Why is external plaster thicker?

To provide better resistance against rain and weathering in severe climates like Nepal's monsoon. It is often done in two coats (12mm + 8mm).

What is the curing time for external plaster?

It should be cured for at least 10 days to reach its design strength and minimize hairline cracks.

Need to paint the exterior?

If you want full estimate for weather-coat painting → [Exterior Paint Calculator](/exterior-paint-calculator/)

Why 6mm thickness for ceiling?

To minimize the weight of the plaster so it does not sag or fall from the concrete slab.

Recommended curing for ceiling plaster?

Curing should be done for 7 days. Vertical surfaces and ceilings require extra care to keep moist.

Planning false ceiling instead?

If you want full estimate for false ceiling boards → [False Ceiling Calculator](/false-ceiling-calculator/)

Advantage of gypsum plaster?

It is direct-to-wall, requires no curing, is fire resistant, and provides a much smoother finish than cement plaster.

Internal Plaster External Plaster Ceiling Plaster Gypsum Plaster

Quality Inspector

Plastering Work

Plaster & Wall Putty Calculator (Finishing Tools Nepal)

Expert Guide

Find material quantities for internal wall plastering.

Worker plastering wall with trowel on construction site

⚡ Quick Answer

For a typical 100 sq.ft internal wall with 12.5mm plaster (1:5 ratio), you need approximately 5 bags of PPC/OPC cement and 25 CFT of sand typical for Nepalese construction.

🛠️ How It Works

Mortar Volume = Area × Thickness. Dry Volume = Wet Volume × 1.33. Materials calculated by ratio. Now calculate Wall bricks here → Brick Calculator

Measure the total wall area in square meters.
Deduct the area of doors, windows, and other openings.
Choose your desired plaster thickness (standard in Nepal is 12.5mm for internal brick walls).
Select the cement-sand mix ratio (e.g., 1:4 or 1:5).
The calculator accounts for a 33% dry volume expansion of mortar.

📐 Calculation Formula

Volume = Area × Thickness × 1.33

📋 Real-Life Example

50 m² wall, 12mm thick (1:4 ratio):
• Volume = 0.6 m³ wet → 0.8 m³ dry
• Cement ≈ 4.6 bags

⚠️ Common Mistakes to Avoid

Forgetting to subtract door and window areas from the total wall area.
Using sand with high silt content, which leads to shrinkage cracks. Most people forget this sand check → Sand Quantity Calculator
Applying a thick single coat instead of maintaining standard 12mm-15mm thickness.
Ignoring the 33% dry volume factor when estimating raw materials.

❓ Frequently Asked Questions

What is the standard thickness of internal plaster?

Internal plaster is usually 12mm-15mm (1/2 inch) thick on brick surfaces and 6-9mm on concrete surfaces.

How long should plaster be cured?

Cement plaster must be cured for at least 7 to 10 days by keeping the surface moist with water to prevent cracks and ensure full strength.

Estimate painting too?

If you want full estimate for interior wall painting → [Interior Paint Calculator](/interior-paint-calculator/)