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.
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
Comprehensive Stained Glass Expertise
From appraisals and inspections to restoration consulting and project management — everything you need to protect, preserve, and enhance your stained glass windows.
Stained Glass Appraisals
Professional valuations for insurance, estate, market, and replacement cost. Accurate, defensible documentation that protects your assets.
Get an AppraisalInspections & Condition Reports
Thorough structural and aesthetic evaluations with comprehensive documentation and preservation recommendations.
Learn MorePhotographic Documentation
High-resolution digital imaging and archival-quality records using reflected and transmitted light techniques.
Learn MoreHistorical Restoration
Expert guidance for historically accurate restoration. We write specifications and manage projects to preserve artistic integrity.
Learn MoreProtective Coverings
Independent specifications for protective glazing systems that safeguard your windows from environmental and accidental damage.
Learn MoreWe 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
- $1M general liability insurance coverage
Trusted by Clients Nationwide
Hear from churches, collectors, and institutions who trust NSGCG for honest, expert stained glass guidance.
National Stained Glass Consulting company did an excellent job with an appraisal for my stained glass. They were detail oriented and did a quick turn around time with sending me the appraisal. Professional and accurate. I highly recommend them to hire for your stained glass appraisals.
Outstanding expertise! The owner of NSGCG Karl Erickson was masterful in his analysis of just a few photos I sent to him. He gave me meticulous details about the glass, lead, and solder used in my stained glass window from 1911. He was even able to give me a very well educated guess as to who made it. Karl is quite prompt, with a very reasonable fee. I highly recommend his services.
I'd like to thank Karl at NSGCG for taking time from his busy day to help me identify the origin and determine the value of my stained glass pieces. His efforts far exceeded anyone else's that I had tried to contact concerning the matter. I can tell when someone is looking out for my best interest and giving me a non-biased professional assessment. Very professional, very helpful, and very much appreciated!