there is a difference of as much as 2 cm, the easiest might be to cut long wedges from a wooden stud. It doesn't hurt to also create an air gap between the plastic and the floor chipboards in this way.
/CC
/CC