Is 2 days for a 4" concrete base to dry before applying a cement render screed layer and then for tiling to start the following day sufficient for the concrete and screed to dry in our type of climate?
To be clearer screed layer done on Thursday, tiling on Friday.
Forgot to add for car porch

This post has been edited by atilla: Sep 16 2025, 12:42 PM

ChatGPT.

Thanks for clarifying — you're talking about a **4-inch (100 mm) thick concrete slab base** for a **car porch**, with a **cement render screed** applied on top, and then **tiling the next day**.

Here’s the important part:

### 1. Concrete base drying/curing

* A 4" (100 mm) concrete slab does **not fully cure in 2 days**.
* Standard curing guidance: concrete gains about **70% strength in 7 days**, and full curing takes **28 days**.
* At just 2 days, the slab is still "green" (weak, high moisture content). Laying screed or tiles too early risks **cracking, debonding, or tile pop-ups**.

### 2. Screed curing

* A cement render screed (say 20–40 mm thick) also requires curing.
* General guideline: screed needs about **1 week per cm thickness to dry** before covering with tiles, unless a special fast-drying additive is used.
* Tiling the very next day on a fresh screed is **not recommended** in normal conditions.

### 3. Car porch considerations

* Car porches need to handle **heavy loads (vehicles)** and **exposure to weather**.
* Any trapped moisture under tiles can cause **hollow sounds, lifting, or efflorescence** once cars roll over them.

### 4. Exceptions

* If your contractor is using a **polymer-modified rapid-set screed** and a **flexible tile adhesive designed for green concrete/screed**, then fast-tracking is possible.
* Without those products, the traditional system needs **weeks, not days**.

---

✅ **Best practice recommendation:**

* Allow the **concrete slab to cure at least 2–3 weeks** before screeding.
* Allow screed to cure properly (often 7–14 days minimum) before tiling.
* Use curing compounds or cover with plastic sheets to avoid surface cracking.

⚠️ **If you tile on Friday after screeding Thursday over a 2-day-old slab, you risk serious failures in the future.**

---

Would you like me to suggest **fast-track alternatives** (like rapid-set screeds and adhesives) that could safely shorten the timeline?

I should've posted that I'm more interested in what is normal practise in Malaysia not chatgpt answers which may not apply in our context.

then youre suppose be smarter to check with proper concreter than asking randomly on internet.

Please disregard everybody here.

You have to follow ISO standard of curing concrete.

There is a compliance documentation centered towards it.

2 to 3 weeks ? Yr contractor wont entertain u

best practice is 14 days min.

Contractor won't wait till it is fully cure.
I would say 2 weeks but they will just get it done within few days

2 weeks

Follow manufacturer instructions, can be weeks, but contractor no fuck one JALAN saja

They’re paid by job done not daily

Find a proper contractor, not cap ayam one

Proper way:

Concrete casting
Screed no need since you going to tile, you need a rough surface
Wait 2 to 4 weeks
Tile it.

By right u need wait 4 weeks to cure, but some especially ready mix concrete will reach 28 days strength in 14 days.

If ur client, you should enforce the proper method else risk cracking tiles popping, who's paying the money?

If ur contractor, u should do that too, else risk redo / reputation, viral, tribunal, even if no contract signed, the law ensures work is properly done.

Is better if you can water the concrete slab daily starting from 24 hours after finish casting

This post has been edited by dest9116: Sep 17 2025, 11:13 AM

u pay contractor idling, they can wait for you 14 to 28 days also can.

or u give them work order do something else while waiting for curing.

but in real life, ask contractor do wet lay on screed (use mortar not adhesive), 3 day curing between laying screed and tiling ok already.



This post has been edited by Redhunt: Sep 17 2025, 12:50 PM

You're right but this is on the ground floor. Non load bearing surface. I'm leaving the area empty until the concrete is properly cured.

Yes, I'm just going by what is acceptable so long as problems don't occur. I'll leave the area empty for a few days of curing.

delete

This post has been edited by atilla: Sep 18 2025, 11:46 AM

delete

This post has been edited by atilla: Sep 18 2025, 11:45 AM