Fixed roll width
Carpet is cut from a roll of set width, so if a room is wider than the roll we need a seam or an extra piece.
Quantity and waste calculator
Carpet Quantity and Waste in Riyadh — an Area Calculator and a Guide to Cutting Waste
The most common mistake when ordering carpet yourself is using only the room area, then finding at fitting time that the quantity falls short or the surplus is huge. The reason is waste: cutting at corners, doors and seams and matching patterns. This page has a simple calculator that gives the area with a waste allowance, an explanation of what raises waste, and then we measure your space precisely during a free visit in Riyadh.
Exact measuringWe measure before settling the quantity
Free visitWe measure rooms, doors and corners
Right quantityWe work out waste for each space
Supply & fitOne team for everything
Daily7 AM to 10 PM
Why waste
Why is room area alone not enough?
Carpet comes in rolls of a fixed width, so the exact area cannot always be bought.
Corners and columns
Columns, projections and irregular corners need cuts that leave small offcuts that cannot be used.
Pattern matching
Repeating patterns need alignment between pieces, so the quantity needed is more than for a plain carpet.
Pile direction
The pile direction must be the same in all pieces or colour differences show at the seams.
Doors and built-in wardrobes
Doorways and fitted wardrobes add small areas not counted in the main room measurement.
A safety margin
A small spare piece is useful later for repairs if one spot is damaged.
How to calculate
How to calculate carpet quantity step by step
The first step is the area of each room: length × width = area in square metres. For example, a room 5 metres long and 4 metres wide is 20 square metres.
The second step is adding a waste allowance. A simple rectangular room with a plain carpet may need little waste, while a room with many corners or a repeating pattern needs more. For example, 20 square metres with 10% waste becomes about 22 square metres.
The third step is checking the roll width: it can be better to divide the area into long pieces rather than many short ones, and we work this out with you on site because it affects the number of seams and the price.
For more on measuring see our flooring measuring guide, and for the difference between roll carpet and tiles see roll carpet and carpet tiles.
Calculate the area
Estimate the carpet quantity with waste
Enter the length and width of the room, choose a suitable waste allowance (length × width = area) and send the result on WhatsApp so we can prepare a quote after the visit.
0Area (m²)
0Suggested order (m²)
Waste allowances
Which waste allowance suits your room?
These are guideline figures we use as a starting point, and we fix the exact allowance after measuring the space.
| Room shape | Pattern | Approximate allowance | |
|---|---|---|---|
| Simple rectangular room | Plain | About 5% | |
| Room with one door and a wardrobe | Plain or light | About 10% | |
| Living room with corners or columns | Plain | About 10 to 15% | |
| Rectangular room | Repeating pattern | About 10 to 15% | |
| Long corridors and runs | Plain | Depends on roll width and corridor length | |
| Irregularly shaped spaces | Any | Set after the visit |
Influencing factors
Factors that change the real quantity
Knowing these reduces surprises at fitting time.
Laying direction
It may be better to run the carpet lengthways or widthways depending on roll width and seam position.
Seam position
We prefer seams away from main walkways and strong direct light.
Stairs and thresholds
Stair pieces are counted separately because each step usually needs at least two pieces.
Skirting and edges
Skirting thickness and edge profiles can slightly change the cut at the perimeter.
Underlay
A carpet underlay is needed over the same area as the floor.
Spare stock
We leave a small spare piece where possible to replace any part that is damaged later.
Measuring steps
How do we measure your space before fixing the quantity?
A simple sketch
We sketch the rooms and note dimensions and the position of doors and columns.
Measuring lengths
We measure length and width at more than one point because walls are not always parallel.
Fixing the seams
We decide the seam positions to suit the roll width and pile direction.
Working out waste
We calculate the real allowance from the plan instead of using a generic percentage.
Confirming the quantity
We send you the final quantity with the quote to check before you order.
Special cases
Stairs, winding rooms and long runs
Stairs need a different calculation: each step is covered by a piece for the tread and a piece for the riser, and cutting rises on curved steps. That is why we do not rely on an area calculator for stairs but measure them step by step. See stair carpet.
