The deck cover sizing tool that does the dead-load math FIRST. 6 cover types compete head-to-head: open pergola, louvered pergola (Struxure/Equinox premium), retractable awning, full gable roof, lean-to / shed cover, polycarbonate patio cover. The killer feature is the dead-load check vs the existing deck framing capacity — if you add an 11 psf gable cover with shingles to a deck designed for 10 psf dead load, the calculator flags FAIL before you commit. 5 materials × 6 roof panels × snow load × wind uplift × dead-load compatibility. 2026-Q1 retail.
Open pergola (rafters only) adds 672 lb cover dead load + 0 lb panel dead load to the deck below. Within the 10 psf design dead-load budget.
Materials $4,804 + labor $2,688. 192 sqft @ ~$40/sqft installed. Aluminum (powder-coated) cost mult 1.00× + Open air (no panels).
Use the Deck Load Calculator to check whether your existing framing can support the cover. Most older decks (10 psf default) can only handle open pergola; gable covers usually need framing reinforcement.
2026-Q1 retail pricing for aluminum + wood + composite cover materials, Struxure / Equinox / Renson louvered pergolas, generic gable + lean-to construction. Not a substitute for stamped structural engineer letter on gable or lean-to covers, or any cover where dead-load check flags amber/red.
How to use
Deck length × width. Cover length × width (usually equal to deck or smaller). Cover area drives material cost AND dead-load impact on the deck below.
Open pergola ($22/sqft material, 3.5 psf dead — no rain protection). Louvered pergola ($85/sqft, 6.5 psf — full rain protection when louvers closed). Retractable awning ($18/sqft, 1.5 psf — house-mounted, no deck structure). Gable roof ($45/sqft, 11 psf — heaviest, full pitched roof). Lean-to cover ($32/sqft, 8 psf — single-slope from house). Polycarbonate patio cover ($28/sqft, 4 psf — translucent).
Aluminum (baseline 1.0× cost, 30-yr lifespan, no maintenance). PT wood (0.60× — cheapest, but 18-yr life + annual stain). Cedar (1.40× — warm look, 25-yr, oil annually). Vinyl PVC (1.20× — covered structural only, zero maintenance). Steel (1.50× — for long spans, 40-yr).
Open air (pergola classic, no panel — light + air pass). Shade cloth ($3.50/sqft, fabric, 70-95% sun block). Acrylic ($8.20, clear/tinted, lets in light). Polycarbonate ($6.80, twin-wall, UV-stable 15-25 yr). Metal pan ($9.50, premium gable). Shingles on decking ($5.20, matches house, heaviest at 7.5 psf).
Your existing deck framing has a finite dead-load budget. IRC default is 10 psf dead. If your deck was engineered higher (some builders go 15-20 psf), enter that. If your deck is older + unknown, conservatively use 10 psf. The calculator checks whether the cover's dead load fits within this budget.
Snow load (from Snow Load Calculator) adds to the cover's roof if it catches snow (everything except open pergola + retractable awning). Wind speed Vult — coastal Gulf 130 mph, hurricane zone 160+ mph — affects wind-uplift on lightweight covers.
Top of results shows total cost range + cost per sqft + dead-load impact on the deck below. Flags: dead-load overbudget (FAIL — deck can't handle the cover), dead-load tight (warning — under 20% margin), snow-on-cover concern (heavy snow + roofed cover = engineering review), wind-uplift concern (light cover in hurricane zone), structural engineer required (gable roof + over-spec dead load).
Material guide
Three honest paths. Composite wins the 25-year math for most homeowners, wood wins on upfront cost, and PVC is unbeatable around water. Each card below answers in one glance — recalculate the bill of materials by clicking a brand in the picker above.
How we calculate
The Deck Cover/Roof Calculator sizes the 6 most common cover types over an existing deck — open pergola, louvered pergola (Struxure/Equinox $$$), retractable awning, full gable roof, lean-to/shed cover, and polycarbonate patio cover. The killer feature is the dead-load check vs the existing deck framing capacity: if you add an 8 psf gable cover to a deck designed for 10 psf dead load, you've used 80% of the deck's dead-load budget on the cover alone. Plus wind-uplift advisory for hurricane zones and snow-on-cover load math for cold regions. 5 materials (aluminum, PT wood, cedar, vinyl, steel) × 6 roof panel options (open-air, shade cloth, acrylic, polycarbonate, metal pan, shingles on decking). 2026-Q1 retail.
Cover pricing reflects 2026-Q1 national-median retail for aluminum + wood pergolas, Struxure / Equinox / Renson louvered pergola brands (premium $70-120/sqft installed), generic gable + lean-to construction, polycarbonate patio cover kits (Suncast / Palram / Aleko). Material cost multipliers from contractor surveys. Dead-load values from manufacturer cut-sheets + verified field installations. Snow + wind loads per ASCE 7-22.
Cover dead load is concentrated on the cover footprint but distributes to the entire deck framing. A 200 sqft gable cover (11 + 7.5 = 18.5 psf cover load) on a 200 sqft deck adds 18.5 psf. On a 400 sqft deck, only 9.25 psf added.
IRC default deck dead capacity is 10 psf. Open pergola = 3.5 psf (66% headroom). Gable + shingles = 18.5 psf (FAIL on 10 psf deck). Louvered pergola alone = 6.5 psf (35% headroom).
Cover types with solid roofs (louvered closed, gable, lean-to, polycarbonate) catch snow load and transfer to the cover structure. Open pergola + retractable awning don't catch snow. Above 30 psf snow zone + solid cover = structural engineering review.
Material baseline × material cost multiplier (aluminum 1.0×, wood 0.6×, cedar 1.4×) + post cost × count + optional screens + optional lighting + labor. Labor scales with cover type complexity + region.
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