Independent • Nationwide • 75+ Years

Honest, Expert Stained Glass Appraisal & Consulting

Protecting your stained glass investment with independent, unbiased appraisals and consulting. We work for you — not a studio. Serving churches, institutions, and collectors internationally.


75+
Years Combined Expertise
USPAP
Compliant Appraisals
Nationwide
Serving Organizations Across the Country
Inspecting stained glass windows in a restoration studio
Why Independent Consulting?

Your Windows Deserve an Unbiased Advocate


Many stained glass studios offer "free" inspections — then recommend their own restoration work. That's a conflict of interest, and it can cost you thousands.

NSGCG is different. We are not a studio. We don't sell glass or perform restoration work. Our only job is to give you honest answers and specifications that protect your investment.

  • Independent evaluations — no ties to any studio
  • Owner-representative approach — we work for you
  • Comprehensive documentation you can trust
  • Clear, plain-language recommendations
Our Promise

We Work for You — Not a Studio


When you hire NSGCG, you get an independent advocate. We don't sell glass, we don't perform restoration, and we don't earn commissions from vendors. Our only interest is giving you honest, expert guidance.

  • Unbiased recommendations — always
  • Owner-representative on every project
  • Clear specifications that protect your budget
  • Long-term preservation strategies
Karl Erickson and Cynthia Gallagher consulting at Reid Memorial Presbyterian Church
Common Questions

Frequently Asked Questions

Find answers to common questions about our stained glass consulting services.

Unlike studios, we don't have a vested interest in selling repairs. We provide unbiased evaluations, ensuring your needs—not a studio's sales agenda—dictate the specifications and decisions.

We oversee every step—from the initial RFP to the final installation. By aligning contractors with precise specifications, we prevent costly mistakes and ensure the project is done correctly, on budget, and on time.

With over 75 years of experience, we ensure your windows are properly valued, documented, and protected—whether for insurance claims, disaster planning, or future preservation.

Photographic documentation creates a permanent visual record. It aids in insurance claims, ensures restoration accuracy, and provides a benchmark for comparing the window's condition before and after intervention.

We provide apples-to-apples comparisons by ensuring every bid matches a consistent specification. This empowers you to choose based on quality and accuracy, not just price.

Client Testimonials

Trusted by Clients Nationwide

Hear from churches, collectors, and institutions who trust NSGCG for honest, expert stained glass guidance.

★★★★★

"Professional and accurate. I highly recommend them for your stained glass appraisals."

National Stained Glass Consulting did an excellent job with my appraisal. They were detail oriented with a quick turnaround time.

★★★★★

"Outstanding expertise — masterful analysis from just a few photos."

Karl gave me meticulous details about the glass, lead, and solder from my 1911 window — even a well-educated guess as to who made it. Quite prompt, with a very reasonable fee.

★★★★★

"His efforts far exceeded anyone else's — a truly non-biased professional assessment."

Karl took time to help me identify the origin and value of my stained glass pieces. I can tell when someone is genuinely looking out for my best interest. Very professional, very helpful.

Ready to Protect Your Stained Glass?

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