DeckMath
5 paint types · 5 conditions · paint-vs-stain TCO · DIY + contractor

Deck Paint Calculator

Compute exact gallons of paint, primer, and supplies plus total installed cost for painting a deck. 5 deck-paint product types — 100% acrylic porch & floor (Behr Premium, Sherwin Williams Porch & Floor, 7-yr lifespan), oil-modified alkyd (Benjamin Moore INSL-X Tough Shield, 8-yr lifespan), elastomeric coating (Rust-Oleum RockSolid, Behr DeckOver Max, 10-yr lifespan, 30% more material), solid-color stain (Olympic Maximum Solid, Cabot Solid Acrylic, 6-yr lifespan), and anti-slip textured (Sherwin Williams DeckShield with sand-grit additive, 8-yr lifespan for wet-zone walkways). Coverage formula accounts for first-coat penalty on rough/weathered/previously-stained wood (15-30% coverage reduction). Surface scope: deck-only, deck + rails + stairs, or deck + rails + stairs + skirting. 5 condition tiers drive prep cost. Includes paint-vs-stain 5-yr TCO comparison and a side-by-side ranking of all 5 paint-type options at the same scope.

Start calculating
Get 2–3 free quotes
5 paint productsPaint-vs-stain TCOPrimer math includedCondition-based coverage3 color tiersFree forever
5 products·Acrylic / oil / elastomeric / solid / anti-slip
$0.55-3.85/sqft·DIY material → contractor range
7-10 yr·Lifespan range
5-yr TCO·Paint vs 3 stain tiers

Inputs

Deck size + scope

sqft

ft

ea

ea

sqft

Total paint area725 sqft

Recoat existing paint. Scrape peeling spots + spot-prime + light sand. No full primer needed. Best-coverage scenario.

Install + region

Northeast · 1.22× labor

100% acrylic porch & floor

725 sqft · 2 coats · previously-painted · contractor · PA

Project total
$4,053 $5,094
$7/sqft · 8% contingency included · 7-yr lifespan
Northeast 1.22×8 gal + 3 gal primer

Gallons needed

First coat
4.5 gal
Coverage 161 sqft/gal
Recoats × 1
3.5 gal
240 sqft/gal each
Primer required: 3 gal @ $38/gal$114

Cost breakdown

Paint (8 gal × $52/gal)$416
Primer (3 gal)$114
Supplies (brush/roller/tray)$65
Prep (previously-painted)$471
Labor (Northeast 1.22×)$3,319
Subtotal (high)$4,717
Project total (high, +8% contingency)$5,094

5-year TCO: paint vs stain

Acrylic P&F paintCURRENT$4,574 · 7yr · 1× in 5yr
Transparent stain$2,166 · 2.5yr · 2× in 5yr
Semi-transparent stain$5,562 · 4yr · 2× in 5yr
Solid color stain$3,267 · 6yr · 1× in 5yr

Paint typically wins TCO on full deck + rails + skirting scope (vertical surfaces hold paint better). Stain wins on horizontal deck-only scope (penetrates instead of films). Numbers assume professional labor at current region.

Paint-type comparison (same scope)

Solid stainCHEAPEST$4,548 · $6.3/sqft
Acrylic P&FPICKED$5,094 · $7/sqft
Oil-alkyd$5,588 · $7.7/sqft
Anti-slip$7,188 · $9.9/sqft
Elastomeric$8,977 · $12.4/sqft

Recommendations

  • Acrylic P&F requires primer on previously painted (recoat scenario). Skipping primer compromises adhesion; recommend toggling primer on (adds ~$114 for ~3 gal).
  • Solid color stain (paint-like finish) is cheaper by $546 at this scope. Trade-off: 6-yr vs 7-yr lifespan, $48/gal vs $52/gal product cost.

Code + product references

  • EPA 40 CFR Part 745 — Lead-paint testing required before sanding/scraping pre-1978 painted surfaces
  • MPI 60 — Master Painters Institute deck-paint product spec (industry coverage standard)
  • ASTM D2486 — Scrub resistance test (verify paint rating)
  • Manufacturer specs — apply at 50-90°F surface temp, < 85% RH, no rain forecast 24 hr

How to use

How to use the deck paint calculator in 5 steps.

