Skirting and Trim Length Calculator
Total measured skirting or trim runs, add only your explicit extra allowance, and estimate minimum linear coverage from your chosen stock length or pack.
How the estimate works
L = the shared net measured length in metres. Extra E = L × explicitly supplied allowancePercent / 100 (otherwise E = 0). Adjusted length A = L + E. For individual pieces, coverage C = stockLengthM; for a pack, C = stockLengthM × piecesPerPack. Minimum purchase units N = ceil(A / C); nominal purchased length = N × C; coverage-based excess = max(0, N × C − A). Preserve full precision until the final whole-unit count; shared wholeUnits normalises floating-point noise within four scaled machine epsilons of an integer.
Linear quantity only, for one already-chosen compatible skirting or trim product at a time. Shared lengthM already excludes only supplied widths on the same run: never deduct those again. Wall windows above the skirting do not interrupt it and must not be deducted. Counts are minimum aggregate linear coverage, not a cutting, mitre, joint or ordering plan; no assumed offcut reuse, fixings, adhesives, profile suitability, price, stock availability, installation, engineering or permission guarantees. No Materials List is produced.
Worked example
Measure named runs that total 12 m after genuine same-run interruptions. With your explicitly chosen 5% allowance, adjusted length is 12.6 m. If you separately choose 2.4 m individual stock lengths, minimum aggregate coverage is 6 lengths, totalling 14.4 m, with 1.8 m coverage-based excess. This does not say those six pieces can be cut to fit every run. One actual stock-length example is Wickes product 288077, Pencil Round White Fully Finished MDF Skirting, 14.5 × 94 × 2400 mm, Pack Quantity 1 (checked 10 November 2026): its stated stock length is 2.4 m. This example is not prefilled, a suitability recommendation or an availability/price promise.
What to measure and check
Name and measure each run that actually receives this skirting or trim, or enter a reliable known total length. Use shared same-run width exclusions only where that run truly has no trim, such as a doorway without skirting; do not subtract wall windows from floor-level skirting. If your runs are already measured between interruptions, do not exclude them again. Then optionally enter your own allowance and the facts for an already-chosen stock length or equal-length pack. Use separate calculations for different products or mixed stock lengths.
How should I measure the skirting length?
Use named runs at skirting level, or a reliable known total. The shared measurement entry totals the runs and subtracts only explicitly supplied widths belonging to the same run. This tool uses that net length once; it does not reconstruct room perimeter or subtract openings again.
Should I subtract windows?
Do not deduct wall windows above floor-level skirting. A doorway or other genuine interruption may be excluded only from the specific run that has no skirting there. For a different trim position, measure where that trim actually goes rather than applying floor-level skirting assumptions.
Is a waste percentage included?
No numeric allowance is assumed. A blank allowance adds no extra. An explicitly entered allowance is shown separately from the measured and adjusted lengths; it does not guarantee sufficient material.
Can it calculate a pack count?
Yes, if you choose pack mode and supply both the length of each piece and the positive whole number of equal-length pieces in the pack. Missing facts leave length results visible without guessing counts. Mixed-length packs are outside this method.
Will the calculated stock lengths fit all my runs?
Not necessarily. The count rounds up the total linear requirement divided by nominal purchase-unit length. It does not allocate runs, assess maximum uninterrupted lengths, plan cuts or mitres, allow for saw kerf or defects, or assume offcuts can be reused. Check the actual run-by-run cutting requirement separately.
Are fixings, adhesives or installation specifications included?
No. Only linear length and optional aggregate stock coverage are estimated. Profile choice, fixings, adhesives, installation, structural design, permissions and compliance are not calculated, and no Materials List is produced.
Can I combine different rooms or products?
The shared entry can total named runs from several rooms if they use the same already-chosen product and stock facts. Keep different profiles, stock lengths or mixed-length packs in separate calculations. Aggregating length does not create a cross-room cutting plan.
Where the numbers come from
Formula version v1.0. Implemented and tested 10 November 2026. Product-dependent figures remain your supplied facts; a cited example is not a selected product or a universal yield.