Winding rooms and long runs such as corridors are calculated by roll width and run length to reduce seams.
- Measure every step with its real dimensions
- Treat curved or winding steps separately
- Calculate long corridors by roll width
- Review door positions and thresholds
- Avoid a seam in the middle of a doorway
Worked examples
Examples that illustrate the idea
Rounded figures for illustration only; the real quantity is set after measuring.
A 4×3 m room with a plain pattern
The area is 12 square metres, and with 5% waste it becomes about 12.6 square metres.
A 5×4 m room with a door and wardrobe
The area is 20 square metres, and with 10% waste it becomes about 22 square metres.
A 6×5 m living room with a column
The area is 30 square metres, and with roughly 12% waste it becomes about 33.6 square metres.
A 4×4 m room with a repeating pattern
The area is 16 square metres, and with 15% waste it becomes about 18.4 square metres.
An 8×1.5 m corridor
The area is 12 square metres but the calculation depends on roll width and length, and waste may be lower.
A 7×6 m office
The area is 42 square metres, and we review seams and direction with you to cut waste before fixing the quantity.
Common mistakes
Mistakes in working out the quantity
Using only the area
This often leads to a shortage after cutting and seaming.
One waste allowance for every room
Rooms differ in shape and pattern, so their allowances differ.
Ignoring pile direction
Changing direction between two pieces shows as a colour difference.
Ordering before the final measurement
Dimensions can change after skirting or doors are fitted.
Ordering tips
How to order an accurate quantity of carpet
Before asking for a quote, write each room’s dimensions on a sheet, mark door and column positions and take photos if you can. This helps us give a quantity close to reality before the visit.
If you plan different patterns or colours in several rooms, say so, so that we calculate each type separately and reduce surplus. Read our carpet fibre guide to settle the material before the quantity.
For preparation before fitting see floor preparation and levelling, which affects the final measurement.
We serve Riyadh only and every visit is free with no obligation.
After fitting
What do you do with the leftover and spare piece?
A small piece stored well helps for years.
Keep the spare piece
It is useful for patching a stain or a spot damaged by furniture.
Store it rolled
Keep it rolled in a dry place away from sun and moisture.
Note the model name
Record the type, colour and fitting date to make any future order easier.
Do not lay it on damp surfaces
Moisture can affect the backing.
Use it in wear spots
A small piece can be used at an entrance, for example.
Ask before patching
We guide you on the best way to patch so the difference does not show.
Questions about calculating carpet quantity in Riyadh
How do I calculate the carpet for a room?
Multiply length by width to get the area in square metres, then add a waste allowance suited to the room shape and pattern. Use the calculator above as a starting point and we confirm the quantity after measuring.
What is the usual waste allowance?
It varies by case, usually lower in simple rectangular rooms and higher with corners and repeating patterns. We set the real allowance after the visit.
Why does waste differ from room to room?
Because shape, number of doors and columns, pattern type and roll width differ. A regular room needs less waste than one with many corners.
Does the calculation depend on roll width?
Yes, because cutting is done from a roll of set width. Sometimes changing the laying direction reduces seams and waste.
Do I calculate stairs the same way?
No, stairs are calculated step by step because each step needs pieces for the tread and riser. We measure them during the visit.
Should I buy extra as a reserve?
A small spare piece is useful for repairing a damaged spot, but a big surplus is unnecessary. We discuss it with you in the quote.
Do you measure for free?
Yes, the visit and measuring are free inside Riyadh with no obligation to buy.
Is the calculator exact?
It is an initial estimate of area with waste, and the final quantity is fixed after actual measurement and reviewing the plan.
Start with a free visit and measuring
Send the room dimensions and a photo of the space and we will arrange the visit and quote inside Riyadh.
More guides and services you may need
How to measure your floor
A detailed guide to measuring in square metres.
Flooring installation time
How long each type takes by area.
Old carpet removal
Preparing the floor before the new one.
Carpet installation
From preparation to handover.
Carpet price factors
What really changes the price.
Flooring for small rooms
Ideas that cut waste and open the space.