Sarco DualGlaze Putty

Professional window restorers avoid hardware store glazing compounds not because they cost less, but because they fail within 5 to 10 years while properly applied linseed oil formulations routinely last 20 to 30 years.

What It Is

Sarco DualGlaze is a soybean and linseed oil-based glazing compound engineered for exterior window restoration where both wood and metal sash require bedding and face glazing. Unlike shop-only formulations that need controlled conditions, this compound benefits from outdoor atmospheric curing that produces stronger, more flexible bonds than fast-drying alternatives.

Why It Is Better

This remains the only glazing compound on the market that meets federal specification TT-P-781A, Type I and TT-G-00410E, the standards government agencies require for historic building restoration. The formulation maintains elasticity throughout its service life, allowing normal window movement without the cracking and pulling that plagues rigid compounds. While the 2 to 3 week skinning time feels slow compared to consumer products, this extended cure produces permanent watertight bonds that professional restorers trust for exterior applications where failure means water damage and expensive callbacks.

The Details

• Material Composition: Soybean and linseed oil base with mildew-resistant additives
• Coverage: One quart glazes approximately 84 linear feet of standard sash
• Substrate Compatibility: Adheres to wood, steel, and aluminum window frames for both bedding and face glazing
• Surface Preparation: Apply to primed glazing rabbets for optimal oil absorption control
• Skinning Time: Forms paintable surface in 2 to 3 weeks depending on temperature
• Working Temperature: Remains workable at 32°F and above, with optimal results from 60°F to 75°F

Applications

Designed specifically for on-site exterior glazing work where atmospheric conditions aid the curing process. Use for both bedding glass in glazing rabbets and face glazing over glazing points. The elastic formula accommodates thermal expansion in metal sash while remaining compatible with wood's moisture movement. Not recommended for interior shop applications where Type M formulations cure more predictably in controlled conditions.

Professional Usage

Government restoration projects specify Sarco compounds because decades of institutional experience prove their reliability on federally significant historic properties. Professional window restorers working on Victorian, Colonial, and Craftsman homes rely on the predictable working characteristics that allow proper tooling to smooth bevels before the compound begins setting. The slower cure time professionals initially question becomes the feature they value most once they understand that atmospheric oxidation produces stronger bonds than solvent evaporation.

When your restoration work needs to match the 80-year performance of original glazing, choose the compound that government agencies and master craftspeople have trusted for historic preservation work for decades.

Specifications

Frequently Asked Questions

Will this work with modern aluminum storm windows over historic wood sash?
Yes, DualGlaze adheres to aluminum, steel, and wood substrates. The elastic formulation accommodates the different thermal expansion rates between dissimilar materials without cracking or pulling loose.

How long does it last compared to hardware store glazing putty?
Properly applied DualGlaze typically performs for 20 to 30 years in exterior applications. Consumer-grade compounds often fail within 5 to 10 years due to rigid formulations that crack as windows expand and contract.

Can I paint over this immediately like traditional linseed oil putty?
No. While pure linseed oil putty accepts linseed oil paint immediately, DualGlaze requires 2 to 3 weeks to form a paintable skin. The extended cure produces superior weather resistance and longevity. Use oil-based primer for best adhesion when the surface skins sufficiently.

What makes this different from Sarco Type M compound?
Type M is formulated for interior shop applications on wood sash only, where controlled temperature and humidity allow faster, more predictable curing. DualGlaze is engineered for exterior on-site work in variable conditions and adheres to both wood and metal substrates.

How It Compares