  1. 1

    Enter deck sqft + surface scope

    Deck footprint sqft (top surface). Then choose scope: deck-only, deck + rails + stairs (adds railing LF × 7.5 sqft conversion + stair treads × 4.5 sqft + stringers), or deck + rails + stairs + skirting (adds vertical skirting sqft). Most deck-paint projects include the rails and stairs since paint exposed there ages faster than the deck surface.

  2. 2

    Pick wood condition tier

    5 tiers drive prep cost + coverage penalty. New PT MUST weather 6+ months first. Weathered gray = 1+ yr old PT, 15% coverage penalty. Previously stained = must strip or sand to bare wood. Previously painted = recoat scenario (best coverage, lowest prep). Rough mill = 30% coverage penalty (paint fills grain). Wrong condition selection causes paint failure within 1-3 yrs.

  3. 3

    Pick paint type + coats + color tier

    5 paint product types with documented coverage + lifespan + price. Coats: 1 (touch-up only), 2 (default for new paint), 3 (rough wood or color change). Color tier: standard (basic colors), premium (+18%), custom-match (+35%). Premium colors often cost more from the manufacturer + require minimum-order batches.

  4. 4

    Primer toggle + installer mode

    Primer required on bare wood for most paint types (auto-toggled on by condition). Skip primer ONLY on recoat-existing-paint scenarios with same paint type. Installer mode: DIY (hides labor, shows hours estimate + opportunity cost at $35/hr), or contractor (full labor billed by regional multiplier).

  5. 5

    Read paint vs stain comparison

    5-yr TCO panel surfaces paint vs 3 stain alternatives (transparent / semi-transparent / solid) at same scope. Paint lifespan 7-10 yrs (1 recoat in 5 yrs). Stain lifespan 2-6 yrs (2-3 recoats in 5 yrs). Paint typically wins 5-yr TCO when scope is rails + stairs + skirting because vertical surfaces hold paint better than stain.

How we calculate

How DeckMath calculates this — IRC 2021 sources.

The Deck Paint Calculator computes gallons of paint, primer, and supplies plus total installed cost (DIY or contractor) for painting a deck. 5 deck-paint product types — 100% acrylic porch & floor (Behr Premium, Sherwin Williams Porch & Floor, 7-yr lifespan), oil-modified alkyd (Benjamin Moore INSL-X Tough Shield, 8-yr lifespan), elastomeric coating (Rust-Oleum RockSolid, Behr DeckOver Max, 10-yr lifespan, 30% more material), solid-color stain (Olympic Maximum Solid, Cabot Solid Acrylic, 6-yr lifespan), and anti-slip textured (Sherwin Williams DeckShield with sand-grit additive, 8-yr lifespan for wet-zone walkways). Coverage formula accounts for first-coat penalty on rough/weathered/previously-stained wood (15-30% coverage reduction). Surface scope: deck-only, deck + rails + stairs, or deck + rails + stairs + skirting. 5 condition tiers drive prep cost (power wash + sand + scrape + spot prime). Includes paint-vs-stain 5-yr TCO comparison and a side-by-side ranking of all 5 paint-type options at the same scope.

IRC references

  • EPA 40 CFR Part 745 — Lead-paint testing required before sanding/scraping pre-1978 painted surfaces
  • MPI 60 — Master Painters Institute deck-paint product spec (industry coverage standard)
  • ASTM D2486 — Scrub resistance test (verify paint rating)
  • Manufacturer specs — apply at 50-90°F surface temp, < 85% RH, no rain forecast 24 hr

2026-Q1 retail pricing — Home Depot / Lowe's / Sherwin Williams / Benjamin Moore / Behr. Acrylic P&F $52/gal. Oil-alkyd $65/gal. Elastomeric $78/gal. Solid stain $48/gal. Anti-slip textured $72/gal. Primer $38/gal at 250 sqft/gal. Coverage 75-200 sqft/gal first coat (× 1.30 on recoat). Pro labor $1.95-3.85/sqft. Regional multiplier (NE 1.22× / W 1.28× / S 0.92× / MW 1.00×). 8% contingency.

