Powered by Oasis EngineeringModular Foundation Certifications
Licensed Professional Engineers
39 states
39 states
Powered by Oasis EngineeringModular Foundation Certifications
How a remote foundation certification actually works — the standard we certify against, the evidence protocol behind every case, and the quality controls that decide whether a letter is issued.
A factory-built modular unit has no single federal guide the way a HUD-code manufactured home has the PFGMH. It is approved sheet by sheet: a state industrialized-building program approves the unit, and the local authority having jurisdiction approves the foundation and the installation. So the standard we certify against is the approved plan set for your installation, together with the manufacturer’s published installation manual. The manufacturer says the same thing, in red, four separate times: “in the event of any discrepancies… the approved drawings shall control in all aspects.”
That is why we cannot issue a letter without the approved plan set. It is not paperwork — it is the yardstick. Where the manufacturer’s drawings give measurable requirements, we check them: the bearing surface flat and level to within an eighth of an inch between any two points around the perimeter, the perimeter and diagonal plan dimensions, the anchor-plate layout for the roof condition actually installed, the central bearing point and its shim stack, and the base envelope the installation manual calls out step by step.
Where a lender evaluates affixture against HUD’s Permanent Foundations Guide for Manufactured Housing, we will address it — but as a recognized benchmark for permanency and nothing more. The PFGMH does not govern modular housing, and a letter implying otherwise could invite an underwriter to reclassify a modular unit into the manufactured-home bucket, which would cost the borrower money. Precision here is the service.
Our remote evidence protocol is informed by the recommended practices published for remote inspections by the International Code Council and the National Fire Protection Association (see References). Those publications address live-video inspections by code officials; we adapted their core principles — verified location, directed capture, qualified review, documented records, and an unconditional path back to an on-site visit — into an asynchronous, evidence-preserving protocol built for foundation and installation certification.
Before the first photo, the photographer signs a recorded agreement: the photos are of the subject property, taken during this session, unaltered, and captured safely. The agreement is stored write-once with a cryptographic fingerprint (SHA-256) of the exact text signed, the signer's name, timestamp, and starting location.
The photographer doesn’t decide what to photograph — the engineer already has. Our guided app walks a checklist derived clause by clause from the manufacturer’s installation manual and the structural sheets of the approved plan set: unit identity (the build data placard with its serialized identification number, the approval agency’s insignia, the compliance certificate inside the sub-panel door), all four elevations with the ground line, the perimeter foundation edge condition, the anchor-plate run along every wall and close-ups of the hold-down hardware, the corner conditions, the central bearing point and its shim stack, the roof system that decides which anchorage sheet applies, the base envelope and skirt board, and the utility connections. Where a tape and a level are on site, we add the levelness and diagonal checks the drawings are strict about. Submission is locked until every required item is complete.
Each photo's camera timestamp and GPS coordinates are extracted and preserved before upload, with device geolocation as a fallback — so the record shows not just what was photographed, but where and when. This adapts the location-verification practices recommended for remote inspections to a per-photo, machine-verifiable form.
The engineer runs an independent back-check of every property using publicly available records: county property appraiser data, GIS parcel maps and county aerials, historical satellite and street-level imagery, online listing photos, and building-permit records where available. This cross-checks the unit’s siting, additions, and history against the submitted photos — including corroborating that the unit has not been relocated since installation, a statement every letter makes. The approved plan set and any permit or final-inspection record you upload are read alongside the photographs, not filed and forgotten.
A licensed Professional Engineer personally reviews every photo against a written triage checklist, alongside the approved plan set and the independent research above — judgment drawn from thousands of structural and property inspections across his career, in every form from crawlspaces to post-storm forensics. Nothing about this step is automated. No certification is issued until the engineer can confirm the as-built condition against the approved drawings.
If any photo is unclear or incomplete, the engineer reopens exactly those items with specific instructions — the photographer's link resumes where they left off. And the engineer retains the unconditional right to require an on-site visit, or to decline and refund, where the property cannot be responsibly certified from photographic evidence. Conditions that trigger escalation include anchorage that cannot be identified or counted from the photographs, visible settlement or undermining, standing water at the foundation, a crawl space closed off with no usable visibility of the central bearing point, and site-built structures that may share load with the unit.
The letter is reviewed, signed, and sealed by the licensed engineer, states its methodology and scope plainly, and is delivered with a durable download link. The complete case file — photos with their metadata, the signed agreement, the review history, and the sealed letter — is retained for a minimum of two years.
Remote review is a methodology choice with real advantages — the evidence is timestamped, geolocated, and permanently reviewable, which a drive-by site visit is not — and real limits, which our letters state rather than hide. Each letter classifies the observed as-built condition against the approved plan set and the manufacturer’s installation requirements; it is not a structural design, a plan review, an evaluation of remaining service life, or a verification of factory workmanship. We also state what we could not see: reinforcement, anchor embedment, footing dimensions below grade, concrete strength, compaction, and vapor-retarder continuity are concealed once a unit is set, and the letter says they were not verified rather than implying they were. If the tape and level checks weren’t taken, the letter says that too. Where photographic evidence isn’t enough to certify responsibly, we say so — and either visit the site or refund in full.
The approved plan set and permit record for the subject installation, as issued by the authority having jurisdiction.
The manufacturer’s published installation manual for the subject model — for Boxabl Casita installations, BXB-000009 Installation Manual.
ICC Evaluation Service, ESR-4725 — evaluating the structural insulated panels used in these units, not the completed unit.
U.S. Department of Housing and Urban Development, Permanent Foundations Guide for Manufactured Housing (HUD-4930.3G) — referenced as a permanency benchmark only, not as a governing standard for modular housing.
International Code Council, Recommended Practices for Remote Virtual Inspections (RVI), First Printing, May 2020.
National Fire Protection Association, Building Code Development Committee, Conducting Remote Video Inspections, August 2018.
The ICC and NFPA publications are referenced as sources that informed the design of our protocol. Manufacturer documentation is cited and summarized under its own distribution terms and is never republished. We are an independent engineering practice, not affiliated with, endorsed by, or sponsored by the ICC, the NFPA, or any manufacturer.
$495 flat · 1–2 business days after your photos are in · 100% refund if we can’t help.
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