Summer in India means one thing for most households and offices — a new AC is going up on the wall. But before the technician even touches the indoor and outdoor units, there's a step many people forget to budget for: core cutting. Whether you're installing a sleek split AC or a compact window AC, someone has to cut a clean, precise hole through your wall for the pipes, wires, and drainage to pass through. That job comes with its own charges, tools, and skill requirements — and the price can vary quite a bit depending on the type of AC, the wall material, and the city you live in.
At Core Cutting India (corecuttingindia.com), we get dozens of calls every AC season asking the same question: "Why does core cutting cost extra when the AC company is already charging installation fees?" This blog breaks down exactly what core cutting charges cover, how Split AC and Window AC installations differ, and what a fair price looks like across Indian cities in 2026.
What Is Core Cutting in AC Installation?
Core cutting is the process of drilling a round, clean hole through a concrete, brick, or RCC (Reinforced Cement Concrete) wall using a diamond core cutting machine. For split ACs, this hole allows the copper refrigerant pipes, power cable, and drain pipe to pass from the indoor unit to the outdoor unit. For window ACs, a larger rectangular or square opening is usually needed to fit the unit itself into the wall or window frame.
Unlike an ordinary hammer drill, a core cutting machine uses a diamond-tipped cutting bit and often water cooling to bore through hard surfaces like RCC slabs without cracking the wall, damaging rebar, or leaving jagged edges. This is precision work — especially in high-rise apartments in cities like Mumbai, Gurugram, or Bengaluru, where walls are load-bearing RCC and a bad cut can compromise structural safety.
Split AC vs Window AC: Why Core Cutting Needs Differ
Split AC Core Cutting Requirements
A split AC has two separate units — the indoor unit mounted on an interior wall, and the outdoor condenser unit fixed outside on a stand or bracket. Connecting them requires:
- A 2 to 3 inch diameter hole drilled through the wall for copper pipes, drain pipe, and wiring
- Precise angling (slightly sloped outward) so condensate water drains properly instead of seeping back indoors
- Careful positioning to avoid electrical conduits or plumbing lines hidden inside the wall
Because most modern Indian homes and offices are built with RCC walls (10 to 23 cm thick), this small-diameter hole still requires a proper diamond core cutting machine. A regular impact drill simply cannot cut through reinforced concrete cleanly, and attempting it often cracks tiles, plaster, or the wall's outer finish.
Window AC Core Cutting Requirements
Window ACs are typically fitted into an existing window opening or a purpose-built wall recess, so in many older buildings no cutting is needed at all — the unit simply slides into the window frame. However, in newer apartments and offices where there's no traditional window slot, a larger rectangular or square core cut (often 45 x 60 cm or as per the AC model) is required to embed the unit directly into the wall.
This is a bigger, heavier job than the small round hole needed for a split AC, involving more cutting length, more manpower, and sometimes additional support structure (an angle iron frame or bracket) to hold the AC's weight once it's set into the wall.
Core Cutting Charges Compared: Split AC vs Window AC
| Parameter | Split AC | Window AC |
|---|---|---|
| Type of cut | Round hole, 2–3 inch diameter | Rectangular/square opening, larger size |
| Wall material impact | RCC/brick — moderate difficulty | RCC/brick — higher difficulty due to size |
| Average charge (per unit) | ₹400 – ₹900 | ₹1,200 – ₹2,500 |
| Time required | 15 – 30 minutes | 45 minutes – 1.5 hours |
| Tools used | Diamond core drill bit (2–3 inch) | Diamond core drill + chiseling/cutting tools |
| Additional work | Minimal patch-up/sealing | Frame support, larger patch-up, waterproofing |
| Structural risk | Low, if done by professionals | Moderate — more caution needed near rebar |
Note: Prices are indicative and vary by city, wall thickness, floor height, and whether scaffolding or a ladder is required for outdoor-facing walls.
As the table shows, window AC installation generally costs more for core cutting than split AC installation, simply because the opening required is significantly larger and involves more precision to avoid damaging the wall's structural integrity.
Factors That Affect Core Cutting Charges in India
Several variables influence what you'll actually pay, and it's worth understanding them so you don't get overcharged or undercharged (which can mean corners are being cut, literally):
1. Wall Type and Thickness RCC walls, especially load-bearing ones in high-rises, cost more to cut than simple brick or block walls. A 23 cm RCC wall in a Gurugram high-rise will cost noticeably more than a 10 cm partition wall in an older Chennai bungalow.
2. Floor Height and Accessibility Core cutting on the 15th floor of a Mumbai tower, where the technician needs safety harnesses or a hydraulic ladder to access the outdoor wall, costs more than a ground-floor home in a Lucknow colony.
3. Number of Holes/Cuts If you're installing multiple ACs — say, three split ACs in a 3BHK Bengaluru flat — most core cutting contractors offer a discounted rate per additional hole after the first.
4. City and Local Labour Rates Metro cities like Delhi NCR, Mumbai, Bengaluru, and Hyderabad generally have 20-40% higher core cutting rates than Tier-2 cities like Indore, Jaipur, or Coimbatore, largely due to labour costs and demand.
5. Machine and Bit Size Cutting through thicker or harder concrete may require a larger diamond bit or a more powerful machine, which adds to the cost.
6. Waterproofing and Finishing A proper job includes sealing the hole around the pipe with weatherproof sealant or PU foam to prevent water seepage during monsoon — this is often included, but some vendors charge it separately.
