Member
· Stockholms
· 1 555 posts
I have some craftsmen here who have broken up the basement floor, dug out 30 cm, replaced the drainpipes, leveled with leca, insulated with polystyrene 2x7 cm, laid underfloor heating loops and reinforcement mesh.
Today they poured the new floor with Byggmax Gjuta Grov. Tomorrow they want to lay self-leveling compound on top, and the day after that, they want to lay wood flooring with foam as soundproofing.
When I asked them if you can really lay wood flooring two days after pouring, they laughed at me for being silly. There was no problem at all, and they had done it this way a hundred times before.
I thought that regular concrete took a couple of days to cure and then should preferably dry out for a month or three. Am I completely wrong?
Today they poured the new floor with Byggmax Gjuta Grov. Tomorrow they want to lay self-leveling compound on top, and the day after that, they want to lay wood flooring with foam as soundproofing.
When I asked them if you can really lay wood flooring two days after pouring, they laughed at me for being silly. There was no problem at all, and they had done it this way a hundred times before.
I thought that regular concrete took a couple of days to cure and then should preferably dry out for a month or three. Am I completely wrong?
The problem is the moisture in the concrete. You have to measure the moisture content in the concrete before flooring! It should be below 90% to my understanding, usually about 12-16 weeks are expected before you can install flooring. Your workers don't seem to know their stuff, so stand your ground. Don't let them lay the flooring now.
It doesn't hurt to measure moisture.
Today's construction activities focus on squeezing time and costs. In many cases, the manufacturer's drying reference is completely ignored.
It doesn't have to go wrong, but it can. And that should really be enough to pause if you don't conduct a measurement or refer to the product information.
There are fillers that dry 1mm per day and 10mm per day.
Today's construction activities focus on squeezing time and costs. In many cases, the manufacturer's drying reference is completely ignored.
It doesn't have to go wrong, but it can. And that should really be enough to pause if you don't conduct a measurement or refer to the product information.
There are fillers that dry 1mm per day and 10mm per day.
I believe them 100%Fred vom Jupiter said:
In their place, I would have used quick-drying compound, e.g., Weber Floor 4040 Rapid, as it doesn't seem to involve depths greater than 10 cm (?)
"Floor 4040 is ready for covering after about 2 hours, provided that the floor covering withstands at least 85% RH. The specified drying time assumes a good drying climate with +20 °C, 50% RH, and some air exchange."
But regardless of what is used, you will have elevated humidity throughout the room for several days (dehumidification must not be used during self-leveling) and if you then add the floor manufacturer's recommendations that the floor should be placed in the space where it will finally be laid, it is likely to cause problems. No is the answer, lay the floor in a few weeks when the moisture level is right.
4040 is not a self-leveling compound but a slope-building or smoothing compoundisolde said:I believe them 100%
In their place, I would have used fast-drying leveling compound, e.g., Weber Floor 4040 Rapid, as it doesn’t seem to involve depths greater than 10 cm (?)
"Floor 4040 is open for covering after about 2 hours, provided the floor covering can withstand at least 85% RH. The specified drying time presupposes a good drying climate with +20 °C, 50% RH, and some ventilation."
use it and you'll be sanding for hours or re-level with a self-leveling compound
Member
· Stockholms
· 1 555 posts
It is Byggmax grovbetong about 7 cm that was cast today and they want to apply a few mm of leveling compound tomorrow.
I think the leveling compound dries quite quickly, it's the concrete underneath that I'm concerned about. But maybe it can dry downwards? It's not completely sealed in the insulation with all the joints.
I think the leveling compound dries quite quickly, it's the concrete underneath that I'm concerned about. But maybe it can dry downwards? It's not completely sealed in the insulation with all the joints.
Member
· Stockholms
· 1 555 posts
How could you guess that? Czechia actually.
There are no Swedish craftsmen working with byggmaxbruk if I may generalize; I'm not saying anything good or bad about it, that's just how I perceive it. I think there is floor foam that is for newly poured concrete; I saw one at Bauhaus that was white and knotty.
It does depend somewhat on the substrate beneath the concrete as well.
The moisture needs to dry out somewhere. Either downward if the ground absorbs it, or upward.
Since you have styrofoam underneath, it will be relatively sealed in that direction.
If you lay laminate or wooden flooring, it will act as a barrier and absorb some moisture. The rest will have trouble drying out, risking keeping the wall or floor construction damp for a long time, which increases the risk of future mold or rot damage in the worst case.
The moisture needs to dry out somewhere. Either downward if the ground absorbs it, or upward.
Since you have styrofoam underneath, it will be relatively sealed in that direction.
If you lay laminate or wooden flooring, it will act as a barrier and absorb some moisture. The rest will have trouble drying out, risking keeping the wall or floor construction damp for a long time, which increases the risk of future mold or rot damage in the worst case.