Gallons needed
firstCoatGallons = ceil(totalSqft / (coverage_first × condition_mult), 0.5); recoatGallons = ceil((totalSqft / coverage_recoat) × additional_coats, 0.5); totalGallons = first + recoat

First-coat coverage varies by paint type (75-200 sqft/gal): elastomeric 75 sqft/gal (thick), acrylic P&F 180, solid stain 200. Recoat coverage is 25-35% better (~240-270 sqft/gal). Condition multiplier reduces first-coat coverage: new PT 0.95×, weathered 0.85×, previously stained 0.90×, recoat 1.00×, rough mill 0.70×. Round UP to 0.5 gal — paint stores sell in 1, 2.5, 5 gal — odd-coverage purchases waste material.

Total surface area
totalSqft = deckSqft + (rails_LF × 7.5 + treads × 4.5 + sections × 12) [if scope includes] + skirting_sqft [if scope includes]

Railing LF × 7.5 sqft assumes 36″ tall guard with balusters painted both sides. Stair tread 1.5 ft × 3 ft = 4.5 sqft each. Stair section accounts for visible stringer + skirting at ~12 sqft per section. Skirting sqft entered separately (varies by deck height and scope). Total drives gallon math.

Prep cost
prepCost = totalSqft × prep_$/sqft (varies by condition tier)

Condition tier sets $/sqft for prep: new PT $0.35, weathered $0.55, previously stained $0.85 (strip required), previously painted $0.65 (scrape peeling spots + spot prime), rough mill $0.45. Prep includes power wash + sand + scrape + spot prime. Skipping prep is the #1 cause of paint failure within 18 months.

Labor (contractor)
labor = (paint_$/sqft + prep_$/sqft × 0.30) × totalSqft × coat_mult × region_mult

Paint $/sqft varies $1.95 (solid stain) to $3.85 (elastomeric — heavy material). Coat multiplier 1 + 0.60 per additional coat (recoats are faster than first). Region multiplier (NE 1.22× / W 1.28× / S 0.92× / MW 1.00×). Prep included at 30% of prep cost as labor share (rest is materials/disposal). 8% contingency on subtotal.

5-year TCO (paint vs stain)
tco_5yr = singleCycleCost × ceil(5 / lifespanYears)

Paint lifespan 7-10 yrs = 1 application per 5-yr horizon. Stain transparent 2.5 yr = 2 applications. Semi-transparent 4 yr = 2. Solid stain 6 yr = 1. Paint typically beats stain on 5-yr TCO for rails + stairs (vertical surfaces hold paint better). Stain wins on horizontal deck-only scope (penetrates instead of films).

Save your plan

Don’t lose this estimate.

Your inputs are preserved in the URL — email it to yourself or copy the link so you can compare with contractor bids later. No account needed.

Get matched

Want 2–3 free quotes for this exact deck?

We'll send your plan to vetted local builders. Free, no obligation.

People also ask

Deck paint questions, answered.

  • Coverage varies by paint type: 100% acrylic porch & floor covers ~180 sqft/gal first coat / 240 sqft/gal recoat. Oil-alkyd similar. Elastomeric coating much less — 75 sqft/gal first coat (heavy material). Solid stain best coverage at 200/270. For a 320 sqft deck with rails + 1 stair section (totaling ~720 sqft including railing equivalent), 2 coats of acrylic P&F needs ~3.5 gal first coat + ~3 gal recoat = ~6.5 gal total. Always round up to nearest standard can size (1 / 2.5 / 5 gal).

  • Paint lasts 7-10 yrs but peels if applied wrong; requires strip & sand to recoat. Stain lasts 2-6 yrs depending on opacity; recoats over old stain without strip. Paint wins on TCO when deck includes rails + skirting (vertical surfaces hold paint, stain weathers fast there). Stain wins on horizontal deck-only (penetrates and weathers gracefully). On a 5-yr horizon: paint typically costs ~$3,200 for full scope vs solid stain ~$2,400 — but paint looks better and resists scuffs. The 5-yr TCO panel runs the math for your scope.

  • Yes, but only AFTER weathering 6+ months. New PT has moisture content > 25% and treatment chemicals on the surface that prevent paint adhesion. Paint applied too soon peels in 6-12 months. Verify with a moisture meter (probe to ¼″ depth) — must read < 15% before painting. Best practice: install in fall, let weather all winter, paint following spring. Cedar and untreated wood can be painted immediately after install (no chemical leach period).