Indian City-Wise Average Core Cutting Charges (2026 Estimates)
| City | Split AC Core Cutting | Window AC Core Cutting |
|---|---|---|
| Delhi NCR | ₹500 – ₹900 | ₹1,500 – ₹2,500 |
| Mumbai | ₹600 – ₹1,000 | ₹1,600 – ₹2,700 |
| Bengaluru | ₹550 – ₹950 | ₹1,500 – ₹2,500 |
| Hyderabad | ₹450 – ₹850 | ₹1,300 – ₹2,200 |
| Chennai | ₹450 – ₹800 | ₹1,200 – ₹2,000 |
| Pune | ₹500 – ₹850 | ₹1,300 – ₹2,200 |
| Ahmedabad | ₹400 – ₹750 | ₹1,100 – ₹1,900 |
| Kolkata | ₹400 – ₹700 | ₹1,100 – ₹1,800 |
These figures are general market estimates. Core Cutting India provides customised quotes based on a free site assessment, since real costs depend on wall composition, unit placement, and site accessibility.
Why AC Company Technicians Often Outsource Core Cutting
Here's something most customers don't realise: the technician who comes to install your split or window AC from brands like LG, Voltas, Daikin, Blue Star, or Samsung is usually not equipped or trained to do proper diamond core cutting. Many still use manual hammer drilling, which:
- Takes significantly longer
- Creates rough, uneven, oversized holes
- Risks cracking tiles, false ceilings, or the wall's RCC structure
- Often results in water leakage later because the hole isn't sealed at the correct angle
This is exactly why many AC service companies and individual homeowners across India now separately hire specialised core cutting contractors for a clean, professional, and structurally safe cut — rather than leaving it to the AC installation technician alone.
Tips to Get Fair Core Cutting Charges
- Always ask for a site visit before finalising a quote — wall thickness genuinely changes the price.
- Bundle multiple ACs together if you're setting up a new home or office; most contractors reduce the per-hole rate for bulk work.
- Confirm whether sealing and waterproofing is included in the quoted price, especially before monsoon.
- Avoid the cheapest hammer-drill option — a bad cut can crack tiles or, worse, hit embedded electrical wiring or rebar, costing far more to repair later.
- Check if the vendor uses a diamond core cutting machine, not just a regular masonry drill, particularly for RCC walls in apartments and commercial buildings.
Split AC or Window AC — Which Works Out Cheaper Overall?
If you're purely comparing core cutting costs, window AC installation is costlier because of the larger opening required. However, split ACs typically have higher overall installation charges (stand fabrication, longer pipe runs, more copper piping, additional labour for outdoor unit mounting), so the total installation bill often balances out or can even favour window ACs for smaller rooms or budget setups — like in a single-room rental in Noida or a shop in a Chennai market.
For larger homes, offices, and premium interiors, split ACs remain the preferred choice despite the extra installation cost, since they offer better aesthetics, quieter operation, and more flexible unit placement.
Conclusion
Core cutting is a small but critical part of any AC installation — and skipping professional handling to save a few hundred rupees can lead to cracked walls, water leakage, or even structural issues in RCC buildings. Whether you're installing a split AC in a Gurugram apartment or a window AC in a Nagpur shop, it pays to get the cutting done by trained professionals using the right diamond core cutting equipment.
At Core Cutting India, we specialise in precise, safe, and affordable core cutting services for AC installations across residential and commercial properties. From single-hole split AC jobs to full window AC wall openings, our teams use proper diamond core drilling machines to ensure a clean cut, correct drainage slope, and complete waterproofing — the first time, right.
📧 Get a free quote today at [email protected] or visit corecuttingindia.com to book a site visit before your next AC installation.
Frequently Asked Questions
Q1. What is core cutting charge for AC installation? It's the fee charged for drilling a precise hole through a wall (using a diamond core cutting machine) to route AC pipes, wiring, and drainage between indoor and outdoor units.
Q2. How much does core cutting cost per hole in India? For a split AC, it typically ranges from ₹400 to ₹1,000 per hole depending on the city and wall type; window AC openings cost more, generally ₹1,100 to ₹2,700.
Q3. Is core cutting required for window AC? Only if there's no existing window slot. In buildings without a traditional window frame, a larger rectangular core cut is needed to fit the unit into the wall.
Q4. Which is cheaper to install — split AC or window AC? Core cutting is cheaper for split AC, but overall installation (including stand, piping, and labour) can sometimes be higher for split ACs compared to window ACs.
Q5. Can I drill an AC wall hole myself instead of hiring a core cutting service? It's not recommended, especially for RCC walls, since incorrect drilling can crack the wall, hit hidden wiring, or cause water seepage due to poor sealing and angling.
Q6. How thick a hole is needed for a split AC pipe? Usually a 2 to 3 inch diameter hole is sufficient to pass the copper pipes, drain pipe, and wiring bundle.
Q7. Does core cutting damage the wall or reduce its strength? When done professionally with a diamond core cutting machine and proper technique, damage is minimal. Poor-quality manual drilling, however, can crack tiles or weaken the wall surface.
Q8. How long does core cutting take for one AC installation? A split AC hole usually takes 15–30 minutes, while a window AC opening can take 45 minutes to 1.5 hours depending on wall thickness and accessibility.
Core Cutting India | corecuttingindia.com | [email protected]