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Interactive Crawlspace Trainer + FHA Foundation Certification | Oasis Engineering

Interactive 3D Trainer

Crawl Under a Manufactured Home — Without Getting Dirty

This is a first-person look at the most common manufactured home foundation in America: CMU block piers on footing pads with steel tie-down straps to ground anchors. You’re at crawl height — about 26″ — with a headlamp. Click any component to see what it does, what correct looks like, and how it fails in the field. Then switch to INSPECT mode and hunt the hidden defects like a real inspector.

WASD crawl  ·  drag look  ·  click identify  ·  mobile: left pad moves, drag looks

What You’re Looking At — and Why Lenders Care

Every manufactured home on a pier-and-anchor system depends on one unbroken chain:

FOOTING PAD  →  BLOCK PIER  →  CAP & SHIMS  →  STEEL I-BEAM  →  TIE-DOWN STRAP  →  GROUND ANCHOR

Break any link and the home is compromised — usually invisibly, until wind or settlement finds it. A few things the trainer teaches that surprise most people:

  • Skirting is not a foundation. That brick or vinyl perimeter is cosmetic. The structure is the piers and straps behind it.
  • Diagonal straps only work side-to-side. The longitudinal ties at the end bays resist front-to-back movement — and they’re the single most commonly missing component in the field. Try INSPECT mode; almost everyone misses them the first time.
  • A single stack of blocks is only allowed to 36 inches. Taller piers need double-stacking or an engineer’s design (24 CFR 3285.303).
  • The stabilizer plate matters. Without it, the anchor shaft knifes sideways through the soil under load — the strap is tight right up until the moment it isn’t.

Buying, Selling, or Refinancing a Manufactured Home? You Probably Need This Letter.

FHA, VA, and most conventional lenders require a foundation certification from a licensed Professional Engineer stating the home meets HUD’s Permanent Foundations Guide. No letter, no closing — and it’s usually discovered a week before the closing date. We certify remotely from photos in most cases; the components you just explored are exactly what we evaluate.

  • Engineer-sealed certification letter accepted by FHA / VA / conventional lenders
  • Fast turnaround once evidence is complete — built for closing deadlines
  • If it doesn’t pass, you get an itemized repair scope instead of a vague rejection — fix it, send photos, we re-certify
GET MY CERTIFICATION LETTER → TALK TO AN ENGINEER

Licensed Professional Engineers · Multi-state · Evaluations per HUD PFGMH & 24 CFR Part 3285

Spotted One of These Under a Real Home?

If INSPECT mode looked familiar — a leaning pier, slack straps, missing longitudinal ties, blocks on bare dirt — that’s not a “watch it” item. It’s a load-path failure waiting on weather. We provide engineered repair scopes and re-certification: exactly what to fix, to what standard, with the sealed letter issued once corrected photos come back.

GET A REPAIR SCOPE + RE-CERT →
Buyers & Sellers

Closing on an FHA/VA loan? Get the required engineer’s certification before underwriting asks.

Order a cert →
Agents & Lenders

Pier-and-beam flagged on the appraisal? We turn certs fast and rescue closings. Volume partners welcome.

Partner with us →
Inspectors & Site Techs

Use this trainer with your team. Need a PE behind your field findings?

Work with us →
Built by Oasis Engineering — licensed Professional Engineers certifying manufactured home foundations nationwide.
The trainer is a teaching model (nominal dimensions) — for education, not construction.