  • Yes, on bare wood (new PT, weathered, rough mill) AND when paint type requires it (acrylic P&F, elastomeric, anti-slip textured). Solid color stain and oil-alkyd are self-priming on most surfaces. Primer adds ~$50-90 (1-2 gal at $38/gal + coverage 250 sqft/gal) and is the difference between 7-yr paint life and 18-month peel. Spot-prime exposed wood on recoat scenarios where some old paint has peeled. Primer choice: bonding primer for slick surfaces, stain-blocking primer for tannin-bleeding woods (cedar, redwood).

  • Acrylic porch & floor: 7 yrs. Oil-modified alkyd: 8 yrs. Elastomeric: 10 yrs. Solid color stain: 6 yrs. Anti-slip textured: 8 yrs. Lifespan assumes proper prep + primer + 2 coats applied within manufacturer temp/humidity window. Cut these numbers in HALF if applied wrong (e.g., no primer over stain, applied to wet wood, applied below 50°F). Lifespan is measured to first major recoat — minor touch-ups required at year 3-4 on high-traffic decks.

  • Generally NO — paint will peel within 18-36 months over stain. The exceptions: (1) elastomeric coatings can be applied over sound stain after spot-priming any glossy areas, (2) some manufacturers explicitly list 'paintable over solid stain' on label. Best practice: strip old stain to bare wood with chemical stripper or sand to 80-grit, then prime + paint. The Resurfacing Cost Calculator on this site has a more detailed cost breakdown if you're going through major surface changes.

  • For most homeowners: 100% acrylic porch & floor (Behr Premium Porch & Floor, Sherwin Williams Porch & Floor). 7-yr lifespan, water cleanup, low-VOC, $50-55/gal. For maximum durability: oil-modified alkyd (Benjamin Moore INSL-X Tough Shield, Cabot Solid Acrylic-Alkyd) at $60-70/gal, 8-yr lifespan, slightly tougher film. For decks with hairline cracks: elastomeric (Rust-Oleum RockSolid, Behr DeckOver Max). For pool decks or wet zones: anti-slip textured. Don't use exterior siding paint — it's not formulated for foot traffic.

  • DIY material-only: $0.55-0.95/sqft including paint + primer + supplies. Contractor installed: $2.25-3.85/sqft for prep + paint (2 coats) + cleanup. A 320 sqft deck with rails: DIY $385-660 / contractor $1,580-2,700. Elastomeric coatings cost 30-50% more (heavy material). Pre-1978 home demands lead testing first ($165). Custom-color match adds 35% to paint cost. Add 8% contingency for spills + extra coats on rough patches.

  • Minimum 2 coats for new applications. 3 coats for: rough mill lumber, color changes (light over dark), high-traffic decks. 1 coat only for: touch-ups within 2 yrs of original application using same paint. The first coat seals + colors, the second coat builds durability film thickness. Recoat window varies 4-24 hr by product — always read product label. Most acrylics: recoat after 4 hours. Oil-alkyd: 8-24 hours. Elastomeric: 24-48 hours.

  • Most deck paints require 50-90°F surface temp during application AND for the curing window (typically 24-48 hrs). Below 50°F, paint cures too slowly and may crack or peel. Above 90°F, paint dries too fast and shows brush marks. Newer 'low-temp' formulas (e.g., Sherwin Williams Loxon XP) work down to 35°F. Always check the product label. Best painting windows: spring/fall, dry weather, no morning dew on surface, no rain forecast for 24-48 hr.

Embed this calculator

One line. Any site. Free.

Drop the snippet into your contractor site, blog, or marketing page. Theme matches the parent site automatically.

<!-- Deck Paint Calculator — free embed by DeckMath -->
<a href="https://deckmath.com/calculators/deck-paint-calculator"
   data-deckmath-calc="deck-paint-calculator"
   data-theme="auto">Free Deck Paint Calculator by DeckMath</a>
<script src="https://embed.deckmath.com/v1.js" async></script>
One tool · free · no signup

Plan the whole project, not just one number

The Deck Project Planner turns your dimensions into a complete material list, cost, 3D preview, and a PDF you can take to the lumber yard — all in one place.