Guide · Specifications and drawings · 07 21 13

Check insulation specifications against wall sections

A thermal value in a specification and an insulation layer in a wall section may describe different things. Establish the assembly and measurement basis before deciding that the numbers agree.

Trace each insulation designation into the wall section and specification, comparing material, thickness, location, and the basis of the stated thermal value. Check transitions and adjacent layers separately so that a matching schedule entry does not hide an unresolved junction.

Assemble the review package

Collect the wall-type schedule, envelope sections, insulation specification, and relevant energy-design inputs. Add the roof, slab-edge, opening, and parapet details needed to follow the selected assembly. This guide focuses on board and block insulation; identify separate sections for other products rather than assuming one clause covers every insulation type.

WBDG publishes UFGS 07 21 13: Board and Block Insulation as a public guide-specification reference (accessed September 16, 2026). Use your project’s issued specification and amendments for the actual comparison; the guide specification does not automatically govern your project. The checklist below is an original suggested review workflow, not a reproduction of the UFGS requirements.

Eight checks to run against the issued set

Use one record per location or system. The CSV contains the same eight prompts plus fields for source revisions, observed evidence, the review owner, the decision, and closure references.

Eight specification-to-drawing checksSwipe or scroll sideways to read all columns.
CheckSources to compareQuestion to resolve
Type-to-location mapWall tag + insulation product clausesIs each insulation material assigned to a named layer and location? Identify selections that remain as unresolved alternatives.
ThicknessAssembly dimension + product requirementsDo the specified thickness and drawn build-up describe the same layers? Record where a dimension covers the whole wall rather than the insulation alone.
Thermal-value basisWall notes + energy inputs and specificationDo values refer to the material, a thickness, or the complete assembly? Preserve units and assumptions instead of comparing unlike quantities.
ContinuityTypical section + slab-edge and opening detailsCan the insulation layer be followed through the selected junctions? Mark interruptions and ask whether they are intentional design conditions.
AttachmentSupport details + attachment clausesDoes the package identify how the insulation is retained and how attachments relate to adjacent cladding or structure?
Adjacent membranesLayer sequence + membrane requirementsAre insulation, air-control, water-control, and vapor-control layers identified separately? Flag a reversed or unexplained sequence for review.
Product suitabilityLocation and assembly references + selected product dataIs the documented product basis relevant to the actual location and assembly? Ask qualified reviewers to resolve missing suitability evidence.
Substitution impactProposed product + wall and interface detailsIf a product changes, have thickness, attachments, and dependent junctions been revisited? Treat a product name change as a possible assembly change.

Worked example: material value compared with assembly value

Illustrative example: a wall note lists a thermal target without identifying whether it describes the full assembly. The specification lists a board product and thickness, while an energy summary uses another value. The three numbers cannot be judged inconsistent until the scope and units of each are established.

Record each value exactly, including its source, and ask the envelope designer to identify the material and assembly assumptions. If the answer changes the board thickness, trace that change into the window returns and cladding attachments. Close the issue with coordinated references, rather than a note that the larger value was selected.

Avoid a false conflict

A drawn continuous line does not prove thermal performance, and matching material values do not establish compliance of the whole envelope. This review identifies document questions. Thermal calculations, condensation assessment, and assembly acceptance need their own design basis.

When requirements disagree, follow the project’s document-control and clarification process. Do not assume that drawings always override specifications, or the reverse. Identify the exact sources and request an authorized decision.

Close the issue across the affected documents

Record the location or tag, drawing and specification references, issue dates, observed difference, and the decision needed. Assign an owner and keep the item open until the response identifies the governing requirement. Check the revised drawings and specification references together; a response email alone may leave the issued package inconsistent.

For the overall process, use the guide to drawing and specification conflicts. Mark an inapplicable checklist row with a reason, and distinguish a verified correction from a question that still needs design information.

Where Groundbook fits

Groundbook’s drawing and specification review helps investigate potential disagreements in the documents you supply. Include the relevant specification sections and drawing references, then verify the cited evidence with the responsible reviewers before acting on a finding.

Questions, answered

FAQs

Is insulation R-value the same as whole-wall performance?

They describe different scopes when one refers to insulation material and the other to the complete assembly. Confirm the basis, units, and assumptions before comparing values.

Where should insulation continuity be checked?

Follow the chosen layer through slab edges, openings, roof-to-wall junctions, parapets, and other transitions actually present in the reviewed assembly.

Can a substitute insulation product affect the drawings?

Yes. A different thickness or attachment arrangement can affect adjacent details. Ask the design team to review those dependencies with the proposed product.

Bring your next set into focus

Set up a review or talk through your project with our team.