Licensed professional engineers · 38 states + USVI
Serious engineering. Remarkably simple.
Engineering letters, certifications, calculations and plans, with clear pricing and a straightforward process. Tell us what you’re working on, send your photos or documents, and we’ll help you figure out the next step. Most letters are delivered within 1–2 business days after we receive the required information. For projects that need a site visit, we can coordinate that too.
- 1–2 days
- Typical letter turnaround
- 38 states
- Firm licensure + USVI
- 5.0 ★
- 123 Google reviews
What we do
What can we help you with?
From a single engineer letter to a full home design: one front door for all of it.
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Engineer letter
Typically $295–$1,500, scoped per case · Typically 1–2 business days once we have what we need
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MH foundation certification
$450 flat · Typically 1–2 business days once we have what we need
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Plans review & certification
Typically $500–$700 for residential; commercial quoted · 2–3 business days from complete plans
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Container home
Custom quote · Scoped per project
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Wind calcs
Typically $1,000–$2,000 · 2–3 business days
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Energy calcs
$500 typical · 2–3 business days
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And much more
Design, calcs, field work and beyond.
EngineerLetters.co Modular / Boxabl Foundation Certification Letter
Sealed letter certifying the factory-built unit is installed on a permanent foundation per approved plans.
New Home Structural Design
Sealed structural drawings and calculations.
Remodel & Addition Engineering
Sealed drawings, beam/header sizing, or letters for remodels and additions.
Pergola, Pool & Patio Engineering
Sealed plans or letters for outdoor structures.
Engineering Consulting
Engineering opinion, review or report as scoped.
Soil Compaction Testing & PE Certification
Field density tests and sealed certification.
Tell us what you’re working on and we’ll point you to the right service.
Recent work
Built, sealed, standing.
Homes, backyards, landmarks and sculptures from Florida to Texas.
What others are saying
Rated 5.0 on Google.
Homeowners, realtors, lenders and contractors. Most of them came in through this same intake.
How it works
Bring what you’ve started. We’ll help you move it forward.
Sketches, plans, photos or an AI-assisted concept: show us what you’re working on. We’ll review what you have, explain what still needs engineering, and help you take the next step.
Step 1Show us what you have
Pick a service or just describe the project, and add whatever you have so far: plans, photos, permit records, DIY drawings or an AI-assisted concept. No starting point is too rough.
Step 2We review it with you
A licensed engineer looks at what you brought and explains what it can support, what still needs engineering, and whether the work can be done from records or needs a site visit. You see the price or a quote before work begins.
Step 3Engineered, sealed, delivered
We do the engineering the project needs, whether that’s calculations, design, inspection or a letter. A PE seals only the work they have reviewed and verified, and we deliver it by secure link.
Questions
Can an engineer letter replace a missed inspection?
Often, yes. When the work is still visible or was documented before it was covered, a licensed PE can review that evidence and issue a sealed letter many building departments accept in place of the missed inspection. Acceptance is always the jurisdiction's call, and concealed work with no documentation generally needs a site visit.
How fast is a manufactured home foundation certification?
Typically 1–2 business days after your photos, appraisal and documents are in. The service is $450 flat for FHA, VA, USDA and conventional closings. Some homes need an in-person visit. We tell you as soon as we have reviewed what you sent, and it is a 100% refund if we cannot help.
Do you work outside Florida?
Yes. Oasis Engineering holds firm licensure in 38 states plus the U.S. Virgin Islands. The intake checks your state before you spend any time.
From the founder
“I’m Enrique Lairet, a professional engineer and founder of Oasis Engineering. I like figuring out how to make unusual projects work, and making the engineering process easier to understand along the way.”
More about Oasis →Ready?
Two minutes to start. A real engineer reviews your project.
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