Business Details
45 Years
experience
Expert Window Sash Repair and Custom Manufacturing
Founded in 1981, Accurate Custom Sash & Mllwrk has established itself as a leader in custom window sash repair and manufacturing. As a family-run business, we prioritize personalized service, ensuring every client receives expert guidance to make informed decisions about their window and door needs. With over four decades of experience, our team combines advanced machinery with premium materials like 50-year rot-proof Accoya wood to deliver durable, precise repairs and custom solutions. We specialize in restoring historical wood windows, repairing casement and double-hung sashes, and sourcing obsolete hardware for brands like Rockwell and Biltbest. Our commitment to quality is reflected in our use of industrial-grade materials, stainless steel components, and meticulous craftsmanship.We offer same-day repairs by appointment, detailed installation instructions for DIYers, and nationwide shipping for parts. Our mission remains centered on exceptional customer service, avoiding pressure tactics while providing cost-effective alternatives to full window replacement. Testimonials highlight our ability to solve complex window challenges, from restoring energy efficiency to replicating historical designs. By maintaining a vast inventory of manufacturer samples, we ensure accurate duplication even when original brands are defunct. Our teams expertise extends to advising on material selection, performance enhancements, and preservation of architectural character, making us a trusted partner for homeowners and professionals alike.
Services
Window Sash Repair
Custom Sash Manufacturing
Historical Window Restoration
Hardware Replacement
Energy Efficiency Upgrades
Accoya Wood Installation
Same-Day Repairs
Nationwide Parts Shipping
DIY Installation Support
Obsolescent Hardware Sourcing
Details
- Year established: 1981
Highlights and features
- We offer 40+ years of specialized experience in wood window restoration.
- Our repairs use solid Accoya wood with a 50-year rot-proof warranty.
- We provide same-day sash repairs by appointment in our Oak Lawn shop.
- Our team duplicates sash profiles with industrial precision, not portable tools.
- We guarantee exact pattern matches using our inventory of original manufacturer samples.
What people say
Unmatched professionalism
Saved thousands replacing windows
Flawless millwork quality
Expert guidance
Perfect pattern matches
Services
Window Sash Repair
We repair rotting wood window sashes using solid Accoya wood with a 50-year warranty. Our process includes replacing damaged rails and stiles, installing stainless steel hardware, and applying premium silicone caulking. Repairs maintain original profiles while enhancing durability for long-term performance.
Custom Sash Manufacturing
We duplicate historical or obsolete sashes using computer-controlled machinery for exact pattern matching. Options include true divided light designs, insulated glass upgrades, and custom thicknesses from 1-3/8 to 2-1/4. All sashes use rot-resistant materials for exterior applications.
Hardware Replacement
We supply and install replacement hardware for brands like Rockwell, Biltbest, and Andersen. Products include casement operators, hinges, weather-stripping, and locks. Parts ship with installation instructions or receive same-day support at our Oak Lawn facility.
Historical Window Restoration
We restore putty-glazed historical sashes using Sarco-brand glazing compounds and clear northern white pine. Services include rope-and-weight double-hung windows, true divided light sashes, and energy-efficient Lo-E glass upgrades while preserving original architectural details.
Energy Efficiency Upgrades
We improve window performance through weather-stripping installation, insulated glass replacement, and Accoya wood upgrades. These modifications reduce energy costs by eliminating drafts while maintaining the aesthetic of original wood windows.
People
Mark Sirvin
Founder
Mark Sirvin founded Accurate Custom Sash & Mllwrk in 1981 with a focus on precision window restoration. He provides expert guidance on material selection and repair techniques, ensuring solutions that balance historical accuracy with modern durability for clients nationwide.
Pat Sirvin
Co-Owner
Pat Sirvin collaborates with clients to address window needs while maintaining the companys commitment to quality. With decades of experience, she ensures personalized service and attention to detail in every project undertaken by the family-run business.
Questions
Can you repair windows from discontinued brands?
Yes, we repair and duplicate sashes for obsolete brands like Rockwell and Biltbest using our inventory of original manufacturer samples.
Do you offer same-day repair services?
We provide same-day sash repairs at our Oak Lawn shop by appointment, typically taking 45 minutes per window.
What materials do you use for durability?
We use 50-year rot-proof Accoya wood and stainless steel hardware to ensure long-lasting window repairs resistant to weather damage.
Can you match historical window designs?
Yes, our computer-controlled machinery ensures exact profile matches for historical sashes, including true divided light and putty-glazed designs.
Do you ship parts nationwide?
We ship window repair parts and hardware nationwide with detailed installation instructions for DIYers.
How do you improve window energy efficiency?
We install PVC weather-stripping, insulated glass upgrades, and Lo-E coatings to enhance energy efficiency while preserving original window structures.
