How Much Siding Do I Need?
The direct answer to the most-asked siding question — enter your walls and get squares, panels and boxes, waste included.
Walls (feet)
Gables / triangles optional
Windows & doors to subtract
Tip: measure each wall's width × height at its widest points. A per-wall audit table appears below so you can check every number.
Your siding squares, panels and cost appear here.
Estimated from wall count and perimeter — confirm against your actual corners and openings.
Cost per sq ft: – · per square: –
| Surface | Area (sq ft) |
|---|
From 'I have no idea' to a shopping list
This is the question almost everyone starts with, and the honest answer is: it depends entirely on your walls, so let's measure them. There's no reliable shortcut from square footage of floor space or a photo — you need the actual exterior wall area. The good news is that gathering it takes ten minutes and the calculator handles every conversion after that.
Work around the house, enter each wall and gable, list your openings, and you'll get a clean count of squares and boxes with a waste cushion already applied. Pick your material for the right coverage and price.
Getting an estimate in a couple of minutes
There's no learning curve here. Enter what you measured and the tool does the conversions; the only judgment call is the waste percentage. Start by choosing your material at the top of the form, since that sets the coverage the math relies on. Then add your walls one line at a time — front, back and both sides — typing each width, height and quantity.
Next, deal with the parts a plain rectangle misses: add any gable as its base and rise, and subtract each window and door by size and count. Finally, set a waste allowance (10% for a simple house, more for a cut-up one) and, if you want a budget, turn on the cost fields. The result — squares, panels, boxes, accessories and price — updates as soon as you calculate, ready to print, copy or share.
Siding calculator by material
Coverage and price change with the product. Pick the calculator tuned to what you're installing — each uses the same measuring engine with material-specific defaults.
Rules of thumb (use with care)
Single-story homes often land around 12–18 squares; two-story homes frequently 22–30. These are only sanity checks — your openings and wall heights decide the real figure, so measure before you buy.
About the accuracy of these results
We'd rather be transparent than falsely precise. The quantity math is deterministic and matches standard takeoff practice, so if your inputs are right, your squares and piece counts are right. Where real-world variation lives — coverage by profile, and installed cost by region and crew — we use typical published figures and present them as ranges. That makes this a strong planning number, not a binding quote; a contractor's field measure remains the final word.
The questions that come right after 'how much'
Knowing the quantity is the start of the conversation, not the end. These are the follow-ups almost everyone has next.
- How much extra? The 10% waste built in covers offcuts; add a spare box for future repairs on top.
- Which material? The area is fixed, but panels, boxes and price change by product — switch materials to compare.
- What will it cost? Turn on the cost inputs for an installed range alongside the quantity.
- How do I order? Take the square count to a supplier; it's the unit they quote from.
Work through those and you go from a raw quantity to a genuine plan you can act on today.
Frequently asked questions
How much siding do I need for a 2,000 square foot house?
How do I know how many boxes to buy?
Does the answer change by material?
Should I buy extra?
Notes from the field
"Went from clueless to a printed shopping list in one sitting. Bought the right amount."