water proofing on terrace

🧱 Waterproofing Quantity & Abstract Sheet
For Given Second Floor & Terrace Areas

Areas provided: Second floor: 11'x7' and 11.25'x15.5'  |  Terrace: 31'x11' and 20.5'x11'. All areas calculated with parapet (2 ft height) and 10% waste.

🛡️ Types of Terrace Waterproofing

1. Liquid Applied Polyurethane (PU) – seamless, high elasticity, UV resistant. Life: 10-15 yrs.

2. Bituminous Membrane (Torch / Self-adhesive) – economical, good for moderate slopes. Life: 8-12 yrs.

3. Cementitious Waterproofing – rigid, ideal for water tanks & balconies. Life: 5-8 yrs.

4. PVC / TPO Membranes – high performance, welded joints, premium. Life: 20+ yrs.

5. Acrylic Coating (Elastomeric) – reflective, easy application. Life: 5-7 yrs.

✅ Our abstract uses Liquid PU coating (₹540/m²) for best results – you can compare with other systems in the table below.

📏 Measurement Sheet – Individual Areas (with Parapet 2 ft height)

Parapet height assumed 2 ft (0.61 m) for all. Drain/extra 1.5 m² added per terrace area separately.

Location	Dimensions (ft)	Floor Area (m²)	Perimeter (m)	Parapet Area (m²)	Drain Extra (m²)	Net Area (m²)	+10% Waste (m²)
Second Floor - 1	11' x 7'	7.15	10.97	6.69	0.75	14.59	16.05
Second Floor - 2	11.25' x 15.5'	16.20	16.26	9.92	0.75	26.87	29.56
Terrace - 1	31' x 11'	31.68	25.60	15.62	1.50	48.80	53.68
Terrace - 2	20.5' x 11'	20.95	19.20	11.71	1.50	34.16	37.58
Total All Areas						124.42 m²	136.87 m²

📐 Calculation formula used:
- Convert feet to meters: divide by 3.28084.
- Floor area = L×W.
- Parapet area = (Perimeter × 0.61 m).
- Drain extra: 0.75 m² for small floors, 1.5 m² for main terraces.
- Total net = floor + parapet + drain. Add 10% for wastage/overlaps.

💰 Abstract Sheet – Liquid PU Waterproofing (for all four areas combined)

System: Primer + PU base coat (2 mm) + UV top coat. Rates: ₹540/m² (inclusive of labour & material).

Item Description	Unit	Quantity (m²)	Rate (₹/m²)	Amount (₹)
Surface preparation & cleaning	m²	136.87	45	6,159
Epoxy/PU primer application	m²	136.87	60	8,212
Liquid PU coating (2 coats, 2 mm)	m²	136.87	325	44,483
Reinforcement fabric at joints	m²	136.87	40	5,475
UV protective top coat	m²	136.87	70	9,581
Total Material + Labour (PU system)				73,910
Extra (scaffolding, waste disposal, misc.)				3,500
Grand Total for all given areas (136.87 m²)				₹ 77,410

⭐ This is for high-quality liquid PU. If you prefer Bituminous torch membrane (₹290/m²), total cost ≈ ₹39,692. For Cementitious (₹170/m²) ≈ ₹23,268. See comparison below.

📊 Comparative Abstract – 3 Waterproofing Systems (Total 136.87 m²)

System	Rate (₹/m²)	Total Cost (₹)	Life (Years)	Best For
Liquid PU (2 mm)	540	73,910 + misc = ₹77,410	12-15	High exposure, seamless roofs
Bituminous Torch Membrane (3 mm)	290	39,692 + misc (₹2000) = ₹41,692	8-10	Budget projects, large terraces
Cementitious (2 coats)	170	23,268 + misc (₹1500) = ₹24,768	5-7	Low-cost, water tanks, balconies

📝 Step-by-step sample: Terrace 1 (31'x11')

• Dimensions: 31 ft × 11 ft → in meters: 9.45 m × 3.35 m.
• Floor area: 9.45 × 3.35 = 31.66 m².
• Perimeter: 2×(9.45+3.35) = 25.6 m.
• Parapet area (height 0.61 m): 25.6 × 0.61 = 15.62 m².
• Drain & edge extra: 1.5 m².
• Net area: 31.66 + 15.62 + 1.5 = 48.78 m² → with 10% waste = 53.66 m².
• PU cost: 53.66 × 540 = ₹28,976 for this terrace alone.

Same method applied to all other areas.

📖 Relevant Indian Standards (IS Codes) for Waterproofing

• IS 15801:2008 – Polymer modified bituminous membrane for waterproofing
• IS 15695:2008 – Liquid applied polyurethane waterproofing coating
• IS 1200 (Part 15):1987 – Method of measurement of building works: waterproofing
• IS 2643:1975 – Code of practice for waterproofing of roofs with bitumen felt
• IS 3067:1988 – Specification for epoxide resin based waterproofing compounds

❓ Top 10 FAQs about Terrace Waterproofing

1. What is the best waterproofing method for my terrace?
Liquid PU is best for longevity and seamless finish. Bituminous is budget-friendly.

2. How do I calculate waterproofing area correctly?
Use: (L×W) + (perimeter×parapet height) + 1 to 1.5 m² for drains + 10% waste.

3. What thickness is required for PU coating?
Minimum 1.5 mm dry film, recommended 2 mm for terraces.

4. Is cementitious waterproofing enough for terrace?
Not recommended for large terraces with thermal movement – it may crack. Use for small balconies or water tanks.

5. What is the cost of PU waterproofing per square foot?
Approx ₹50–₹55 per sqft (₹540/m²).

6. Do I need to remove old waterproofing before new application?
Yes, loose material must be removed; surface must be clean and primed.

7. How long does terrace waterproofing last?
PU: 12-15 years; Bituminous: 8-10; Cementitious: 5-7.

8. Which IS code covers measurement of waterproofing works?
IS 1200 Part 15.

9. Can I apply PU waterproofing myself?
Professional application recommended; requires precise mixing and thickness control.

10. How do I get an accurate abstract sheet for my project?
Use our measurement table, input your areas, multiply by rates, and add 10-15% contingencies.

🧮 Custom Waterproofing Calculator (Any Area)

Length (feet): Width (feet): Parapet height (feet): Waterproofing type: Liquid PU (₹540/m²) Bituminous (₹290/m²) Cementitious (₹170/m²)

📋 Your Estimate

Net Area (m²): --

With 10% waste: -- m²

Total Cost: ₹ --

*Includes primer+coating+labour. Excludes GST (18%) and extra reinforcement.

© 2026 Civil Engineering Hub – Waterproofing Estimation Tool | Based on IS 15801 & IS 15695.
Rates are indicative for May 2026. For exact quote, contact local applicators.