Trex Deck Designer Alternatives (Real Limits Compared)
Trex Deck Designer is a solid choice, but people look for alternatives because of the fine print: Completely free with no payment and no export paywall, but every board, railing and SKU it prices is a Trex composite product, so the shopping list only works if you actually buy Trex. On top of that, locked entirely to the Trex product catalog. Strong options to compare include TimberTech / AZEK Deck Designer, Decks.com Deck Designer, and Fiberon Discovery Deck Designer. Below we line up the real free limits of each — what it exports, what it watermarks, and which platforms it runs on — so you switch for the right reason.
Alternatives at a glance

TimberTech / AZEK Deck Designer
Free, brand-lockedFree to design, save, compare and download a materials take-off, but the take-off only covers AZEK/TimberTech parts and starting a project signs you up for dealer and contractor outreach.

Decks.com Deck Designer
Free, with limitsFree to design and download plans plus a suggested material list after a free signup, but you cannot change the framing lumber sizes and the materials are a suggested list, not a guaranteed takeoff.

Fiberon Discovery Deck Designer
Free, brand-lockedFree with unlimited designs and a downloadable bill of materials, but the BoM is explicitly an estimate and every component is a Fiberon product.
Switch to one of these if…
Each card leads with its pricing and free-tier reality — pick the one whose limits you can live with.

TimberTech / AZEK Deck Designer
Free, brand-lockedFree to design, save, compare and download a materials take-off, but the take-off only covers AZEK/TimberTech parts and starting a project signs you up for dealer and contractor outreach.

Decks.com Deck Designer
Free, with limitsFree to design and download plans plus a suggested material list after a free signup, but you cannot change the framing lumber sizes and the materials are a suggested list, not a guaranteed takeoff.

Fiberon Discovery Deck Designer
Free, brand-lockedFree with unlimited designs and a downloadable bill of materials, but the BoM is explicitly an estimate and every component is a Fiberon product.