Filling joints in a thin concrete ceiling - with what

Hello,

I am now facing the annoying question in my new building: "How do I properly fill the joints in the concrete ceiling?" I am currently still a novice in this field but not really unskilled.

I need a few professional tips.

1. How and with what should I apply the first filler? – That is, how deep and with what kind of material?

2. How and with what should I apply the final filler?

3. How and when should reinforcement tape be embedded?

When, how, and where do I place this so that it is not sanded off? I think at least that this happens if I lay it flush on top of the joint. After step 1 or step 2...???

4. What grit size should be used to sand the joints?

5. With what should the pores in the concrete ceiling be filled, and does the ceiling need to be primed beforehand?

Many thanks in advance for the helpful tips.

Best regards and have a nice holiday

Michael

Hi!

Another post gone - so here’s the short version:
1st, 2nd, and 5th: Plaster with plastic content.
3rd and 4th: Not at all; burrs are scraped off.

I always prime. Can’t hurt, costs nothing.

Regards,
Tom.

Hello,

I am now facing the tedious question in my new building: "How do I properly fill the joints in the concrete ceiling?" At the moment, I am still a novice in this field but not really inept.

I would need some professional tips here.

1. How and with what to pre-fill? - That means how deep and with what kind of material?

2. How and with what to re-fill?

3. How and when to embed reinforcement strips.

When, how, and where should I place these so they are not sanded off? I at least think this will happen if I put it flush on top of the joint. After step 1 or step 2 ...???

4. What grain size should be used to sand the joints?

5. With what should the pores in the concrete ceiling be filled, and does the ceiling need to be primed beforehand?

Many thanks in advance for the helpful tips.

Best regards and have a nice holiday,

Michael

According to your description, you have a hollow core ceiling that is prestressed on the top side and not grouted. Get a professional for this, as these elements retain condensation in the hollow cores for a very long time and exhibit long shrinkage behavior. I have had problems after 2 years with Dennert ceilings.