How does primer work?

[zaxter]

Hello!

I am planning to build a laundry room with both tiles and terracotta tiles in the basement of my house built in 1935. There is no insulation either under the floor or behind the wall. It was drained 25 years ago, though. The plan is to insulate the exterior with isodrän next summer.

What I have understood is that it is very important not to block moisture migration. From what I have gathered, you should not have a moisture barrier. But everywhere I read, it's recommended to use primer both under and over the leveling compound. Doesn't the primer block moisture migration???

Grateful for help!

Best regards, Zax

 

[zaxter]

It will probably be done without primer.

1. Uninsulated lättbetong
2. Casco Husfix
3. Casco Multifix directly on
4. Tiles

Will this hold, do you think???

 

[synpunkter]

Regular primer is not diffusion-tight. However, there are moisture barrier products called primers that should be used before the regular moisture barrier compound, and this primer is somewhat diffusion-tight. But as mentioned, regular primer is not. I don't believe in DIY fixing for cost reasons, among others. Search the forum and you will find answers. Render or gypsum plaster should be the answer.

 

[danielvestling]

Whichever primer you use, it is IMPORTANT that primer/fix/sealant comes from the same supplier. It's worth mentioning this once again.
After all, you are working with chemicals and they need to work together. So, you can't just buy the cheapest here and the cheapest there.

Keep that in mind

//Daniel