Before anyone can design what's new, someone has to document what already exists.
If you're planning an addition, a significant remodel, or any project that involves attaching new construction to an existing structure, you're going to need drawings of the existing home before design work can start. These are called as-built drawings — and they're one of the most commonly skipped steps in a renovation project, usually because nobody told the homeowner they were needed until the designer asked for them.
What as-built drawings actually are
As-built drawings are CAD documentation of an existing structure as it was actually built — not as it was originally designed, but as it currently exists. That means someone physically measures the building: room dimensions, wall locations, window and door openings, ceiling heights, foundation type, floor-to-floor heights if there are multiple levels, and anything structurally relevant to the work being planned. Those measurements get turned into a scaled, dimensioned CAD drawing set that can be used as the starting point for design work.
Why they're necessary
A designer can't draw an addition without knowing the exact dimensions and layout of what it's attaching to. A contractor can't bid accurately without understanding the existing conditions. A building department won't approve drawings that don't show the relationship between new and existing construction. And if your contractor is making assumptions about what's behind the walls — beam locations, floor joist direction, foundation depth — those assumptions have a way of becoming expensive surprises once demo starts.
What if I have the original builder's plans?
Original plans are useful, but they're not the same as as-builts. Homes are frequently built with modifications from the original drawings — framing changes, relocated walls, different window sizes. We treat original plans as a reference, not a substitute for field measurement. The as-built set reflects what's actually there, not what was intended.
When as-built drawings are required
Any addition or remodel project that involves attaching to or modifying an existing structure will need them — either as a standalone first step or as part of a full design engagement. If you're doing a simple cosmetic remodel with no structural changes, you may not need a formal as-built set. If you're adding square footage, moving load-bearing elements, or doing anything that requires a permit showing the existing conditions, you do.
How the process works
We schedule a site visit, take detailed measurements of the relevant portions of the structure, photograph key conditions, and produce a CAD drawing set from those measurements. Turnaround depends on the complexity of the structure and the scope of what needs to be documented. The as-built set then becomes the foundation for the design drawings that follow.
If you're planning an addition or remodel and aren't sure whether you need as-built documentation, reach out — we'll tell you honestly based on your specific project.