Project Planning & Design (PPD) and Project Development & Documentation (PDD) are the two longest ARE 5.0 divisions — each has 100 items — and they overlap more than any other pair. Both include codes and regulations; both are full of building systems and materials. That overlap is why many candidates take them close together, and also why questions from one can feel like questions from the other.
The clearest way to tell them apart is to follow one building through both.
The short answer
PPD asks you to choose. PDD asks you to make it work.
- In PPD you are in preliminary design: where the building goes, which structural and mechanical systems suit it, how the program, code and budget fit together. The division focuses on the preliminary design of sites and buildings.
- In PDD you are developing and documenting that design: how materials and systems integrate in assemblies and details, how the drawings and specifications describe them, and what they will cost. It covers the integration and documentation of building systems, material selection and material assemblies.
One building, two divisions
Imagine a two-story community library on a sloping suburban site.
In PPD
The questions are about options and fit:
- Where on the slope should the building sit to limit grading and keep an accessible entrance?
- Given the occupancy and size, which construction type allows the area and height the program needs?
- Should the reading room’s roof be framed with steel joists or a longer-span system, given the column-free space the client wants?
- Which HVAC approach suits the climate, the budget and the floor-to-floor height you can afford?
In PDD
The design is chosen; now it has to be built correctly:
- How does the exterior wall keep water and air out while letting moisture dry — and where do those layers continue around a window?
- Where do the ducts, sprinkler mains and light fixtures fit within the ceiling space below the joists?
- Which information belongs on the wall section, and which belongs in the specification for the air barrier?
- How has the cost estimate changed now that the envelope is fully detailed?
Where they genuinely overlap
Codes and regulations appear in both, but at different scales. PPD tends to apply code at the building level — occupancy, construction type, allowable area, egress layout. PDD applies it at the assembly level — the rating of a particular wall, how an opening is protected, the dimensions of an egress component.
Building systems appear in both, too. In PPD you select a system and understand its consequences for space, code and cost. In PDD you integrate it with everything else and document it.
Cost appears in both: PPD’s budgeting is about how design decisions drive cost; PDD’s cost estimates follow the developed documents.
Should you take them back to back?
Many candidates do, because the shared material is fresh. A common approach is to take PPD first — its system-selection thinking gives context for PDD’s details — and schedule PDD soon after. But the right order depends on your experience: someone who works mostly on construction documents may find PDD the more natural starting point.
Whichever you choose, keep one habit: when you study a topic that appears in both, write down the PPD question (which option?) and the PDD question (how is it built and documented?) side by side.
How to study the pair
- Build comparison tables for systems — structural, mechanical, envelope — with columns for when each fits, what it costs in depth or space, and code implications. That’s your PPD material.
- Read details layer by layer — water, air, vapor, thermal control — and trace each one across joints and openings. That’s your PDD material.
- Run the same small building through both whenever you can, as in the library example above.
- Finish each division with full-length timed practice and check the current ARE 5.0 Guidelines.
The PPD exam guide and the PDD exam guide cover each division’s content areas and a worked concept in more depth.